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Lloyd VJ, Burg SL, Harizanova J, Garcia E, Hill O, Enciso-Romero J, Cooper RL, Flenner S, Longo E, Greving I, Nadeau NJ, Parnell AJ. The actin cytoskeleton plays multiple roles in structural colour formation in butterfly wing scales. Nat Commun 2024; 15:4073. [PMID: 38769302 PMCID: PMC11106069 DOI: 10.1038/s41467-024-48060-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 04/19/2024] [Indexed: 05/22/2024] Open
Abstract
Vivid structural colours in butterflies are caused by photonic nanostructures scattering light. Structural colours evolved for numerous biological signalling functions and have important technological applications. Optically, such structures are well understood, however insight into their development in vivo remains scarce. We show that actin is intimately involved in structural colour formation in butterfly wing scales. Using comparisons between iridescent (structurally coloured) and non-iridescent scales in adult and developing H. sara, we show that iridescent scales have more densely packed actin bundles leading to an increased density of reflective ridges. Super-resolution microscopy across three distantly related butterfly species reveals that actin is repeatedly re-arranged during scale development and crucially when the optical nanostructures are forming. Furthermore, actin perturbation experiments at these later developmental stages resulted in near total loss of structural colour in H. sara. Overall, this shows that actin plays a vital and direct templating role during structural colour formation in butterfly scales, providing ridge patterning mechanisms that are likely universal across lepidoptera.
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Affiliation(s)
- Victoria J Lloyd
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK.
| | - Stephanie L Burg
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK
| | - Jana Harizanova
- Central Laser Facility-Science & Technology Facility Council, The Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0FA, UK
- Core Facility for Integrated Microscopy, Department of Biomedical Sciences, University of Copenhagen, 2200N, Copenhagen, Denmark
| | - Esther Garcia
- Central Laser Facility-Science & Technology Facility Council, The Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0FA, UK
| | - Olivia Hill
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK
| | - Juan Enciso-Romero
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK
- Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada
| | - Rory L Cooper
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK
- Department of Genetics and Evolution, University of Geneva, Sciences III, Geneva, 1205, Switzerland
| | - Silja Flenner
- Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, 21502, Geesthacht, Germany
| | - Elena Longo
- Elettra-Sincrotrone Trieste S.C.p.A., 34149, Basovizza, Trieste, Italy
| | - Imke Greving
- Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, 21502, Geesthacht, Germany
| | - Nicola J Nadeau
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK.
| | - Andrew J Parnell
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK.
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Zhang XM, Xu KL, Kong JH, Dong G, Dong SJ, Yang ZX, Xu SJ, Wang L, Luo SY, Zhang YD, Zhou CC, Gu WY, Mei SY. Heterozygous CAPZA2 mutations cause global developmental delay, hypotonia with epilepsy: a case report and the literature review. J Hum Genet 2024; 69:197-203. [PMID: 38374166 DOI: 10.1038/s10038-024-01230-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024]
Abstract
CAPZA2 encodes the α2 subunit of CAPZA, which is vital for actin polymerization and depolymerization in humans. However, understanding of diseases associated with CAPZA2 remains limited. To date, only three cases have been documented with neurodevelopmental abnormalities such as delayed motor development, speech delay, intellectual disability, hypotonia, and a history of seizures. In this study, we document a patient who exhibited seizures, mild intellectual disability, and impaired motor development yet did not demonstrate speech delay or hypotonia. The patient also suffered from recurrent instances of respiratory infections, gastrointestinal and allergic diseases. A novel de novo splicing variant c.219+1 G > A was detected in the CAPZA2 gene through whole-exome sequencing. This variant led to exon 4 skipping in mRNA splicing, confirmed by RT-PCR and Sanger sequencing. To our knowledge, this is the third study on human CAPZA2 defects, documenting the fourth unambiguously diagnosed case. Furthermore, this splicing mutation type is reported here for the first time. Our research offers additional support for the existence of a CAPZA2-related non-syndromic neurodevelopmental disorder. Our findings augment our understanding of the phenotypic range associated with CAPZA2 deficiency and enrich the knowledge of the mutational spectrum of the CAPZA2 gene.
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Affiliation(s)
- Xiao-Man Zhang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Kai-Li Xu
- Department of Pediatric Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Jing-Hui Kong
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Geng Dong
- Department of Clinical Laboratory, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Shi-Jie Dong
- Department of Radiology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Zhi-Xiao Yang
- Department of Pediatric Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Shu-Jing Xu
- Department of Pediatric Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Li Wang
- Department of Pediatric Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Shu-Ying Luo
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Yao-Dong Zhang
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Chong-Chen Zhou
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Wei-Yue Gu
- Chigene Translational Medical Research Center Co. Ltd, Beijing, China
| | - Shi-Yue Mei
- Henan Key Laboratory of Children's Genetics and Metabolic Diseases, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou, China.
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3
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Schöck F, González-Morales N. The insect perspective on Z-disc structure and biology. J Cell Sci 2022; 135:277280. [PMID: 36226637 DOI: 10.1242/jcs.260179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Myofibrils are the intracellular structures formed by actin and myosin filaments. They are paracrystalline contractile cables with unusually well-defined dimensions. The sliding of actin past myosin filaments powers contractions, and the entire system is held in place by a structure called the Z-disc, which anchors the actin filaments. Myosin filaments, in turn, are anchored to another structure called the M-line. Most of the complex architecture of myofibrils can be reduced to studying the Z-disc, and recently, important advances regarding the arrangement and function of Z-discs in insects have been published. On a very small scale, we have detailed protein structure information. At the medium scale, we have cryo-electron microscopy maps, super-resolution microscopy and protein-protein interaction networks, while at the functional scale, phenotypic data are available from precise genetic manipulations. All these data aim to answer how the Z-disc works and how it is assembled. Here, we summarize recent data from insects and explore how it fits into our view of the Z-disc, myofibrils and, ultimately, muscles.
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Affiliation(s)
- Frieder Schöck
- Department of Biology, McGill University, Montreal, Quebec, H3A 1B1, Canada
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Liu B, Ma X, Cai J. Construction and Analysis of Coexpression Network to Understand Biological Responses in Chickens Infected by Eimeria tenella. Front Vet Sci 2021; 8:688684. [PMID: 34307529 PMCID: PMC8299102 DOI: 10.3389/fvets.2021.688684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/11/2021] [Indexed: 12/15/2022] Open
Abstract
Coccidiosis, caused by various Eimeria species, is a major parasitic disease in chickens. Our understanding of how chickens respond to coccidian infections is highly limited at both the molecular and cellular levels. In this study, coexpression modules were identified by weighted gene coexpression network analysis in chickens infected with Eimeria tenella. A total of 15 correlation modules were identified using 5,175 genes with 24 chicken samples, 12 with primary and 12 with secondary E. tenella infection. The analysis of the interactions between these modules showed a high degree of scale independence. Gene Ontology and Kyoto Encyclopedia of Gene and Genomes enrichment analyses revealed that genes in these functional modules were involved in a broad categories of functions, such as immune response, amino acid metabolism, cellular responses to lipids, sterol biosynthetic processes, and RNA transport. Two modules viz yellow and magenta were identified significantly associating with infection status. Preservation analysis showed that most of the modules identified in E. tenella infections were highly or moderately preserved in chickens infected with either Eimeria acervulina or Eimeria maxima. These analyses outline a biological responses landscape for chickens infected by E. tenella, and also indicates that infections with these three Eimeria species elicit similar biological responses in chickens at the system level. These findings provide new clues and ideas for investigating the relationship between parasites and host, and the control of parasitic diseases.
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Affiliation(s)
- Baohong Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Xueting Ma
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Jianping Cai
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
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5
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Santio NM, Vainio V, Hoikkala T, Mung KL, Lång M, Vahakoski R, Zdrojewska J, Coffey ET, Kremneva E, Rainio EM, Koskinen PJ. PIM1 accelerates prostate cancer cell motility by phosphorylating actin capping proteins. Cell Commun Signal 2020; 18:121. [PMID: 32771000 PMCID: PMC7414696 DOI: 10.1186/s12964-020-00618-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/27/2020] [Indexed: 12/22/2022] Open
Abstract
Background The PIM family kinases promote cancer cell survival and motility as well as metastatic growth in various types of cancer. We have previously identified several PIM substrates, which support cancer cell migration and invasiveness. However, none of them are known to regulate cellular movements by directly interacting with the actin cytoskeleton. Here we have studied the phosphorylation-dependent effects of PIM1 on actin capping proteins, which bind as heterodimers to the fast-growing actin filament ends and stabilize them. Methods Based on a phosphoproteomics screen for novel PIM substrates, we have used kinase assays and fluorescence-based imaging techniques to validate actin capping proteins as PIM1 substrates and interaction partners. We have analysed the functional consequences of capping protein phosphorylation on cell migration and adhesion by using wound healing and real-time impedance-based assays. We have also investigated phosphorylation-dependent effects on actin polymerization by analysing the protective role of capping protein phosphomutants in actin disassembly assays. Results We have identified capping proteins CAPZA1 and CAPZB2 as PIM1 substrates, and shown that phosphorylation of either of them leads to increased adhesion and migration of human prostate cancer cells. Phosphorylation also reduces the ability of the capping proteins to protect polymerized actin from disassembly. Conclusions Our data suggest that PIM kinases are able to induce changes in actin dynamics to support cell adhesion and movement. Thus, we have identified a novel mechanism through which PIM kinases enhance motility and metastatic behaviour of cancer cells. Video abstract
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Affiliation(s)
- Niina M Santio
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Veera Vainio
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Tuuli Hoikkala
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Kwan Long Mung
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Mirka Lång
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Riitta Vahakoski
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Justyna Zdrojewska
- Turku Bioscience, University of Turku and Åbo Akademi University, 20520, Turku, Finland
| | - Eleanor T Coffey
- Turku Bioscience, University of Turku and Åbo Akademi University, 20520, Turku, Finland
| | - Elena Kremneva
- Institute of Biotechnology, University of Helsinki, 00014, Helsinki, Finland
| | - Eeva-Marja Rainio
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland
| | - Päivi J Koskinen
- Section of Physiology and Genetics, Department of Biology, University of Turku, Vesilinnantie 5, FI-20500, Turku, Finland.
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6
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Huang Y, Mao X, van Jaarsveld RH, Shu L, Terhal PA, Jia Z, Xi H, Peng Y, Yan H, Yuan S, Li Q, Wang H, Bellen HJ. Variants in CAPZA2, a member of an F-actin capping complex, cause intellectual disability and developmental delay. Hum Mol Genet 2020; 29:1537-1546. [PMID: 32338762 PMCID: PMC7268783 DOI: 10.1093/hmg/ddaa078] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/29/2020] [Accepted: 04/20/2020] [Indexed: 11/13/2022] Open
Abstract
The actin cytoskeleton is regulated by many proteins including capping proteins that stabilize actin filaments (F-actin) by inhibiting actin polymerization and depolymerization. Here, we report two pediatric probands who carry damaging heterozygous de novo mutations in CAPZA2 (HGNC: 1490) and exhibit neurological symptoms with shared phenotypes including global motor development delay, speech delay, intellectual disability, hypotonia and a history of seizures. CAPZA2 encodes a subunit of an F-actin-capping protein complex (CapZ). CapZ is an obligate heterodimer consisting of α and β heterodimer conserved from yeast to human. Vertebrate genomes contain three α subunits encoded by three different genes and CAPZA2 encodes the α2 subunit. The single orthologue of CAPZA genes in Drosophila is cpa. Loss of cpa leads to lethality in early development and expression of the human reference; CAPZA2 rescues this lethality. However, the two CAPZA2 variants identified in the probands rescue this lethality at lower efficiency than the reference. Moreover, expression of the CAPZA2 variants affects bristle morphogenesis, a process that requires extensive actin polymerization and bundling during development. Taken together, our findings suggest that variants in CAPZA2 lead to a non-syndromic neurodevelopmental disorder in children.
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Affiliation(s)
- Yan Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xiao Mao
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | | | - Li Shu
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Paulien A Terhal
- Department of Genetics, University Medical Center Utrecht, Utrecht CX 3584, The Netherlands
| | - Zhengjun Jia
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Hui Xi
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Ying Peng
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Huiming Yan
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Shan Yuan
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Qibin Li
- Clabee Genomics, Shenzhen, Guangdong 518000, China
- Center on Translational Neuroscience, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Hua Wang
- National Health Commission Key Laboratory of Birth Defects Research, Prevention and Treatment, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
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7
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Pharmaco-Genetic Screen To Uncover Actin Regulators Targeted by Prostaglandins During Drosophila Oogenesis. G3-GENES GENOMES GENETICS 2019; 9:3555-3565. [PMID: 31506320 PMCID: PMC6829128 DOI: 10.1534/g3.119.400704] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Prostaglandins (PGs) are lipid signaling molecules with numerous physiologic functions, including pain/inflammation, fertility, and cancer. PGs are produced downstream of cyclooxygenase (COX) enzymes, the targets of non-steroidal anti-inflammatory drugs (NSAIDs). In numerous systems, PGs regulate actin cytoskeletal remodeling, however, their mechanisms of action remain largely unknown. To address this deficiency, we undertook a pharmaco-genetic interaction screen during late-stage Drosophila oogenesis. Drosophila oogenesis is as an established model for studying both actin dynamics and PGs. Indeed, during Stage 10B, cage-like arrays of actin bundles surround each nurse cell nucleus, and during Stage 11, the cortical actin contracts, squeezing the cytoplasmic contents into the oocyte. Both of these cytoskeletal properties are required for follicle development and fertility, and are regulated by PGs. Here we describe a pharmaco-genetic interaction screen that takes advantage of the fact that Stage 10B follicles will mature in culture and COX inhibitors, such as aspirin, block this in vitro follicle maturation. In the screen, aspirin was used at a concentration that blocks 50% of the wild-type follicles from maturing in culture. By combining this aspirin treatment with heterozygosity for mutations in actin regulators, we quantitatively identified enhancers and suppressors of COX inhibition. Here we present the screen results and initial follow-up studies on three strong enhancers – Enabled, Capping protein, and non-muscle Myosin II Regulatory Light Chain. Overall, these studies provide new insight into how PGs regulate both actin bundle formation and cellular contraction, properties that are not only essential for development, but are misregulated in disease.
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Tsugawa H, Kato C, Mori H, Matsuzaki J, Kameyama K, Saya H, Hatakeyama M, Suematsu M, Suzuki H. Cancer Stem-Cell Marker CD44v9-Positive Cells Arise From Helicobacter pylori-Infected CAPZA1-Overexpressing Cells. Cell Mol Gastroenterol Hepatol 2019; 8:319-334. [PMID: 31146068 PMCID: PMC6713896 DOI: 10.1016/j.jcmgh.2019.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 05/15/2019] [Accepted: 05/21/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS CD44 variant 9 (CD44v9)-positive cancer stem-like cells strongly contribute to the development and recurrence of gastric cancer. However, the origin of CD44v9-positive cells is uncertain. METHODS CD44v9, β-catenin, and epithelial splicing regulatory protein 1 signals were assessed by real-time reverse-transcription polymerase chain reaction, immunoblot analysis, or immunofluorescence microscopy. Capping actin protein of muscle Z-line α subunit 1 (CAPZA1) expression was assessed by immunoblot analysis or immunohistochemical analysis of Mongolian gerbils' gastric mucosa or human biopsy specimens. Levels of oxidative stress were assessed by measuring malondialdehyde and protein carbonylation. Histone H3 acetylation levels in the CAPZA1 proximal promoter region were measured by using chromatin immunoprecipitation analysis with an antibody against the acetylated histone H3 in human gastric carcinoma cell line (AGS) cells. RESULTS CD44v9 is expressed in CAPZA1-overexpressing cells in human gastric cancer tissues. CAPZA1 overexpression enhanced expression of β-catenin, which is a transcription factor for CD44, and epithelial splicing regulatory protein 1, which increases alternative splicing of CD44 to generate CD44v9. CAPZA1-overexpressing cells after cytotoxin-associated gene A accumulation showed CD44v9 expression by inducing nuclear accumulation of β-catenin, concomitant with the enhancement of expression of Sal-like protein 4 and Krüppel-like factor 5, which encode reprogramming factors. Oxidative stress increased the CAPZA1 expression in AGS cells through the enhancement of histone H3 acetylation of CAPZA1 promoter. CAPZA1 expression was increased depending on oxidative stress in H pylori-infected gastric mucosa. CONCLUSIONS CD44v9 expression is evoked from CAPZA1-overexpressing cells after accumulation of cytotoxin-associated gene A. Our findings provide important insights into the mechanisms underlying the development of CD44v9-positive cells.
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Affiliation(s)
- Hitoshi Tsugawa
- Department of Biochemistry, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Chihiro Kato
- Medical Education Center, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Hideki Mori
- Division of Gastroenterology and Hepatology, National Hospital Organization Tokyo Medical Center, Meguro-ku, Tokyo, Japan
| | - Juntaro Matsuzaki
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
| | - Kaori Kameyama
- Department of Pathology, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Hideyuki Saya
- Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Masanori Hatakeyama
- Division of Microbiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Hidekazu Suzuki
- Department of Gastroenterology and Hepatology, Tokai University School of Medicine, Isehara, Kanagawa, Japan,Correspondence Address correspondence to: Hidekazu Suzuki, MD, PhD, FACG, AGAF, RFF, Department of Gastroenterology and Hepatology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. fax: +81(463)93-7134.
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9
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Tsugawa H, Mori H, Matsuzaki J, Sato A, Saito Y, Imoto M, Suematsu M, Suzuki H. CAPZA1 determines the risk of gastric carcinogenesis by inhibiting Helicobacter pylori CagA-degraded autophagy. Autophagy 2019; 15:242-258. [PMID: 30176157 PMCID: PMC6333452 DOI: 10.1080/15548627.2018.1515530] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 06/18/2018] [Accepted: 08/21/2018] [Indexed: 01/04/2023] Open
Abstract
Helicobacter pylori-derived CagA, a type IV secretion system effector, plays a role as an oncogenic driver in gastric epithelial cells. However, upon delivery into gastric epithelial cells, CagA is usually degraded by macroautophagy/autophagy. Hence, the induction of autophagy in H. pylori-infected epithelial cells is an important host-protective ability against gastric carcinogenesis. However, the mechanisms by which autophagosome-lysosome fusion is regulated, are unknown. Here, we report that enhancement of LAMP1 (lysosomal associated membrane protein 1) expression is necessary for autolysosome formation. LAMP1 expression is induced by nuclear translocated LRP1 (LDL receptor related protein 1) intracellular domain (LRP1-ICD) binding to the proximal LAMP1 promoter region. Nuclear translocation of LRP1-ICD is enhanced by H. pylori infection. In contrast, CAPZA1 (capping actin protein of muscle Z-line alpha subunit 1) inhibits LAMP1 expression via binding to LRP1-ICD in the nuclei. The binding of CAPZA1 to LRP1-ICD prevents LRP1-ICD binding to the LAMP1 proximal promoter. Thus, in CAPZA1-overexpressing gastric epithelial cells infected with H. pylori, autolysosome formation is inhibited and CagA escapes autophagic degradation. These findings identify CAPZA1 as a novel negative regulator of autolysosome formation and suggest that deregulation of CAPZA1 expression leads to increased risk of gastric carcinogenesis. Abbreviations: CagA: cytotoxin-associated gene A; CAPZA1: capping actin protein of muscle Z-line alpha subunit 1; ChIP: chromatin immunoprecipitation; GTF2I: general transcription factor IIi; HDAC: histone deacetylase; LAMP1: lysosomal associated membrane protein 1; LRP1: LDL receptor related protein 1; LRP1-ICD: CagA intracellular domain; qPCR: quantitative polymerase chain reaction; VacA: vacuolating cytotoxin.
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Affiliation(s)
- Hitoshi Tsugawa
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
| | - Hideki Mori
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Juntaro Matsuzaki
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, Tokyo, Japan
| | - Akira Sato
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan
| | - Yoshimasa Saito
- Division of Pharmacotherapeutics, Keio University Faculty of Pharmacy, Tokyo, Japan
| | - Masaya Imoto
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Kohoku-ku, Yokohama, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
| | - Hidekazu Suzuki
- Fellowship Training Center and Medical Education Center, Keio University School of Medicine, Tokyo, Japan
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10
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Xiong Z, Zhang H, Huang B, Liu Q, Wang Y, Shi D, Li X. Expression pattern of prohibitin, capping actin protein of muscle Z-line beta subunit and tektin-2 gene in Murrah buffalo sperm and its relationship with sperm motility. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2018; 31:1729-1737. [PMID: 29642674 PMCID: PMC6212766 DOI: 10.5713/ajas.18.0025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 03/19/2018] [Indexed: 01/13/2023]
Abstract
Objective The aim of the current study is to investigate the relationship between prohibitin (PHB), capping actin protein of muscle Z-line beta subunit (CAPZB), and tektin-2 (TEKT2) and sperm motility in Murrah buffalo. Methods We collected the high-motility and low-motility semen samples, testis, ovary, muscle, kidney, liver, brain and pituitary from Murrah buffalo, and analysed the expression of PHB, CAPZB, and TEKT2 in mRNA (message RNA) and protein level. Results Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) result showed that the expression of PHB was higher and CAPZB, TEKT2 were specifically expressed in testis as compared to the other 6 tissues, and that in testis, the expression of TEKT2 was higher than that of CAPZB and PHB. Immunohistochemistry test revealed that all three genes were located on the convoluted seminiferous tubule and enriched in spermatogenic cells. Both qRT-PCR and Western Blot results showed that the expression levels of PHB, CAPZB, and TEKT2 were significantly lower in the low-motility semen group compared to the high-motility semen group (p<0.05). Conclusion The expression levels of PHB, CAPZB, and TEKT2 in Murrah buffalo sperm have a high positive correlation with sperm motility. And the three genes may be potential molecular markers for the decline of buffalo sperm motility.
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Affiliation(s)
- Zhaocheng Xiong
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
| | - Haihang Zhang
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
| | - Ben Huang
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
| | - Qingyou Liu
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
| | - Yingqun Wang
- Guangxi Livestock and Poultry Variety Reforming Station, Nanning 530001, China
| | - Deshun Shi
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
| | - Xiangping Li
- State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
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11
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MoCAP proteins regulated by MoArk1-mediated phosphorylation coordinate endocytosis and actin dynamics to govern development and virulence of Magnaporthe oryzae. PLoS Genet 2017; 13:e1006814. [PMID: 28542408 PMCID: PMC5466339 DOI: 10.1371/journal.pgen.1006814] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 06/09/2017] [Accepted: 05/12/2017] [Indexed: 12/22/2022] Open
Abstract
Actin organization is a conserved cellular process that regulates the growth and development of eukaryotic cells. It also governs the virulence process of pathogenic fungi, such as the rice blast fungus Magnaporthe oryzae, with mechanisms not yet fully understood. In a previous study, we found that actin-regulating kinase MoArk1 displays conserved functions important in endocytosis and actin organization, and MoArk1 is required for maintaining the growth and full virulence of M. oryzae. To understand how MoArk1 might function, we identified capping protein homologs from M. oryzae (MoCAP) that interact with MoArk1 in vivo. MoCAP is heterodimer consisting of α and β subunits MoCapA and MoCapB. Single and double deletions of MoCAP subunits resulted in abnormal mycelial growth and conidia formation. The ΔMocap mutants also exhibited reduced appressorium penetration and invasive hyphal growth within host cells. Furthermore, the ΔMocap mutants exhibited delayed endocytosis and abnormal cytoskeleton assembly. Consistent with above findings, MoCAP proteins interacted with MoAct1, co-localized with actin during mycelial development, and participated in appressorial actin ring formation. Further analysis revealed that the S85 residue of MoCapA and the S285 residue of MoCapB were subject to phosphorylation by MoArk1 that negatively regulates MoCAP functions. Finally, the addition of exogenous phosphatidylinositol 4,5-bisphosphate (PIP2) failed to modulate actin ring formation in ΔMocap mutants, in contrast to the wild-type strain, suggesting that MoCAP may also mediate phospholipid signaling in the regulation of the actin organization. These results together demonstrate that MoCAP proteins whose functions are regulated by MoArk1 and PIP2 are important for endocytosis and actin dynamics that are directly linked to growth, conidiation and pathogenicity of M. oryzae. The actin-regulating kinase MoArk1 plays a conserved function in endocytosis and actin organization and is also essential for growth and full virulence of the rice blast fungus Magnaporthe oryzae. To understand how MoArk1 functions, we identified the F-actin capping protein α (MoCapA) and β (MoCapB) subunits that interact with MoArk1. We showed that single and double deletions of MoCAPA and MoCAPB result in slowed growth, reduced conidia production, abnormal morphogenesis, and attenuated virulence. We found that ΔMocap mutants are defective in endocytosis and actin organization and that MoCAP proteins are subject to regulation by MoArk1 through protein phosphorylation. Finally, we provided evidence demonstrating that MoCAP proteins modulate actin dynamics in response to phosphatidylinositol 4,5-biphosphate (PIP2). These combined results suggest that MoCAP proteins play an important role in endocytosis, actin organization, and virulence. Further studies of MoCAP proteins could lead to a better understanding of the connections between actin organization and host infection by M. oryzae.
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12
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Huang D, Cao L, Zheng S. CAPZA1 modulates EMT by regulating actin cytoskeleton remodelling in hepatocellular carcinoma. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:13. [PMID: 28093067 PMCID: PMC5240199 DOI: 10.1186/s13046-016-0474-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 12/12/2016] [Indexed: 12/20/2022]
Abstract
Background Epithelial-mesenchymal transition (EMT) elicits dramatic changes, including cytoskeleton remodelling as well as changes in gene expression and cellular phenotypes. During this process, actin filament assembly plays an important role in maintaining the morphology and movement of tumour cells. Capping protein, a protein complex referred to as CapZ, is an actin-binding complex that can regulate actin cytoskeleton remodelling. CAPZA1 is the α1 subunit of this complex, and we hypothesized that CAPZA1 regulates EMT through the regulation of actin filaments assembly, thus reducing the metastatic ability of hepatocellular carcinoma (HCC) cells. Methods Immunohistochemistry was used to detect CAPZA1 expression in 129 HCC tissues. Western blotting and qPCR were used to detect CAPZA1, EMT markers and EMT transcription factors in HCC cells. Transwell migration and invasion assays were performed to observe the migration and invasion of HCC cells. Cell Counting Kit-8 (CCK-8) was used to detect the proliferation of HCC cells. Immunoprecipitation was used to detect the interaction between CAPZA1 and actin filaments. Finally, a small animal magnetic resonance imager (MRI) was used to observe metastases in HCC cell xenografts in the liver. Results CAPZA1 expression levels were negatively correlated with the biological characteristics of primary HCC and patient prognosis. CAPZA1 expression was negatively correlated with the migration and invasion of HCC cells. CAPZA1 down regulation promoted the migration and invasion of HCC cells. Conversely, CAPZA1 overexpression significantly inhibited the migration and invasion of HCC cells. Moreover, CAPZA1 expression levels were correlated with the expression of the EMT markers E-cadherin, N-cadherin and Vimentin. Furthermore, the expression of Snail1 and ZEB1 were negatively correlated with CAPZA1 expression levels. Similarly, CAPZA1 significantly inhibited intrahepatic metastases of HCC cells in an orthotopic transplantation tumour model. Conclusions CAPZA1 inhibits EMT in HCC cells by regulating actin cytoskeleton remodelling, thereby reducing the metastatic ability of the cells. Together, our data suggest that CAPZA1 could be a useful biomarker for clinical determination of the prognosis of HCC patients.
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Affiliation(s)
- Deng Huang
- Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, No.29 Gaotanyan Road, Shapingba District, Chongqing, 400038, China
| | - Li Cao
- Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, No.29 Gaotanyan Road, Shapingba District, Chongqing, 400038, China
| | - Shuguo Zheng
- Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, No.29 Gaotanyan Road, Shapingba District, Chongqing, 400038, China.
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Otani T, Ogura Y, Misaki K, Maeda T, Kimpara A, Yonemura S, Hayashi S. IKKε inhibits PKC to promote Fascin-dependent actin bundling. Development 2016; 143:3806-3816. [PMID: 27578797 PMCID: PMC5087637 DOI: 10.1242/dev.138495] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 08/23/2016] [Indexed: 11/20/2022]
Abstract
Signaling molecules have pleiotropic functions and are activated by various extracellular stimuli. Protein kinase C (PKC) is activated by diverse receptors, and its dysregulation is associated with diseases including cancer. However, how the undesired activation of PKC is prevented during development remains poorly understood. We have previously shown that a protein kinase, IKKε, is active at the growing bristle tip and regulates actin bundle organization during Drosophila bristle morphogenesis. Here, we demonstrate that IKKε regulates the actin bundle localization of a dynamic actin cross-linker, Fascin. IKKε inhibits PKC, thereby protecting Fascin from inhibitory phosphorylation. Excess PKC activation is responsible for the actin bundle defects in IKKε-deficient bristles, whereas PKC is dispensable for bristle morphogenesis in wild-type bristles, indicating that PKC is repressed by IKKε in wild-type bristle cells. These results suggest that IKKε prevents excess activation of PKC during bristle morphogenesis. Summary: The protein kinase IKKϵ is active at the growing tip of Drosophila bristles and prevents excess PKC activation during bristle actin bundle organization and morphogenesis.
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Affiliation(s)
- Tetsuhisa Otani
- Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Yosuke Ogura
- Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Kazuyo Misaki
- Electron Microscope Laboratory, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Takuya Maeda
- Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Akiyo Kimpara
- Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Shigenobu Yonemura
- Electron Microscope Laboratory, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Shigeo Hayashi
- Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan .,Department of Biology, Kobe University Graduate School of Science, Kobe, Hyogo 657-8501, Japan
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14
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Ding X, Lu J, Yu R, Wang X, Wang T, Dong F, Peng B, Wu W, Liu H, Geng Y, Zhang R, Ma H, Cheng J, Yu M, Fang S. Preliminary Proteomic Analysis of A549 Cells Infected with Avian Influenza Virus H7N9 and Influenza A Virus H1N1. PLoS One 2016; 11:e0156017. [PMID: 27223893 PMCID: PMC4880285 DOI: 10.1371/journal.pone.0156017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 05/09/2016] [Indexed: 11/18/2022] Open
Abstract
A newly emerged H7N9 influenza virus poses high risk to human beings. However, the pathogenic mechanism of the virus remains unclear. The temporal response of primary human alveolar adenocarcinoma epithelial cells (A549) infected with H7N9 influenza virus and H1N1 influenza A virus (H1N1, pdm09) were evaluated using the proteomics approaches (2D-DIGE combined with MALDI-TOF-MS/MS) at 24, 48 and 72 hours post of the infection (hpi). There were 11, 12 and 33 proteins with significant different expressions (P<0.05) at 24, 48 and 72hpi, especially F-actin-capping protein subunit alpha-1 (CAPZA1), Ornithine aminotransferase (OAT), Poly(rC)-binding protein 1 (PCBP1), Eukaryotic translation initiation factor 5A-1 (EIF5A) and Platelet-activating factor acetylhydrolaseⅠb subunit beta (PAFAH1B2) were validated by western-blot analysis. The functional analysis revealed that the differential proteins in A549 cells involved in regulating cytopathic effect. Among them, the down-regulation of CAPZA1, OAT, PCBP1, EIF5A are related to the death of cells infected by H7N9 influenza virus. This is the first time show that the down-regulation of PAFAH1B2 is related to the later clinical symptoms of patients infected by H7N9 influenza virus. These findings may improve our understanding of pathogenic mechanism of H7N9 influenza virus in proteomics.
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Affiliation(s)
- Xiaoman Ding
- School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Jiahai Lu
- School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Ruoxi Yu
- Southern Medical University, Guangzhou, China
| | - Xin Wang
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Ting Wang
- Nanshan Center for Disease Control and Prevention, Shenzhen, China
| | - Fangyuan Dong
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Bo Peng
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Weihua Wu
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Hui Liu
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Yijie Geng
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Renli Zhang
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Hanwu Ma
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Jinquan Cheng
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Muhua Yu
- Nanshan Center for Disease Control and Prevention, Shenzhen, China
- * E-mail: (MHY); (SSF)
| | - Shisong Fang
- Major Infectious Disease Control Key Laboratory, Key Reference Laboratory of Pathogen and Biosafety, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
- * E-mail: (MHY); (SSF)
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15
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Mukaihara K, Suehara Y, Kohsaka S, Kubota D, Toda-Ishii M, Akaike K, Fujimura T, Kobayashi E, Yao T, Ladanyi M, Kaneko K, Saito T. Expression of F-actin-capping protein subunit beta, CAPZB, is associated with cell growth and motility in epithelioid sarcoma. BMC Cancer 2016; 16:206. [PMID: 26965049 PMCID: PMC4787035 DOI: 10.1186/s12885-016-2235-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 03/01/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A previous proteomics study demonstrated the overexpression of F-actin capping protein subunit beta (CAPZB) in tissue specimens of epithelioid sarcoma (EpiS). The aim of the present study was to elucidate the function of CAPZB in EpiS. METHODS Cellular functional assays were performed in two EpiS cell lines using CAPZB siRNAs. In addition, comparative protein expression analyses using Isobaric Tags for Relative and Absolute Quantitation (i-TRAQ) method were performed to identify the specific proteins whose expression was dysregulated by CAPZB, and analysed the data with the Ingenuity Pathways Analysis (IPA) system using the obtained protein profiles to clarify the functional pathway networks associated with the oncogenic function of CAPZB in EpiS. Additionally, we performed functional assays of the INI1 protein using INI1-overexpressing EpiS cells. RESULTS All 15 EpiS cases showed an immunohistochemical expression of CAPZB, and two EpiS cell lines exhibited a strong CAPZB expression. Silencing of CAPZB inhibited the growth, invasion and migration of the EpiS cells. Analysis of protein profiles using the IPA system suggested that SWI/SNF chromatin-remodeling complexes including INI1 may function as a possible upstream regulator of CAPZB. Furthermore, silencing of CAPZB resulted in a decreased expression of INI1 proteins in the INI1-positive EpiS cells, whereas the induction of INI1 in the INI1-deficient EpiS cells resulted in an increased CAPZB mRNA expression. CONCLUSIONS CAPZB is involved in tumor progression in cases of EpiS, irrespective of the INI1 expression, and may be a potential therapeutic target. The paradoxical relationship between the tumor suppressor INI1 and the oncoprotein CAPZB in the pathogenesis of EpiS remains to be clarified.
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Affiliation(s)
- Kenta Mukaihara
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Yoshiyuki Suehara
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan.
| | - Shinji Kohsaka
- Department of Medical Genomics Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Daisuke Kubota
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Midori Toda-Ishii
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Human Pathology, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Keisuke Akaike
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Human Pathology, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Tsutomu Fujimura
- Laboratory of Biochemical Analysis, Central Laboratory of Medical Sciences, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Eisuke Kobayashi
- Division of Musculoskeletal Oncology, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Takashi Yao
- Department of Human Pathology, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Marc Ladanyi
- Department of Pathology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Kazuo Kaneko
- Department of Orthopedic Surgery, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Tsuyoshi Saito
- Department of Human Pathology, School of Medicine, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, Japan
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16
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Mukherjee K, Ishii K, Pillalamarri V, Kammin T, Atkin JF, Hickey SE, Xi QJ, Zepeda CJ, Gusella JF, Talkowski ME, Morton CC, Maas RL, Liao EC. Actin capping protein CAPZB regulates cell morphology, differentiation, and neural crest migration in craniofacial morphogenesis†. Hum Mol Genet 2016; 25:1255-70. [PMID: 26758871 DOI: 10.1093/hmg/ddw006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 01/05/2016] [Indexed: 12/22/2022] Open
Abstract
CAPZB is an actin-capping protein that caps the growing end of F-actin and modulates the cytoskeleton and tethers actin filaments to the Z-line of the sarcomere in muscles. Whole-genome sequencing was performed on a subject with micrognathia, cleft palate and hypotonia that harbored a de novo, balanced chromosomal translocation that disrupts the CAPZB gene. The function of capzb was analyzed in the zebrafish model. capzb(-/-) mutants exhibit both craniofacial and muscle defects that recapitulate the phenotypes observed in the human subject. Loss of capzb affects cell morphology, differentiation and neural crest migration. Differentiation of both myogenic stem cells and neural crest cells requires capzb. During palate morphogenesis, defective cranial neural crest cell migration in capzb(-/-) mutants results in loss of the median cell population, creating a cleft phenotype. capzb is also required for trunk neural crest migration, as evident from melanophores disorganization in capzb(-/-) mutants. In addition, capzb over-expression results in embryonic lethality. Therefore, proper capzb dosage is important during embryogenesis, and regulates both cell behavior and tissue morphogenesis.
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Affiliation(s)
- Kusumika Mukherjee
- Center for Regenerative Medicine, Division of Plastic and Reconstructive Surgery, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Kana Ishii
- Center for Regenerative Medicine, Division of Plastic and Reconstructive Surgery, Department of Biochemistry and Molecular Biology, Nippon Medical School, Bunkyo, Tokyo 113-0022, Japan, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Vamsee Pillalamarri
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Tammy Kammin
- Department of Obstetrics, Gynecology and Reproductive Biology
| | - Joan F Atkin
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA, Division of Molecular and Human Genetics, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Scott E Hickey
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA, Division of Molecular and Human Genetics, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Qiongchao J Xi
- Department of Medicine, Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | | | - James F Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Michael E Talkowski
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA and Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Cynthia C Morton
- Department of Obstetrics, Gynecology and Reproductive Biology, Department of Pathology and Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA and Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Richard L Maas
- Department of Medicine, Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA, Harvard Medical School, Harvard University, Boston, MA 02114, USA
| | - Eric C Liao
- Center for Regenerative Medicine, Division of Plastic and Reconstructive Surgery, Harvard Medical School, Harvard University, Boston, MA 02114, USA
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Molecular Mechanism Underlying the Entomotoxic Effect of Colocasia esculenta Tuber Agglutinin against Dysdercus cingulatus. INSECTS 2015. [PMCID: PMC4693173 DOI: 10.3390/insects6040827] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Colocasia esculenta tuber agglutinin (CEA), a mannose binding lectin, exhibits insecticidal efficacy against different hemipteran pests. Dysdercus cingulatus, red cotton bug (RCB), has also shown significant susceptibility to CEA intoxication. However, the molecular basis behind such entomotoxicity of CEA has not been addressed adequately. The present study elucidates the mechanism of insecticidal efficacy of CEA against RCB. Confocal and scanning electron microscopic analyses documented CEA binding to insect midgut tissue, resulting in an alteration of perimicrovillar membrane (PMM) morphology. Internalization of CEA into insect haemolymph and ovary was documented by western blotting analyses. Ligand blot followed by mass spectrometric identification revealed the cognate binding partners of CEA as actin, ATPase and cytochrome P450. Deglycosylation and mannose inhibition assays indicated the interaction to probably be mannose mediated. Bioinformatic identification of putative glycosylation or mannosylation sites in the binding partners further supports the sugar mediated interaction. Correlating entomotoxicity of CEA with immune histological and binding assays to the insect gut contributes to a better understanding of the insecticidal potential of CEA and endorses its future biotechnological application.
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18
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Identification and characterization of a differentially expressed protein (CAPZB) in skeletal muscle between Meishan and Large White pigs. Gene 2014; 544:107-13. [PMID: 24792893 DOI: 10.1016/j.gene.2014.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 04/08/2014] [Accepted: 05/01/2014] [Indexed: 11/22/2022]
Abstract
Actin capping protein beta (CAPZB) protein was identified with considerable differences in the longissimus dorsi muscle between Large White and Meishan pigs using proteomics approach. However, in pigs, the information on CAPZB is very limited. In this study, we cloned and characterized the porcine actin capping protein beta (CAPZB) gene. In addition, we present two novel porcine CAPZB splice variants CAPZB1 and CAPZB2. CAPZB1 was expressed in all twenty tissues. However, CAPZB2 was predominantly expressed in the skeletal muscle and heart. In addition, the two isoforms had different expression profiles during the skeletal muscle development and between breeds. Moreover, the SNP T394G was identified in the coding region of the CAPZB gene, which was significantly associated with the carcass traits including the LFW, CFW, SFT and LEA. Data presented in our study suggests that the CAPZB gene may be a candidate gene of meat production trait and provides useful information for further studies on its roles in porcine skeletal muscle.
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Subunits of the Drosophila actin-capping protein heterodimer regulate each other at multiple levels. PLoS One 2014; 9:e96326. [PMID: 24788460 PMCID: PMC4008575 DOI: 10.1371/journal.pone.0096326] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 04/07/2014] [Indexed: 01/23/2023] Open
Abstract
The actin-Capping Protein heterodimer, composed of the α and β subunits, is a master F-actin regulator. In addition to its role in many cellular processes, Capping Protein acts as a main tumor suppressor module in Drosophila and in humans, in part, by restricting the activity of Yorkie/YAP/TAZ oncogenes. We aimed in this report to understand how both subunits regulate each other in vivo. We show that the levels and capping activities of both subunits must be tightly regulated to control F-actin levels and consequently growth of the Drosophila wing. Overexpressing capping protein α and β decreases both F-actin levels and tissue growth, while expressing forms of Capping Protein that have dominant negative effects on F-actin promote tissue growth. Both subunits regulate each other's protein levels. In addition, overexpressing one of the subunit in tissues knocked-down for the other increases the mRNA and protein levels of the subunit knocked-down and compensates for its loss. We propose that the ability of the α and β subunits to control each other's levels assures that a pool of functional heterodimer is produced in sufficient quantities to restrict the development of tumor but not in excess to sustain normal tissue growth.
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Li J, Staiger BH, Henty-Ridilla JL, Abu-Abied M, Sadot E, Blanchoin L, Staiger CJ. The availability of filament ends modulates actin stochastic dynamics in live plant cells. Mol Biol Cell 2014; 25:1263-75. [PMID: 24523291 PMCID: PMC3982992 DOI: 10.1091/mbc.e13-07-0378] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A network of individual filaments that undergoes incessant remodeling through a process known as stochastic dynamics comprises the cortical actin cytoskeleton in plant epidermal cells. From images at high spatial and temporal resolution, it has been inferred that the regulation of filament barbed ends plays a central role in choreographing actin organization and turnover. How this occurs at a molecular level, whether different populations of ends exist in the array, and how individual filament behavior correlates with the overall architecture of the array are unknown. Here we develop an experimental system to modulate the levels of heterodimeric capping protein (CP) and examine the consequences for actin dynamics, architecture, and cell expansion. Significantly, we find that all phenotypes are the opposite for CP-overexpression (OX) cells compared with a previously characterized cp-knockdown line. Specifically, CP OX lines have fewer filament-filament annealing events, as well as reduced filament lengths and lifetimes. Further, cp-knockdown and OX lines demonstrate the existence of a subpopulation of filament ends sensitive to CP concentration. Finally, CP levels correlate with the biological process of axial cell expansion; for example, epidermal cells from hypocotyls with reduced CP are longer than wild-type cells, whereas CP OX lines have shorter cells. On the basis of these and other genetic studies in this model system, we hypothesize that filament length and lifetime positively correlate with the extent of axial cell expansion in dark-grown hypocotyls.
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Affiliation(s)
- Jiejie Li
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-2064 Institute of Plant Sciences, Volcani Center, Bet-Dagan 50250, Israel Institut de Recherches en Technologie et Sciences pour le Vivant, Laboratoire de Physiologie Cellulaire et Végétale, Comissariat a l'Energie Atomique/Centre National de la Recherche Scientifique/Institute de la Recherche Agronomique/Université Joseph Fourier, F38054 Grenoble, France Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907
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Ogienko AA, Karagodin DA, Lashina VV, Baiborodin SI, Omelina ES, Baricheva EM. Capping protein beta is required for actin cytoskeleton organisation and cell migration during Drosophila oogenesis. Cell Biol Int 2014; 37:149-59. [PMID: 23339103 DOI: 10.1002/cbin.10025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 11/24/2012] [Indexed: 11/08/2022]
Abstract
Capping protein (CP) is a well-characterised actin-binding protein important for regulation of actin filament (AF) assembly. CP caps the barbed end of AFs, inhibiting the addition and loss of actin monomers. In Drosophila melanogaster, the gene encoding CP β-subunit is named capping protein beta (cpb; see Hopmann et al. [1996] J Cell Biol 133: 1293-305). The cpb level is reduced in the Drosophila bristle actin cytoskeleton and becomes disorganised with abnormal morphology. A reduced level of the CP protein in ovary results in disruption of oocyte determination, and disturbance of nurse cell (NC) cortical integrity and dumping. We describe novel defects appearing in cpb mutants during oogenesis, in which cpb plays an important role in border and centripetal follicle cell migration, ring canal development and cytoplasmic AF formation. The number of long cytoplasmic AFs was dramatically reduced in cpb hypomorphs and abnormal actin aggregates was seen on the inner side of NC membranes. A hypothesis to explain the formation of abnormal short-cut cytoplasmic AFs and actin aggregates in the cpb mutant NCs was proffered, along with a discussion of the reasons for 'dumpless' phenotype formation in the mutants.
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Affiliation(s)
- Anna A Ogienko
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, pr. Lavrentieva 10, Novosibirsk 630090, Russia.
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Lee YJ, Jeong SH, Hong SC, Cho BI, Ha WS, Park ST, Choi SK, Jung EJ, Ju YT, Jeong CY, Kim JW, Lee CW, Yoo J, Ko GH. Prognostic value of CAPZA1 overexpression in gastric cancer. Int J Oncol 2013; 42:1569-77. [PMID: 23545944 PMCID: PMC3661194 DOI: 10.3892/ijo.2013.1867] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/04/2013] [Indexed: 11/06/2022] Open
Abstract
F-actin capping protein α1 subunit (CAPZA1) was previously identified in a proteomic analysis of human gastric cancer clinical specimens and selected for further study. The association between CAPZA1 overexpression, detected by immunohistochemistry, and clinicopathological features including survival were evaluated. In vitro gain-of-function and loss-of-function approaches were utilized to assess the function of CPAZA1 in malignancy. Univariate analysis revealed that poorly differentiated disease, according to the World Health Organization (WHO) classification, advanced T stage, positive lymph nodes, high TNM stage, D2 lymph node dissection, adjuvant chemotherapy and CAPZA1 underexpression were significantly associated with cancer-related death (p<0.05); however, only high TNM stage remained significantly associated by multivariate analysis (p<0.01). CAPZA1 overexpression was associated with well differentiated histology, smaller tumor size, lower T stage, absence of lymph node metastasis, lower TNM stage, lower recurrence rate and longer survival time, compared to CAPZA1 underexpression. In vitro, forced expression of CAPZA1 caused a significant decrease in gastric cancer cell migration and invasion, whereas CAPZA1 depletion had the opposite effect. The present study suggests that CAPZA1 could be a marker of good prognosis in gastric cancer and shows that CAPZA1 is associated with decreased cancer cell migration and invasion.
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Affiliation(s)
- Young-Joon Lee
- Department of Surgery, Postgraduate School of Medicine, Gyeongnam Regional Cancer Center, Gyeongsang National University, Jinju, Republic of Korea
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Bao Y, Kake T, Hanashima A, Nomiya Y, Kubokawa K, Kimura S. Actin capping proteins, CapZ (β-actinin) and tropomodulin in amphioxus striated muscle. Gene 2012; 510:78-86. [DOI: 10.1016/j.gene.2012.07.081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/24/2012] [Accepted: 07/31/2012] [Indexed: 01/08/2023]
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Li J, Henty-Ridilla JL, Huang S, Wang X, Blanchoin L, Staiger CJ. Capping protein modulates the dynamic behavior of actin filaments in response to phosphatidic acid in Arabidopsis. THE PLANT CELL 2012; 24:3742-54. [PMID: 22960908 PMCID: PMC3480299 DOI: 10.1105/tpc.112.103945] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 08/07/2012] [Accepted: 08/16/2012] [Indexed: 05/19/2023]
Abstract
Remodeling of actin filament arrays in response to biotic and abiotic stimuli is thought to require precise control over the generation and availability of filament ends. Heterodimeric capping protein (CP) is an abundant filament capper, and its activity is inhibited by membrane signaling phospholipids in vitro. How exactly CP modulates the properties of filament ends in cells and whether its activity is coordinated by phospholipids in vivo is not well understood. By observing directly the dynamic behavior of individual filament ends in the cortical array of living Arabidopsis thaliana epidermal cells, we dissected the contribution of CP to actin organization and dynamics in response to the signaling phospholipid, phosphatidic acid (PA). Here, we examined three cp knockdown mutants and found that reduced CP levels resulted in more dynamic activity at filament ends, and this significantly enhanced filament-filament annealing and filament elongation from free ends. The cp mutants also exhibited more dense actin filament arrays. Treatment of wild-type cells with exogenous PA phenocopied the actin-based defects in cp mutants, with an increase in the density of filament arrays and enhanced annealing frequency. These cytoskeletal responses to exogenous PA were completely abrogated in cp mutants. Our data provide compelling genetic evidence that the end-capping activity of CP is inhibited by membrane signaling lipids in eukaryotic cells. Specifically, CP acts as a PA biosensor and key transducer of fluxes in membrane signaling phospholipids into changes in actin cytoskeleton dynamics.
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Affiliation(s)
- Jiejie Li
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2064
| | | | - Shanjin Huang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2064
| | - Xia Wang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2064
| | - Laurent Blanchoin
- Institut de Recherches en Technologie et Sciences pour le Vivant, Laboratoire de Physiologie Cellulaire and Végétale, Commissariat á l’Energie Atomique/Centre National de la Recherche Scientifique/Institut National de la Recherche Agronomique/Université Joseph Fourier, F38054 Grenoble, France
| | - Christopher J. Staiger
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2064
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana 47907
- Address correspondence to
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Wang J, Qian D, Fan T, Jia H, An L, Xiang Y. Arabidopsis actin capping protein (AtCP) subunits have different expression patterns, and downregulation of AtCPB confers increased thermotolerance of Arabidopsis after heat shock stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 193-194:110-119. [PMID: 22794924 DOI: 10.1016/j.plantsci.2012.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/30/2012] [Accepted: 06/04/2012] [Indexed: 05/16/2023]
Abstract
As a heterodimer actin-binding protein, capping protein is composed of α and β subunits, and can stabilize the actin filament cytoskeleton by binding to F-actin ends to inhibit G-actin addition or loss from that end. Until now, studies on plant capping protein have focused on biochemical functions in vitro, and so the expression patterns and physiological functions of actin capping protein in Arabidopsis (AtCP) are poorly understood. In the present study, real-time quantitative PCR and Western blot analysis showed that although AtCP α and β subunits (i.e. AtCPA and AtCPB) were expressed in various tissues, their expression patterns were significantly different. GUS staining further indicated they were present in different parts of the same organs. We also demonstrated that the expression levels of both subunits were induced by heat shock stress. However, only the atcpβ-mutant showed enhanced thermotolerance, and confocal microscopy showed that the actin filaments of the atcpβ-mutant were much more complete than that in the wild-type and the atcpα-mutant after heat treatment at 45 °C for 40 and 45 min. In conclusion, these results demonstrated that AtCPA and AtCPB showed distinct expression patterns in vivo, and that downregulation of AtCPB conferred increased plant thermotolerance after heat shock stress.
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Affiliation(s)
- Jue Wang
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Dong Qian
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tingting Fan
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Honglei Jia
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Lizhe An
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Yun Xiang
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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Woltedji D, Song F, Zhang L, Gala A, Han B, Feng M, Fang Y, Li J. Western Honeybee Drones and Workers (Apis mellifera ligustica) Have Different Olfactory Mechanisms than Eastern Honeybees (Apis cerana cerana). J Proteome Res 2012; 11:4526-40. [DOI: 10.1021/pr300298w] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dereje Woltedji
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Feifei Song
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Lan Zhang
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Alemayehu Gala
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Bin Han
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Mao Feng
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Yu Fang
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
| | - Jianke Li
- Institute
of Apicultural Research/Key Laboratory of
Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science, Beijing, China
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The interaction of capping protein with the barbed end of the actin filament. J Mol Biol 2010; 404:794-802. [PMID: 20969875 DOI: 10.1016/j.jmb.2010.10.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/11/2010] [Accepted: 10/12/2010] [Indexed: 11/21/2022]
Abstract
The interaction of capping protein (CP) with actin filaments is an essential element of actin assembly and actin-based motility in nearly all eukaryotes. The dendritic nucleation model for Arp2/3-based lamellipodial assembly features capping of barbed ends by CP, and the formation of filopodia is proposed to involve inhibition of capping by formins and other proteins. To understand the molecular basis for how CP binds the barbed end of the actin filament, we have used a combination of computational and experimental approaches, primarily involving molecular docking and site-directed mutagenesis. We arrive at a model that supports all of our biochemical data and agrees very well with a cryo-electron microscopy structure of the capped filament. CP interacts with both actin protomers at the barbed end of the filament, and the amphipathic helix at the C-terminus of the β-subunit binds to the hydrophobic cleft on actin, in a manner similar to that of WH2 domains. These studies provide us with new molecular insight into how CP binds to the actin filament.
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Hishiya A, Kitazawa T, Takayama S. BAG3 and Hsc70 interact with actin capping protein CapZ to maintain myofibrillar integrity under mechanical stress. Circ Res 2010; 107:1220-31. [PMID: 20884878 DOI: 10.1161/circresaha.110.225649] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
RATIONALE A homozygous disruption or genetic mutation of the bag3 gene, a member of the Bcl-2-associated athanogene (BAG) family proteins, causes cardiomyopathy and myofibrillar myopathy that is characterized by myofibril and Z-disc disruption. However, the detailed disease mechanism is not yet fully understood. OBJECTIVE bag3(-/-) mice exhibit differences in the extent of muscle degeneration between muscle groups with muscles experiencing the most usage degenerating at an accelerated rate. Usage-dependent muscle degeneration suggests a role for BAG3 in supporting cytoskeletal connections between the Z-disc and myofibrils under mechanical stress. The mechanism by which myofibrillar structure is maintained under mechanical stress remains unclear. The purpose of the study is to clarify the detailed molecular mechanism of BAG3-mediated muscle maintenance under mechanical stress. METHODS AND RESULTS To address the question of whether bag3 gene knockdown induces myofibrillar disorganization caused by mechanical stress, in vitro mechanical stretch experiments using rat neonatal cardiomyocytes and a short hairpin RNA-mediated gene knockdown system of the bag3 gene were performed. As expected, mechanical stretch rapidly disrupts myofibril structures in bag3 knockdown cardiomyocytes. BAG3 regulates the structural stability of F-actin through the actin capping protein, CapZβ1, by promoting association between Hsc70 and CapZβ1. BAG3 facilitates the distribution of CapZβ1 to the proper location, and dysfunction of BAG3 induces CapZ ubiquitin-proteasome-mediated degradation. Inhibition of CapZβ1 function by overexpressing CapZβ2 increased myofibril vulnerability and fragmentation under mechanical stress. On the other hand, overexpression of CapZβ1 inhibits myofibrillar disruption in bag3 knockdown cells under mechanical stress. As a result, heart muscle isolated from bag3(-/-) mice exhibited myofibrillar degeneration and lost contractile activity after caffeine contraction. CONCLUSIONS These results suggest novel roles for BAG3 and Hsc70 in stabilizing myofibril structure and inhibiting myofibrillar degeneration in response to mechanical stress. These proteins are possible targets for further research to identify therapies for myofibrillar myopathy or other degenerative diseases.
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Affiliation(s)
- Akinori Hishiya
- Boston Biomedical Research Institute, Watertown, MA 02472, USA
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Abstract
Investigations into the possible roles of human HSPB1 in aging have focused on its role as a molecular chaperone protecting partially folded or unfolded proteins, particularly during oxidative stress. A thorough analysis of potential roles of HSPB1 in aging cells has been hampered by a limited knowledge of its functions in living cells. Most studies have employed cell-free extracts and purified proteins. For example, HSPB1 is known to bind actin in vitro, and this observation led to the hypothesis that HSPB1 regulates actin filament dynamics. In the study summarized herein, the role of HSPB1 in regulating actin filament dynamics was further investigated by using cultured human cells. These results show that HSPB1 and actin form a complex in vivo and that HSPB1 is important for cell motility. A model for HSPB1 as a regulator of actin filament dynamics is presented, and evidence from the literature on cytoskeletal alterations in aging cells is discussed.
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Affiliation(s)
- Bindi M Doshi
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
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Doshi BM, Hightower LE, Lee J. The role of Hsp27 and actin in the regulation of movement in human cancer cells responding to heat shock. Cell Stress Chaperones 2009; 14:445-57. [PMID: 19224398 PMCID: PMC2728279 DOI: 10.1007/s12192-008-0098-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 12/12/2008] [Accepted: 12/30/2008] [Indexed: 11/29/2022] Open
Abstract
Human heat shock 27-kDa protein 1 (HSPB1)/heat shock protein (Hsp) 27 is a small heat shock protein which is thought to have several roles within the cell. One of these roles includes regulating actin filament dynamics in cell movement, since Hsp27 has previously been found to inhibit actin polymerization in vitro. In this study, the role of Hsp27 in regulating actin filament dynamics is further investigated. Hsp27 protein levels were reduced using siRNA in SW480 cells, a human colon cancer cell line. An in vitro wound closure assay showed that cells with knocked down Hsp27 levels were unable to close wounds, indicating that this protein is involved in regulating cell motility. Immunoprecipitation pull down assays were done, to observe if and when Hsp27 and actin are in the same complex within the cell, before and after heat shock. At all time points tested, Hsp27 and actin were present in the same cell lysate fraction. Lastly, indirect immunostaining was done before and after heat shock to evaluate Hsp27 and actin interaction in cells. Hsp27 and actin showed colocalization before heat shock, little association 3 h after heat shock, and increased association 24 h after heat shock. Cytoprotection was observed as early as 3 h after heat shock, yet cells were still able to move. These results show that Hsp27 and actin are in the same complex in cells and that Hsp27 is important for cell motility.
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Affiliation(s)
| | | | - Juliet Lee
- University of Connecticut, Storrs, CT USA
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Ganter M, Schüler H, Matuschewski K. Vital role for the Plasmodium actin capping protein (CP) beta-subunit in motility of malaria sporozoites. Mol Microbiol 2009; 74:1356-67. [PMID: 19682250 PMCID: PMC2810434 DOI: 10.1111/j.1365-2958.2009.06828.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Successful malaria transmission from the mosquito vector to the mammalian host depends crucially on active sporozoite motility. Sporozoite locomotion and host cell invasion are driven by the parasite's own actin/myosin motor. A unique feature of this motor machinery is the presence of very short subpellicular actin filaments. Therefore, F-actin stabilizing proteins likely play a central role in parasite locomotion. Here, we investigated the role of the Plasmodium berghei actin capping protein (PbCP), an orthologue of the heterodimeric regulator of filament barbed end growth, by reverse genetics. Parasites containing a deletion of the CP beta-subunit developed normally during the pathogenic erythrocytic cycle. However, due to reduced ookinete motility, mutant parasites form fewer oocysts and sporozoites in the Anopheles vector. These sporozoites display a vital deficiency in forward gliding motility and fail to colonize the mosquito salivary glands, resulting in complete attenuation of life cycle progression. Together, our results show that the CP beta-subunit exerts an essential role in the insect vector before malaria transmission to the mammalian host. The vital role is restricted to fast locomotion, as displayed by Plasmodium sporozoites.
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Affiliation(s)
- Markus Ganter
- Department of Parasitology, Heidelberg University School of Medicine, 69120 Heidelberg, Germany
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Chen N, Qu X, Wu Y, Huang S. Regulation of actin dynamics in pollen tubes: control of actin polymer level. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2009; 51:740-750. [PMID: 19686371 DOI: 10.1111/j.1744-7909.2009.00850.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Actin cytoskeleton undergoes rapid reorganization in response to internal and external cues. How the dynamics of actin cytoskeleton are regulated, and how its dynamics relate to its function are fundamental questions in plant cell biology. The pollen tube is a well characterized actin-based cell morphogenesis in plants. One of the striking features of actin cytoskeleton characterized in the pollen tube is its surprisingly low level of actin polymer. This special phenomenon might relate to the function of actin cytoskeleton in pollen tubes. Understanding the molecular mechanism underlying this special phenomenon requires careful analysis of actin-binding proteins that modulate actin dynamics directly. Recent biochemical and biophysical analyses of several highly conserved plant actin-binding proteins reveal unusual and unexpected properties, which emphasizes the importance of carefully analyzing their action mechanism and cellular activity. In this review, we highlight an actin monomer sequestering protein, a barbed end capping protein and an F-actin severing and dynamizing protein in plant. We propose that these proteins function in harmony to regulate actin dynamics and maintain the low level of actin polymer in pollen tubes.
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Affiliation(s)
- Naizhi Chen
- Center for Signal Transduction and Metabolomics, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
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Surviving the cold: molecular analyses of insect cryoprotective dehydration in the Arctic springtail Megaphorura arctica (Tullberg). BMC Genomics 2009; 10:328. [PMID: 19622137 PMCID: PMC2726227 DOI: 10.1186/1471-2164-10-328] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 07/21/2009] [Indexed: 01/24/2023] Open
Abstract
Background Insects provide tractable models for enhancing our understanding of the physiological and cellular processes that enable survival at extreme low temperatures. They possess three main strategies to survive the cold: freeze tolerance, freeze avoidance or cryoprotective dehydration, of which the latter method is exploited by our model species, the Arctic springtail Megaphorura arctica, formerly Onychiurus arcticus (Tullberg 1876). The physiological mechanisms underlying cryoprotective dehydration have been well characterised in M. arctica and to date this process has been described in only a few other species: the Antarctic nematode Panagrolaimus davidi, an enchytraied worm, the larvae of the Antarctic midge Belgica antarctica and the cocoons of the earthworm Dendrobaena octaedra. There are no in-depth molecular studies on the underlying cold survival mechanisms in any species. Results A cDNA microarray was generated using 6,912 M. arctica clones printed in duplicate. Analysis of clones up-regulated during dehydration procedures (using both cold- and salt-induced dehydration) has identified a number of significant cellular processes, namely the production and mobilisation of trehalose, protection of cellular systems via small heat shock proteins and tissue/cellular remodelling during the dehydration process. Energy production, initiation of protein translation and cell division, plus potential tissue repair processes dominate genes identified during recovery. Heat map analysis identified a duplication of the trehalose-6-phosphate synthase (TPS) gene in M. arctica and also 53 clones co-regulated with TPS, including a number of membrane associated and cell signalling proteins. Q-PCR on selected candidate genes has also contributed to our understanding with glutathione-S-transferase identified as the major antioxdidant enzyme protecting the cells during these stressful procedures, and a number of protein kinase signalling molecules involved in recovery. Conclusion Microarray analysis has proved to be a powerful technique for understanding the processes and genes involved in cryoprotective dehydration, beyond the few candidate genes identified in the current literature. Dehydration is associated with the mobilisation of trehalose, cell protection and tissue remodelling. Energy production, leading to protein production, and cell division characterise the recovery process. Novel membrane proteins, along with aquaporins and desaturases, have been identified as promising candidates for future functional analyses to better understand membrane remodelling during cellular dehydration.
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Gates J, Nowotarski SH, Yin H, Mahaffey JP, Bridges T, Herrera C, Homem CCF, Janody F, Montell DJ, Peifer M. Enabled and Capping protein play important roles in shaping cell behavior during Drosophila oogenesis. Dev Biol 2009; 333:90-107. [PMID: 19576200 DOI: 10.1016/j.ydbio.2009.06.030] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Revised: 06/20/2009] [Accepted: 06/22/2009] [Indexed: 12/29/2022]
Abstract
During development, cells craft an impressive array of actin-based structures, mediating events as diverse as cytokinesis, apical constriction, and cell migration. One challenge is to determine how cells regulate actin assembly and disassembly to carry out these cell behaviors. During Drosophila oogenesis diverse cell behaviors are seen in the soma and germline. We used oogenesis to explore developmental roles of two important actin regulators: Enabled/VASP proteins and Capping protein. We found that Enabled plays an important role in cortical integrity of nurse cells, formation of robust bundled actin filaments in late nurse cells that facilitate nurse cell dumping, and migration of somatic border cells. During nurse cell dumping, Enabled localizes to barbed ends of the nurse cell actin filaments, suggesting its mechanism of action. We further pursued this mechanism using mutant Enabled proteins, each affecting one of its protein domains. These data suggest critical roles for the EVH2 domain and its tetramerization subdomain, while the EVH1 domain appears less critical. Enabled appears to be negatively regulated during oogenesis by Abelson kinase. We also explored the function of Capping protein. This revealed important roles in oocyte determination, nurse cell cortical integrity and nurse cell dumping, and support the idea that Capping protein and Enabled act antagonistically during dumping. Together these data reveal places that these actin regulators shape oogenesis.
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Affiliation(s)
- Julie Gates
- Lineberger Comprehensive Cancer Center and Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Purification of capping protein using the capping protein binding site of CARMIL as an affinity matrix. Protein Expr Purif 2009; 67:113-9. [PMID: 19427903 DOI: 10.1016/j.pep.2009.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 04/29/2009] [Accepted: 05/01/2009] [Indexed: 11/23/2022]
Abstract
Capping protein (CP) is a ubiquitously expressed, heterodimeric actin binding protein that is essential for normal actin dynamics in cells. The existing methods for purifying native CP from tissues and recombinant CP from bacteria are time-consuming processes that involve numerous conventional chromatographic steps and functional assays to achieve a homogeneous preparation of the protein. Here, we report the rapid purification of Acanthamoeba CP from amoeba extracts and recombinant mouse CP from E. coli extracts using as an affinity matrix GST-fusion proteins containing the CP binding site from Acanthamoeba CARMIL and mouse CARMIL-1, respectively. This improved method for CP purification should facilitate the in vitro analysis of CP structure, function, and regulation.
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Johnson RI, Seppa MJ, Cagan RL. The Drosophila CD2AP/CIN85 orthologue Cindr regulates junctions and cytoskeleton dynamics during tissue patterning. ACTA ACUST UNITED AC 2008; 180:1191-204. [PMID: 18362180 PMCID: PMC2290846 DOI: 10.1083/jcb.200706108] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Developing tissues require cells to undergo intricate processes to shift into appropriate niches. This requires a functional connection between adhesion-mediating events at the cell surface and a cytoskeletal reorganization to permit directed movement. A small number of proteins are proposed to link these processes. Here, we identify one candidate, Cindr, the sole Drosophila melanogaster member of the CD2AP/CIN85 family (this family has been previously implicated in a variety of processes). Using D. melanogaster retina, we demonstrate that Cindr links cell surface junctions (E-cadherin) and adhesion (Roughest) with multiple components of the actin cytoskeleton. Reducing cindr activity leads to defects in local cell movement and, consequently, tissue patterning and cell death. Cindr activity is required for normal localization of Drosophila E-cadherin and Roughest, and we show additional physical and functional links to multiple components of the actin cytoskeleton, including the actin-capping proteins capping protein alpha and capping protein beta. Together, these data demonstrate that Cindr is involved in dynamic cell rearrangement in an emerging epithelium.
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Affiliation(s)
- Ruth I Johnson
- Department of Developmental and Regenerative Biology, Mount Sinai Medical School, New York, NY 10029, USA
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Cooper JA, Sept D. New insights into mechanism and regulation of actin capping protein. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 267:183-206. [PMID: 18544499 DOI: 10.1016/s1937-6448(08)00604-7] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The heterodimeric actin capping protein, referred to here as "CP," is an essential element of the actin cytoskeleton, binding to the barbed ends of actin filaments and regulating their polymerization. In vitro, CP has a critical role in the dendritic nucleation process of actin assembly mediated by Arp2/3 complex, and in vivo, CP is important for actin assembly and actin-based process of morphogenesis and differentiation. Recent studies have provided new insight into the mechanism of CP binding the barbed end, which raises new possibilities for the dynamics of CP and actin in cells. In addition, a number of molecules that bind and regulate CP have been discovered, suggesting new ideas for how CP may integrate into diverse processes of cell physiology.
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Affiliation(s)
- John A Cooper
- Department of Cell Biology, Washington University, St. Louis, MO 63110, USA
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Morita T, Mayanagi T, Sobue K. Reorganization of the actin cytoskeleton via transcriptional regulation of cytoskeletal/focal adhesion genes by myocardin-related transcription factors (MRTFs/MAL/MKLs). Exp Cell Res 2007; 313:3432-45. [PMID: 17714703 DOI: 10.1016/j.yexcr.2007.07.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 07/07/2007] [Accepted: 07/10/2007] [Indexed: 01/27/2023]
Abstract
RhoA is a crucial regulator of stress fiber and focal adhesion formation through the activation of actin nucleation and polymerization. It also regulates the nuclear translocation of myocardin-related transcription factor-A and -B (MRTF-A/B, MAL or MKL 1/2), which are co-activators of serum response factor (SRF). In dominant-negative MRTF-A (DN-MRTF-A)-expressing NIH 3T3 cell lines, the expressions of several cytoskeletal/focal adhesion genes were down-regulated, and the formation of stress fiber and focal adhesion was severely diminished. MRTF-A/B-knockdown cells also exhibited such cytoskeletal defects. In reporter assays, both RhoA and MRTF-A enhanced promoter activities of these genes in a CArG-box-dependent manner, and DN-MRTF-A inhibited the RhoA-mediated activation of these promoters. In dominant-negative RhoA (RhoA-N19)-expressing NIH 3T3 cell lines, the nuclear translocation of MRTF-A/B was predominantly prevented, resulting in the reduced expression of cytoskeletal/focal adhesion proteins. Further, constitutive-active MRTF-A/B increased the expression of endogenous cytoskeletal/focal adhesion proteins, and thereby rescued the defective phenotype of stress fibers and focal adhesions in RhoA-N19 expressing cells. These results indicate that MRTF-A/B act as pivotal mediators of stress fiber and focal adhesion formation via the transcriptional regulation of a subset of cytoskeletal/focal adhesion genes.
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Affiliation(s)
- Tsuyoshi Morita
- Depertment of Neuroscience (D13), Osaka University Graduate School of Medicine, Yamadaoka 2-2, Suita, Osaka, Japan
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Ren N, Charlton J, Adler PN. The flare gene, which encodes the AIP1 protein of Drosophila, functions to regulate F-actin disassembly in pupal epidermal cells. Genetics 2007; 176:2223-34. [PMID: 17565945 PMCID: PMC1950627 DOI: 10.1534/genetics.107.072959] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Adult Drosophila are decorated with several types of polarized cuticular structures, such as hairs and bristles. The morphogenesis of these takes place in pupal cells and is mediated by the actin and microtubule cytoskeletons. Mutations in flare (flr) result in grossly abnormal epidermal hairs. We report here that flr encodes the Drosophila actin interacting protein 1 (AIP1). In other systems this protein has been found to promote cofilin-mediated F-actin disassembly. In Drosophila cofilin is encoded by twinstar (tsr). We show that flr mutations result in increased levels of F-actin accumulation and increased F-actin stability in vivo. Further, flr is essential for cell proliferation and viability and for the function of the frizzled planar cell polarity system. All of these phenotypes are similar to those seen for tsr mutations. This differs from the situation in yeast where cofilin is essential while aip1 mutations result in only subtle defects in the actin cytoskeleton. Surprisingly, we found that mutations in flr and tsr also result in greatly increased tubulin staining, suggesting a tight linkage between the actin and microtubule cytoskeleton in these cells.
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Affiliation(s)
- Nan Ren
- Biology Department, Institute for Morphogenesis and Regenerative Medicine and Cancer Center, University of Virginia, Charlottesville, VA 22903, USA
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Matsuo K, Xiang Y, Nakamura H, Masuko K, Yudoh K, Noyori K, Nishioka K, Saito T, Kato T. Identification of novel citrullinated autoantigens of synovium in rheumatoid arthritis using a proteomic approach. Arthritis Res Ther 2007; 8:R175. [PMID: 17125526 PMCID: PMC1794520 DOI: 10.1186/ar2085] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 11/02/2006] [Accepted: 11/27/2006] [Indexed: 11/21/2022] Open
Abstract
Recently, autoantibodies to some citrullinated autoantigens have been reported to be specific for rheumatoid arthritis (RA). However, an entire profile of and autoimmunity of the citrullinated proteins have been poorly understood. To understand the profile, we examined citrullinated autoantigens by a proteomic approach and further investigated the significance of citrullination in antigenicity of one of the autoantigens. Specifically, we detected citrullinated autoantigens in synovial tissue of a patient with RA by two-dimensional electrophoresis and Western blotting by using pooled sera from five patients with RA and anti-citrulline antibodies. After identifying the detected autoantigens by mass spectrometry, we investigated the contribution of citrullination to autoantigenicity by using a recombinant protein with or without citrullination on one of the identified novel citrullinated autoantigens. As a result, we found 51 citrullinated protein spots. Thirty (58.8%) of these spots were autoantigenic. We identified 13 out of the 30 detected citrullinated autoantigenic proteins. They contained three fibrinogen derivatives and several novel citrullinated autoantigens (for example, asporin and F-actin capping protein α-1 subunit [CapZα-1]). We further analyzed the contribution of citrullination to autoantigenicity in one of the detected citrullinated autoantigens, CapZα-1. As a result, frequencies of autoantibodies to non-citrullinated CapZα-1 were 36.7% in the RA group tested, 10.7% in the osteoarthritis (OA) group, and 6.5% in healthy donors. On the other hand, those to citrullinated CapZα-1 were 53.3% in the RA group, 7.1% in the OA group, and 6.5% in the healthy donors. This shows that autoantigenicity of citrullinated or non-citrullinated CapZα-1 is relevant to RA. The antibody titers to the citrullinated CapZα-1 were significantly higher than those to the non-citrullinated CapZα-1 in 36.7% of patients; however, the other patients showed almost equal antibody titers to both citrullinated and non-citrullinated CapZα-1. Therefore, the autoantibodies would target citrulline-related and/or citrulline-unrelated epitope(s) of CapZα-1. In conclusion, we report a profile of citrullinated autoantigens for the first time. Even though citrullination is closely related to autoantigenicity, citrullination would not always produce autoantigenicity in RA. Citrullinated and non-citrullinated autoantigens/autoepitopes would have different pathological roles in RA.
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Affiliation(s)
- Kosuke Matsuo
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
- Musculoskeletal Science, Yokohama City University Graduate School of Medicine, Fukuura3-9, Kanazawa, Yokohama, Kanagawa 236-0004, Japan
| | - Yang Xiang
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
| | - Hiroshi Nakamura
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
| | - Kayo Masuko
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
| | - Kazuo Yudoh
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
| | - Koji Noyori
- Musculoskeletal Science, Yokohama City University Graduate School of Medicine, Fukuura3-9, Kanazawa, Yokohama, Kanagawa 236-0004, Japan
| | - Kusuki Nishioka
- Department of Frontier Medicine, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
| | - Tomoyuki Saito
- Musculoskeletal Science, Yokohama City University Graduate School of Medicine, Fukuura3-9, Kanazawa, Yokohama, Kanagawa 236-0004, Japan
| | - Tomohiro Kato
- Department of Bioregulation & Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Sugao 2-16-1, Miyamae, Kawasaki, Kanagawa 216-8512, Japan
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Janody F, Treisman JE. Actin capping protein alpha maintains vestigial-expressing cells within the Drosophila wing disc epithelium. Development 2006; 133:3349-57. [PMID: 16887822 PMCID: PMC1544359 DOI: 10.1242/dev.02511] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tissue patterning must be translated into morphogenesis through cell shape changes mediated by remodeling of the actin cytoskeleton. We have found that Capping protein alpha (Cpa) and Capping protein beta (Cpb), which prevent extension of the barbed ends of actin filaments, are specifically required in the wing blade primordium of the Drosophila wing disc. cpa or cpb mutant cells in this region, but not in the remainder of the wing disc, are extruded from the epithelium and undergo apoptosis. Excessive actin filament polymerization is not sufficient to explain this phenotype, as loss of Cofilin or Cyclase-associated protein does not cause cell extrusion or death. Misexpression of Vestigial, the transcription factor that specifies the wing blade, both increases cpa transcription and makes cells dependent on cpa for their maintenance in the epithelium. Our results suggest that Vestigial specifies the cytoskeletal changes that lead to morphogenesis of the adult wing.
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Affiliation(s)
- Florence Janody
- Developmental Biology Institute of Marseille Luminy, UMR6216 - Case 907, Parc Scientific de Luminy, 13288 Marseille Cedex 09, France.
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43
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Nakano K, Mabuchi I. Actin-capping protein is involved in controlling organization of actin cytoskeleton together with ADF/cofilin, profilin and F-actin crosslinking proteins in fission yeast. Genes Cells 2006; 11:893-905. [PMID: 16866873 DOI: 10.1111/j.1365-2443.2006.00987.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Actin-capping protein (CP) is a heterodimeric protein which is expressed in various eukaryotic cells. CP binds to the barbed end of the actin filaments in vitro and inhibits both the association and dissociation of actin monomers at this end. However, the cellular role of CP has not been uncovered. Here we investigated the function of CP in fission yeast cells. The fission yeast CP is composed of Acp1 and Acp2. It was found that Acp2 accumulated as cortical dots at the cell ends during interphase and the mid-region of mitotic cells, which disappeared in the absence of Acp1 or F-actin. Acp1 and Acp2, when co-over-expressed, decreased F-actin structures in cells, and cytokinesis was often interrupted in these cells. On the other hand, disruption of one of the CP genes affected the distribution of F-actin patches at cell ends and decreased the rate of actin depolymerization in vivo. Moreover, genetic analysis showed that CP controls actin dynamics together with ADF/cofilin and profilin. In addition, CP is likely involved in assembling the F-actin contractile ring and F-actin patch with F-actin-crosslinking proteins.
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Affiliation(s)
- Kentaro Nakano
- Division of Biology, Department of Life Sciences, School of Arts and Sciences, University of Tokyo, Komaba, Tokyo 153-8902, Japan.
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44
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Frank DJ, Hopmann R, Lenartowska M, Miller KG. Capping protein and the Arp2/3 complex regulate nonbundle actin filament assembly to indirectly control actin bundle positioning during Drosophila melanogaster bristle development. Mol Biol Cell 2006; 17:3930-9. [PMID: 16822838 PMCID: PMC1593168 DOI: 10.1091/mbc.e06-06-0500] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Drosophila melanogaster bristle development is dependent on actin assembly, and prominent actin bundles form against the elongating cell membrane, giving the adult bristle its characteristic grooved pattern. Previous work has demonstrated that several actin-regulating proteins are required to generate normal actin bundles. Here we have addressed how two actin regulators, capping protein, a barbed end binding protein, and the Arp2/3 complex, a potent actin assembly nucleator, function to generate properly organized bundles. As predicted from studies in motile cells, we find that capping protein and the Arp2/3 complex act antagonistically to one another during bristle development. However, these proteins do not primarily act directly on bundles, but rather on a dynamic population of actin filaments that are not part of the bundles. These nonbundle filaments, termed snarls, play an important role in determining the number and spacing of the actin bundles. Reduction of capping protein leads to an increase in snarls, which prevents actin bundles from properly attaching to the membrane. Conversely, loss of an Arp2/3 complex component leads to a loss of snarls and accumulation of excess membrane-attached bundles. These results indicate that in nonmotile cells dynamic actin filaments can function to regulate the positioning of stable actin structures. In addition, our results suggest that the Arpc1 subunit may have an additional function, independent of the rest of the Arp2/3 complex.
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Affiliation(s)
- Deborah J. Frank
- *Department of Biology, Washington University, St. Louis, MO 63130; and
| | - Roberta Hopmann
- *Department of Biology, Washington University, St. Louis, MO 63130; and
| | - Marta Lenartowska
- *Department of Biology, Washington University, St. Louis, MO 63130; and
- Laboratory of Developmental Biology, Institute of General and Molecular Biology, Nicolaus Copernicus University, 87-100 Torun, Poland
| | - Kathryn G. Miller
- *Department of Biology, Washington University, St. Louis, MO 63130; and
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45
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Shapiro RS, Anderson KV. DrosophilaIk2, a member of the IκB kinase family, is required for mRNA localization during oogenesis. Development 2006; 133:1467-75. [PMID: 16540511 DOI: 10.1242/dev.02318] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In both Drosophila and mammals, IκB kinases (IKKs) regulate the activity of Rel/NF-κB transcription factors by targeting their inhibitory partner proteins, IκBs, for degradation. We identified mutations in ik2, the gene that encodes one of two Drosophila IKKs, and found that the gene is essential for viability. During oogenesis, ik2 is required in an NF-κB-independent process that is essential for the localization of oskar and gurken mRNAs; as a result, females that lack ik2 in the germline produce embryos that are both bicaudal and ventralized. The abnormal RNA localization in ik2 mutant oocytes can be attributed to defects in the organization of microtubule minus-ends. In addition, both mutant oocytes and mutant escaper adults have abnormalities in the organization of the actin cytoskeleton. These data suggest that this IκB kinase has an NF-κB-independent role in mRNA localization and helps to link microtubule minus-ends to the oocyte cortex, a novel function of the IKK family.
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Affiliation(s)
- Risa S Shapiro
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10021, USA
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46
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Abstract
Acanthamoeba CARMIL was previously shown to co-purify with capping protein (CP) and to bind pure CP. Here we show that this interaction inhibits the barbed end-capping activity of CP. Even more strikingly, this interaction drives the uncapping of actin filaments previously capped with CP. These activities are CP-specific; CARMIL does not inhibit the capping activities of either gelsolin or CapG and does not uncap gelsolin-capped filaments. Although full-length (FL) CARMIL (residues 1-1121) possesses both anti-CP activities, C-terminal fragments like glutathione S-transferase (GST)-P (940-1121) that contain the CARMIL CP binding site are at least 10 times more active. We localized the full activities of GST-P to its C-terminal 51 residues (1071-1121). This sequence contains a stretch of 25 residues that is highly conserved in CARMIL proteins from protozoa, flies, worms, and vertebrates (CARMIL Homology domain 3; CAH3). Point mutations showed that the majority of the most highly conserved residues within CAH3 are critical for the anti-CP activity of GST-AP (862-1121). Finally, we found that GST-AP binds CP approximately 20-fold more tightly than does FL-CARMIL. This observation together with the elevated activities of C-terminal fragments relative to FL-CARMIL suggests that FL-CARMIL might exist primarily in an autoinhibited state. Consistent with this idea, proteolytic cleavage of FL-CARMIL with thrombin generated an approximately 14-kDa C-terminal fragment that expresses full anti-CP activities. We propose that, after some type of physiological activation event, FL-CARMIL could function in vivo as a potent CP antagonist. Given the pivotal role that CP plays in determining the global actin phenotype of cells, our results suggest that CARMIL may play an important role in the physiological regulation of actin assembly.
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Affiliation(s)
- Takehito Uruno
- Laboratory of Cell Biology, Section on Molecular Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Rm. 2523, 9000 Rockville Pike, Bethesda, MD 20892-8017, USA
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47
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Yang C, Pring M, Wear MA, Huang M, Cooper JA, Svitkina TM, Zigmond SH. Mammalian CARMIL inhibits actin filament capping by capping protein. Dev Cell 2005; 9:209-21. [PMID: 16054028 PMCID: PMC2628720 DOI: 10.1016/j.devcel.2005.06.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Revised: 05/05/2005] [Accepted: 06/30/2005] [Indexed: 11/30/2022]
Abstract
Actin polymerization in cells occurs via filament elongation at the barbed end. Proteins that cap the barbed end terminate this elongation. Heterodimeric capping protein (CP) is an abundant and ubiquitous protein that caps the barbed end. We find that the mouse homolog of the adaptor protein CARMIL (mCARMIL) binds CP with high affinity and decreases its affinity for the barbed end. Addition of mCARMIL to cell extracts increases the rate and extent of Arp2/3 or spectrin-actin seed-induced polymerization. In cells, GFP-mCARMIL concentrates in lamellipodia and increases the fraction of cells with large lamellipodia. Decreasing mCARMIL levels by siRNA transfection lowers the F-actin level and slows cell migration through a mechanism that includes decreased lamellipodia protrusion. This phenotype is reversed by full-length mCARMIL but not mCARMIL lacking the domain that binds CP. Thus, mCARMIL is a key regulator of CP and has profound effects on cell behavior.
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Affiliation(s)
- Changsong Yang
- Biology Department, University of Pennsylvania, Philadelphia, PA 19104, USA.
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48
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Delalle I, Pfleger CM, Buff E, Lueras P, Hariharan IK. Mutations in the Drosophila orthologs of the F-actin capping protein alpha- and beta-subunits cause actin accumulation and subsequent retinal degeneration. Genetics 2005; 171:1757-65. [PMID: 16143599 PMCID: PMC1456101 DOI: 10.1534/genetics.105.049213] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The progression of several human neurodegenerative diseases is characterized by the appearance of intracellular inclusions or cytoskeletal abnormalities. An important question is whether these abnormalities actually contribute to the degenerative process or whether they are merely manifestations of cells that are already destined for degeneration. We have conducted a large screen in Drosophila for mutations that alter the growth or differentiation of cells during eye development. We have used mitotic recombination to generate patches of homozygous mutant cells. In our entire screen, mutations in only two different loci, burned (bnd) and scorched (scrd), resulted in eyes in which the mutant patches appeared black and the mutant tissue appeared to have undergone degeneration. In larval imaginal discs, growth and cell fate specification occur normally in mutant cells, but there is an accumulation of F-actin. Mutant cells degenerate much later during the pupal phase of development. burned mutations are allelic to mutations in the previously described cpb locus that encodes the beta-subunit of the F-actin capping protein, while scorched mutations disrupt the gene encoding its alpha-subunit (cpa). The alpha/beta-heterodimer caps the barbed ends of an actin filament and restricts its growth. In its absence, cells progressively accumulate actin filaments and eventually die. A possible role for their human orthologs in neurodegenerative disease merits further investigation.
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Affiliation(s)
- Ivana Delalle
- Massachusetts General Hospital Cancer Center, Charlestown, MA 02129, USA
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49
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He Y, Emoto K, Fang X, Ren N, Tian X, Jan YN, Adler PN. Drosophila Mob family proteins interact with the related tricornered (Trc) and warts (Wts) kinases. Mol Biol Cell 2005; 16:4139-52. [PMID: 15975907 PMCID: PMC1196325 DOI: 10.1091/mbc.e05-01-0018] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The function of Tricornered (Trc), the Drosophila Ndr (Nuclear Dbf2-related) serine/threonine protein kinase, is required for the normal morphogenesis of a variety of polarized outgrowths including epidermal hairs, bristles, arista laterals, and dendrites. In yeast the Trc homolog Cbk1 needs to bind Mob2 to activate the RAM pathway. In this report, we provide genetic and biochemical data that Drosophila Trc also interacts with and is activated by Drosophila Dmob proteins. In addition, Drosophila Mob proteins appear to interact with the related Warts/Lats kinase, which functions as a tumor suppressor in flies and mammals. Interestingly, the overgrowth tumor phenotype that results from mutations in Dmob1 (mats) was only seen in genetic mosaics and not when the entire animal was mutant. We conclude that unlike in yeast, in Drosophila individual Mob proteins interact with multiple kinases and that individual NDR family kinases interact with multiple Mob proteins. We further provide evidence that Mo25, the Drosophila homolog of the RAM pathway hym1 gene does not function along with Trc.
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Affiliation(s)
- Ying He
- Department of Biology, Center for Morphogenesis and Regenerative Medicine and Cancer Center, University of Virginia, Charlottesville, VA 22903, USA
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50
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Kovar DR, Wu JQ, Pollard TD. Profilin-mediated competition between capping protein and formin Cdc12p during cytokinesis in fission yeast. Mol Biol Cell 2005; 16:2313-24. [PMID: 15743909 PMCID: PMC1087237 DOI: 10.1091/mbc.e04-09-0781] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Fission yeast capping protein SpCP is a heterodimer of two subunits (Acp1p and Acp2p) that binds actin filament barbed ends. Neither acp1 nor acp2 is required for viability, but cells lacking either or both subunits have cytokinesis defects under stressful conditions, including elevated temperature, osmotic stress, or in combination with numerous mild mutations in genes important for cytokinesis. Defects arise as the contractile ring constricts and disassembles, resulting in delays in cell separation. Genetic and biochemical interactions show that the cytokinesis formin Cdc12p competes with capping protein for actin filament barbed ends in cells. Deletion of acp2 partly suppresses cytokinesis defects in temperature-sensitive cdc12-112 cells and mild overexpression of capping protein kills cdc12-112 cells. Biochemically, profilin has opposite effects on filaments capped with Cdc12p and capping protein. Profilin depolymerizes actin filaments capped by capping protein but allows filaments capped by Cdc12p to grow at their barbed ends. Once associated with a barbed end, either Cdc12p or capping protein prevents the other from influencing polymerization at that end. Given that capping protein arrives at the division site 20 min later than Cdc12p, capping protein may slowly replace Cdc12p on filament barbed ends in preparation for filament disassembly during ring constriction.
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Affiliation(s)
- David R Kovar
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA
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