1
|
Gerstner JR, Flores CC, Lefton M, Rogers B, Davis CJ. FABP7: a glial integrator of sleep, circadian rhythms, plasticity, and metabolic function. Front Syst Neurosci 2023; 17:1212213. [PMID: 37404868 PMCID: PMC10315501 DOI: 10.3389/fnsys.2023.1212213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/02/2023] [Indexed: 07/06/2023] Open
Abstract
Sleep and circadian rhythms are observed broadly throughout animal phyla and influence neural plasticity and cognitive function. However, the few phylogenetically conserved cellular and molecular pathways that are implicated in these processes are largely focused on neuronal cells. Research on these topics has traditionally segregated sleep homeostatic behavior from circadian rest-activity rhythms. Here we posit an alternative perspective, whereby mechanisms underlying the integration of sleep and circadian rhythms that affect behavioral state, plasticity, and cognition reside within glial cells. The brain-type fatty acid binding protein, FABP7, is part of a larger family of lipid chaperone proteins that regulate the subcellular trafficking of fatty acids for a wide range of cellular functions, including gene expression, growth, survival, inflammation, and metabolism. FABP7 is enriched in glial cells of the central nervous system and has been shown to be a clock-controlled gene implicated in sleep/wake regulation and cognitive processing. FABP7 is known to affect gene transcription, cellular outgrowth, and its subcellular localization in the fine perisynaptic astrocytic processes (PAPs) varies based on time-of-day. Future studies determining the effects of FABP7 on behavioral state- and circadian-dependent plasticity and cognitive processes, in addition to functional consequences on cellular and molecular mechanisms related to neural-glial interactions, lipid storage, and blood brain barrier integrity will be important for our knowledge of basic sleep function. Given the comorbidity of sleep disturbance with neurological disorders, these studies will also be important for our understanding of the etiology and pathophysiology of how these diseases affect or are affected by sleep.
Collapse
Affiliation(s)
- Jason R. Gerstner
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
- Steve Gleason Institute for Neuroscience, Spokane, WA, United States
- Sleep and Performance Research Center, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - Carlos C. Flores
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - Micah Lefton
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - Brooke Rogers
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| | - Christopher J. Davis
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
- Steve Gleason Institute for Neuroscience, Spokane, WA, United States
- Sleep and Performance Research Center, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, United States
| |
Collapse
|
2
|
Cytoplasmic Tail Truncation Stabilizes S1-S2 Association and Enhances S Protein Incorporation into SARS-CoV-2 Pseudovirions. J Virol 2023; 97:e0165022. [PMID: 36790205 PMCID: PMC10062125 DOI: 10.1128/jvi.01650-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Truncations of the cytoplasmic tail (CT) of entry proteins of enveloped viruses dramatically increase the infectivity of pseudoviruses (PVs) bearing these proteins. Several mechanisms have been proposed to explain this enhanced entry, including an increase in cell surface expression. However, alternative explanations have also been forwarded, and the underlying mechanisms for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S protein remain undetermined. Here, we show that the partial or complete deletion of the CT (residues 19 to 35) does not modify SARS-CoV-2 S protein expression on the cell surface when the S2 subunit is measured, whereas it is significantly increased when the S1 subunit is measured. We also show that the higher level of S1 in these CT-truncated S proteins reflects the decreased dissociation of the S1 subunit from the S2 subunit. In addition, we demonstrate that CT truncation further promotes S protein incorporation into PV particles, as indicated by biochemical analyses and cryo-electron microscopy. Thus, our data show that two distinct mechanisms contribute to the markedly increased infectivity of PVs carrying CT-truncated SARS-CoV-2 S proteins and help clarify the interpretation of the results of studies employing such PVs. IMPORTANCE Various forms of PVs have been used as tools to evaluate vaccine efficacy and study virus entry steps. When PV infectivity is inherently low, such as that of SARS-CoV-2, a CT-truncated version of the viral entry glycoprotein is widely used to enhance PV infectivity, but the mechanism underlying this enhanced PV infectivity has been unclear. Here, our study identified two mechanisms by which the CT truncation of the SARS-CoV-2 S protein dramatically increases PV infectivity: a reduction of S1 shedding and an increase in S protein incorporation into PV particles. An understanding of these mechanisms can clarify the mechanistic bases for the differences observed among various assays employing such PVs.
Collapse
|
3
|
Song M, Suh P. O‐GlcNAcylation regulates lysophosphatidic acid‐induced cell migration by regulating ERM family proteins. FEBS Open Bio 2022; 12:1220-1229. [PMID: 35347892 PMCID: PMC9157403 DOI: 10.1002/2211-5463.13404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 10/04/2021] [Accepted: 03/28/2022] [Indexed: 11/18/2022] Open
Abstract
O‐GlcNAcylation of intracellular proteins (O‐GlcNAc) is a post‐translational modification that often competes with phosphorylation in diverse cellular signaling pathways. Recent studies on human malignant tumors have demonstrated that O‐GlcNAc is implicated in cellular features relevant to metastasis. Here, we report that lysophosphatidic acid (LPA)‐induced ovarian cancer cell (OVCAR‐3) migration is regulated by O‐GlcNAc. We found that O‐GlcNAc modification of ERM family proteins, a membrane‐cytoskeletal crosslinker, was inversely correlated with its phosphorylation status. Moreover, the LPA‐induced formation of membrane protrusion structures, as well as the migration of OVCAR‐3 cells, was reduced by the accumulation of O‐GlcNAc. Collectively, these findings suggest that O‐GlcNAc is an essential signaling element controlling ERM family proteins involved in OVCAR‐3 cell migration.
Collapse
Affiliation(s)
- Minseok Song
- Department of Life Sciences Yeungnam University Gyeongsan Gyeongbuk 38541 South Korea
| | - Pann‐Ghill Suh
- Korea Basic Science Research Institute (KBRI) Daegu Republic of Korea
| |
Collapse
|
4
|
Hovde MJ, Bolland DE, Armand A, Pitsch E, Bakker C, Kooiker AJ, Provost JJ, Vaughan RA, Wallert MA, Foster JD. Sodium hydrogen exchanger (NHE1) palmitoylation and potential functional regulation. Life Sci 2022; 288:120142. [PMID: 34774621 PMCID: PMC8692447 DOI: 10.1016/j.lfs.2021.120142] [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: 08/16/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 01/03/2023]
Abstract
AIMS Determine the effect of palmitoylation on the sodium hydrogen exchanger isoform 1 (NHE1), a member of the SLC9 family. MAIN METHODS NHE1 expressed in native rat tissues or in heterologous cells was assessed for palmitoylation by acyl-biotinyl exchange (ABE) and metabolic labeling with [3H]palmitate. Cellular palmitoylation was inhibited using 2-bromopalmitate (2BP) followed by determination of NHE1 palmitoylation status, intracellular pH, stress fiber formation, and cell migration. In addition, NHE1 was activated with LPA treatment followed by determination of NHE1 palmitoylation status and LPA-induced change in intracellular pH was determined in the presence and absence of preincubation with 2BP. KEY FINDINGS In this study we demonstrate for the first time that NHE1 is palmitoylated in both cells and rat tissue, and that processes controlled by NHE1 including intracellular pH (pHi), stress fiber formation, and cell migration, are regulated in concert with NHE1 palmitoylation status. Importantly, LPA stimulates NHE1 palmitoylation, and 2BP pretreatment dampens LPA-induced increased pHi which is dependent on the presence of NHE1. SIGNIFICANCE Palmitoylation is a reversible lipid modification that regulates an array of critical protein functions including activity, trafficking, membrane microlocalization and protein-protein interactions. Our results suggest that palmitoylation of NHE1 and other control/signaling proteins play a major role in NHE1 regulation that could significantly impact multiple critical cellular functions.
Collapse
Affiliation(s)
- Moriah J Hovde
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States of America.
| | - Danielle E Bolland
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States of America.
| | - Aryna Armand
- Department of Chemistry and Biochemistry, University of San Diego, San Diego, CA 92110, United States of America.
| | - Emily Pitsch
- Department of Chemistry and Biochemistry, University of San Diego, San Diego, CA 92110, United States of America
| | - Clare Bakker
- Department of Chemistry and Biochemistry, University of San Diego, San Diego, CA 92110, United States of America.
| | - Amanda J Kooiker
- Biology Department, Bemidji State University, Bemidji, MN 56601, United States of America.
| | - Joseph J Provost
- Department of Chemistry and Biochemistry, University of San Diego, San Diego, CA 92110, United States of America.
| | - Roxanne A Vaughan
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States of America.
| | - Mark A Wallert
- Biology Department, Bemidji State University, Bemidji, MN 56601, United States of America.
| | - James D Foster
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States of America.
| |
Collapse
|
5
|
Yang F, Lin J, Chen W. Post-translational modifications in T cells in systemic erythematosus lupus. Rheumatology (Oxford) 2021; 60:2502-2516. [PMID: 33512488 DOI: 10.1093/rheumatology/keab095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/21/2021] [Accepted: 01/23/2021] [Indexed: 02/07/2023] Open
Abstract
Systemic erythematosus lupus (SLE) is a classic autoimmune disease characterized by multiple autoantibodies and immune-mediated tissue damage. The aetiology of this disease is still unclear. A new drug, belimumab, which acts against the B-lymphocyte stimulator (BLyS), can effectively improve the condition of SLE patients, but it cannot resolve all SLE symptoms. The discovery of novel, precise therapeutic targets is urgently needed. It is well known that abnormal T-cell function is one of the most crucial factors contributing to the pathogenesis of SLE. Protein post-translational modifications (PTMs), including phosphorylation, glycosylation, acetylation, methylation, ubiquitination and SUMOylation have been emphasized for their roles in activating protein activity, maintaining structural stability, regulating protein-protein interactions and mediating signalling pathways, in addition to other biological functions. Summarizing the latest data in this area, this review focuses on the potential roles of diverse PTMs in regulating T-cell function and signalling pathways in SLE pathogenesis, with the goal of identifying new targets for SLE therapy.
Collapse
Affiliation(s)
- Fan Yang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China
| | - Jin Lin
- Division of Rheumatology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Weiqian Chen
- Division of Rheumatology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| |
Collapse
|
6
|
Garland B, Delisle S, Al-Zahrani KN, Pryce BR, Sabourin LA. The Ste20-like kinase - a Jack of all trades? J Cell Sci 2021; 134:261804. [PMID: 33961052 DOI: 10.1242/jcs.258269] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Over the past 20 years, the Ste20-like kinase (SLK; also known as STK2) has emerged as a central regulator of cytoskeletal dynamics. Reorganization of the cytoskeleton is necessary for a plethora of biological processes including apoptosis, proliferation, migration, tissue repair and signaling. Several studies have also uncovered a role for SLK in disease progression and cancer. Here, we review the recent findings in the SLK field and summarize the various roles of SLK in different animal models and discuss the biochemical mechanisms regulating SLK activity. Together, these studies have revealed multiple roles for SLK in coupling cytoskeletal dynamics to cell growth, in muscle repair and in negative-feedback loops critical for cancer progression. Furthermore, the ability of SLK to regulate some systems appears to be kinase activity independent, suggesting that it may be an important scaffold for signal transduction pathways. These various findings reveal highly complex functions and regulation patterns of SLK in development and disease, making it a potential therapeutic target.
Collapse
Affiliation(s)
- Brennan Garland
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Samuel Delisle
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Khalid N Al-Zahrani
- Center for Molecular and Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G1X5, Canada
| | - Benjamin R Pryce
- Department of Pediatrics, Hollings Cancer Center, Medical University of South Carolina,Charleston, SC 29425, USA
| | - Luc A Sabourin
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| |
Collapse
|
7
|
Disruption of the autism-related gene Pak1 causes stereocilia disorganization, hair cell loss, and deafness in mice. J Genet Genomics 2021; 48:324-332. [PMID: 34049799 DOI: 10.1016/j.jgg.2021.03.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/18/2021] [Accepted: 03/12/2021] [Indexed: 01/06/2023]
Abstract
Several clinical studies have reported that hearing loss is correlated with autism in children. However, little is known about the underlying mechanism between hearing loss and autism. p21-activated kinases (PAKs) are a family of serine/threonine kinases that can be activated by multiple signaling molecules, particularly the Rho family of small GTPases. Previous studies have shown that Pak1 mutations are associated with autism. In the present study, we take advantage of Pak1 knockout (Pak1-/-) mice to investigate the role of PAK1 in hearing function. We find that PAK1 is highly expressed in the postnatal mouse cochlea and that PAK1 deficiency leads to hair cell (HC) apoptosis and severe hearing loss. Further investigation indicates that PAK1 deficiency downregulates the phosphorylation of cofilin and ezrin-radixin-moesin and the expression of βII-spectrin, which further decreases the HC synapse density in the basal turn of cochlea and disorganized the HC stereocilia in all three turns of cochlea in Pak1-/- mice. Overall, our work demonstrates that the autism-related gene Pak1 plays a crucial role in hearing function. As the first candidate gene linking autism and hearing loss, Pak1 may serve as a potential target for the clinical diagnosis of autism-related hearing loss.
Collapse
|
8
|
Molecular basis of functional exchangeability between ezrin and other actin-membrane associated proteins during cytokinesis. Exp Cell Res 2021; 403:112600. [PMID: 33862101 DOI: 10.1016/j.yexcr.2021.112600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/03/2021] [Accepted: 04/05/2021] [Indexed: 01/09/2023]
Abstract
The mechanism that mediates the interaction between the contractile ring and the plasma membrane during cytokinesis remains elusive. We previously found that ERM (Ezrin/Radixin/Moesin) proteins, which usually mediate cellular pole contraction, become over-accumulated at the cell equator and support furrow ingression upon the loss of other actin-membrane associated proteins, anillin and supervillin. In this study, we addressed the molecular basis of the exchangeability between ezrin and other actin-membrane associated proteins in mediating cortical contraction during cytokinesis. We found that depletion of anillin and supervillin caused over-accumulation of the membrane-associated FERM domain and actin-binding C-terminal domain (C-term) of ezrin at the cleavage furrow, respectively. This finding suggests that ezrin differentially shares its binding sites with these proteins on the actin cytoskeleton or inner membrane surface. Using chimeric mutants, we found that ezrin C-term, but not the FERM domain, can substitute for the corresponding anillin domains in cytokinesis and cell proliferation. On the other hand, either the membrane-associated or the actin/myosin-binding domains of anillin could not substitute for the corresponding ezrin domains in controlling cortical blebbing at the cell poles. Our results highlight specific designs of actin- or membrane-associated moieties of different actin-membrane associated proteins with limited exchangeability, which enables them to support diverse cortical activities on the shared actin-membrane interface during cytokinesis.
Collapse
|
9
|
Koltai T, Reshkin SJ, Carvalho TMA, Cardone RA. Targeting the Stromal Pro-Tumoral Hyaluronan-CD44 Pathway in Pancreatic Cancer. Int J Mol Sci 2021; 22:3953. [PMID: 33921242 PMCID: PMC8069142 DOI: 10.3390/ijms22083953] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 02/07/2023] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies. Present-day treatments have not shown real improvements in reducing the high mortality rate and the short survival of the disease. The average survival is less than 5% after 5 years. New innovative treatments are necessary to curtail the situation. The very dense pancreatic cancer stroma is a barrier that impedes the access of chemotherapeutic drugs and at the same time establishes a pro-proliferative symbiosis with the tumor, thus targeting the stroma has been suggested by many authors. No ideal drug or drug combination for this targeting has been found as yet. With this goal in mind, here we have explored a different complementary treatment based on abundant previous publications on repurposed drugs. The cell surface protein CD44 is the main receptor for hyaluronan binding. Many malignant tumors show over-expression/over-activity of both. This is particularly significant in pancreatic cancer. The independent inhibition of hyaluronan-producing cells, hyaluronan synthesis, and/or CD44 expression, has been found to decrease the tumor cell's proliferation, motility, invasion, and metastatic abilities. Targeting the hyaluronan-CD44 pathway seems to have been bypassed by conventional mainstream oncological practice. There are existing drugs that decrease the activity/expression of hyaluronan and CD44: 4-methylumbelliferone and bromelain respectively. Some drugs inhibit hyaluronan-producing cells such as pirfenidone. The association of these three drugs has never been tested either in the laboratory or in the clinical setting. We present a hypothesis, sustained by hard experimental evidence, suggesting that the simultaneous use of these nontoxic drugs can achieve synergistic or added effects in reducing invasion and metastatic potential, in PDAC. A non-toxic, low-cost scheme for inhibiting this pathway may offer an additional weapon for treating pancreatic cancer.
Collapse
Affiliation(s)
| | - Stephan Joel Reshkin
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (T.M.A.C.); (R.A.C.)
| | - Tiago M. A. Carvalho
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (T.M.A.C.); (R.A.C.)
| | - Rosa A. Cardone
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (T.M.A.C.); (R.A.C.)
| |
Collapse
|
10
|
Ernest James Phillips T, Maguire E. Phosphoinositides: Roles in the Development of Microglial-Mediated Neuroinflammation and Neurodegeneration. Front Cell Neurosci 2021; 15:652593. [PMID: 33841102 PMCID: PMC8032904 DOI: 10.3389/fncel.2021.652593] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Microglia are increasingly recognized as vital players in the pathology of a variety of neurodegenerative conditions including Alzheimer’s (AD) and Parkinson’s (PD) disease. While microglia have a protective role in the brain, their dysfunction can lead to neuroinflammation and contributes to disease progression. Also, a growing body of literature highlights the seven phosphoinositides, or PIPs, as key players in the regulation of microglial-mediated neuroinflammation. These small signaling lipids are phosphorylated derivates of phosphatidylinositol, are enriched in the brain, and have well-established roles in both homeostasis and disease.Disrupted PIP levels and signaling has been detected in a variety of dementias. Moreover, many known AD disease modifiers identified via genetic studies are expressed in microglia and are involved in phospholipid metabolism. One of these, the enzyme PLCγ2 that hydrolyzes the PIP species PI(4,5)P2, displays altered expression in AD and PD and is currently being investigated as a potential therapeutic target.Perhaps unsurprisingly, neurodegenerative conditions exhibiting PIP dyshomeostasis also tend to show alterations in aspects of microglial function regulated by these lipids. In particular, phosphoinositides regulate the activities of proteins and enzymes required for endocytosis, toll-like receptor signaling, purinergic signaling, chemotaxis, and migration, all of which are affected in a variety of neurodegenerative conditions. These functions are crucial to allow microglia to adequately survey the brain and respond appropriately to invading pathogens and other abnormalities, including misfolded proteins. AD and PD therapies are being developed to target many of the above pathways, and although not yet investigated, simultaneous PIP manipulation might enhance the beneficial effects observed. Currently, only limited therapeutics are available for dementia, and although these show some benefits for symptom severity and progression, they are far from curative. Given the importance of microglia and PIPs in dementia development, this review summarizes current research and asks whether we can exploit this information to design more targeted, or perhaps combined, dementia therapeutics. More work is needed to fully characterize the pathways discussed in this review, but given the strength of the current literature, insights in this area could be invaluable for the future of neurodegenerative disease research.
Collapse
Affiliation(s)
| | - Emily Maguire
- UK Dementia Research Institute at Cardiff University, Cardiff, United Kingdom
| |
Collapse
|
11
|
Yan Y, Jaffri SA, Schwirz J, Stein C, Schetelig MF. Identification and characterization of four Drosophila suzukii cellularization genes and their promoters. BMC Genet 2020; 21:146. [PMID: 33339500 PMCID: PMC7747377 DOI: 10.1186/s12863-020-00939-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Background The spotted-wing Drosophila (Drosophila suzukii) is a widespread invasive pest that causes severe economic damage to fruit crops. The early development of D. suzukii is similar to that of other Drosophilids, but the roles of individual genes must be confirmed experimentally. Cellularization genes coordinate the onset of cell division as soon as the invagination of membranes starts around the nuclei in the syncytial blastoderm. The promoters of these genes have been used in genetic pest-control systems to express transgenes that confer embryonic lethality. Such systems could be helpful in sterile insect technique applications to ensure that sterility (bi-sex embryonic lethality) or sexing (female-specific embryonic lethality) can be achieved during mass rearing. The activity of cellularization gene promoters during embryogenesis controls the timing and dose of the lethal gene product. Results Here, we report the isolation of the D. suzukii cellularization genes nullo, serendipity-α, bottleneck and slow-as-molasses from a laboratory strain. Conserved motifs were identified by comparing the encoded proteins with orthologs from other Drosophilids. Expression profiling confirmed that all four are zygotic genes that are strongly expressed at the early blastoderm stage. The 5′ flanking regions from these cellularization genes were isolated, incorporated into piggyBac vectors and compared in vitro for the promoter activities. The Dsnullo promoter showed the highest activity in the cell culture assays using D. melanogaster S2 cells. Conclusions The similarities in the gene coding and 5′ flanking sequence as well as in the expression pattern of the four cellularization genes between D. melanogaster and D. suzukii, suggest that conserved functions may be involved in both species. The high expression level at the early blastoderm stage of the four cellularization genes were confirmed, thus their promoters can be considered in embryonic lethality systems. While the Dsnullo promoter could be a suitable candidate, all reported promoters here are subject to further in vivo analyses before constructing potential pest control systems. Supplementary Information The online version contains supplementary material available at 10.1186/s12863-020-00939-y.
Collapse
Affiliation(s)
- Ying Yan
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394, Giessen, Germany. .,Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 35394, Giessen, Germany.
| | - Syeda A Jaffri
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394, Giessen, Germany
| | - Jonas Schwirz
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 35394, Giessen, Germany
| | - Carl Stein
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394, Giessen, Germany
| | - Marc F Schetelig
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Department of Insect Biotechnology in Plant Protection, Winchesterstr. 2, 35394, Giessen, Germany. .,Fraunhofer Institute for Molecular Biology and Applied Ecology IME, 35394, Giessen, Germany.
| |
Collapse
|
12
|
Targeting Mechanotransduction in Osteosarcoma: A Comparative Oncology Perspective. Int J Mol Sci 2020; 21:ijms21207595. [PMID: 33066583 PMCID: PMC7589883 DOI: 10.3390/ijms21207595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 12/13/2022] Open
Abstract
Mechanotransduction is the process in which cells can convert extracellular mechanical stimuli into biochemical changes within a cell. While this a normal process for physiological development and function in many organ systems, tumour cells can exploit this process to promote tumour progression. Here we summarise the current state of knowledge of mechanotransduction in osteosarcoma (OSA), the most common primary bone tumour, referencing both human and canine models and other similar mesenchymal malignancies (e.g., Ewing sarcoma). Specifically, we discuss the mechanical properties of OSA cells, the pathways that these cells utilise to respond to external mechanical cues, and mechanotransduction-targeting strategies tested in OSA so far. We point out gaps in the literature and propose avenues to address them. Understanding how the physical microenvironment influences cell signalling and behaviour will lead to the improved design of strategies to target the mechanical vulnerabilities of OSA cells.
Collapse
|
13
|
Park JH, Lee C, Han D, Lee JS, Lee KM, Song MJ, Kim K, Lee H, Moon KC, Kim Y, Jung M, Moon JH, Lee H, Ryu HS. Moesin ( MSN) as a Novel Proteome-Based Diagnostic Marker for Early Detection of Invasive Bladder Urothelial Carcinoma in Liquid-Based Cytology. Cancers (Basel) 2020; 12:cancers12041018. [PMID: 32326232 PMCID: PMC7225967 DOI: 10.3390/cancers12041018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/08/2020] [Accepted: 04/16/2020] [Indexed: 12/11/2022] Open
Abstract
Bladder urothelial carcinoma (BUC) is the most lethal malignancy of the urinary tract. Treatment for the disease highly depends on the invasiveness of cancer cells. Therefore, a predictive biomarker needs to be identified for invasive BUC. In this study, we employed proteomics methods on urine liquid-based cytology (LBC) samples and a BUC cell line library to determine a novel predictive biomarker for invasive BUC. Furthermore, an in vitro three-dimensional (3D) invasion study for biological significance and diagnostic validation through immunocytochemistry (ICC) were also performed. The proteomic analysis suggested moesin (MSN) as a potential biomarker to predict the invasiveness of BUC. The in vitro 3D invasion study showed that inhibition of MSN significantly decreased invasiveness in BUC cell lines. Further validation using ICC ultimately confirmed moesin (MSN) as a potential biomarker to predict the invasiveness of BUC (p = 0.023). In conclusion, we suggest moesin as a potential diagnostic marker for early detection of BUC with invasion in LBC and as a potential therapeutic target.
Collapse
Affiliation(s)
- Jeong Hwan Park
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, SMG-SNU Boramae Medical Center, Seoul 07061, Korea
| | - Cheol Lee
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
| | - Dohyun Han
- Division of Clinical Bioinformatics, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea; (D.H.); (K.K.); (H.L.)
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea
| | - Jae Seok Lee
- Department of Pathology, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea;
| | - Kyung Min Lee
- Center for Medical Innovation, Biomedical Research Institute, Seoul National University Hospital, Seoul 03082, Korea;
| | - Min Ji Song
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
| | - Kwangsoo Kim
- Division of Clinical Bioinformatics, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea; (D.H.); (K.K.); (H.L.)
| | - Heonyi Lee
- Division of Clinical Bioinformatics, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea; (D.H.); (K.K.); (H.L.)
- Proteomics Core Facility, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea
| | - Kyung Chul Moon
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
| | - Youngsoo Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, Korea;
| | - Minsun Jung
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
| | - Ji Hye Moon
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
| | - Hyebin Lee
- Department of Radiation Oncology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, 03181, Korea
- Correspondence: (H.L.); (H.S.R.)
| | - Han Suk Ryu
- Department of Pathology, Seoul National University College of Medicine, Seoul 03080, Korea; (J.H.P.); (C.L.); (K.C.M.); (M.J.); (J.H.M.)
- Department of Pathology, Seoul National University Hospital, Seoul 03080, Korea;
- Correspondence: (H.L.); (H.S.R.)
| |
Collapse
|
14
|
Mohanty V, Subbannayya Y, Najar MA, Pinto SM, Kasaragod S, Karuppiah H, Sreeramulu B, Singh KK, Dalal S, Manikkoth S, Arunachalam C, Prasad TSK, Murthy KR. Proteomics and Visual Health Research: Proteome of the Human Sclera Using High-Resolution Mass Spectrometry. ACTA ACUST UNITED AC 2019; 23:98-110. [DOI: 10.1089/omi.2018.0185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Varshasnata Mohanty
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
| | - Yashwanth Subbannayya
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
| | - Mohammed Altaf Najar
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
| | - Sneha M. Pinto
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
| | - Sandeep Kasaragod
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
| | - Hilda Karuppiah
- Department of Zoology, University of Madras, Guindy Campus, Chennai, India
| | | | - Kunal Kumar Singh
- Department of Clinical Biochemistry, Pondicherry University, Puducherry, India
| | - Sunita Dalal
- Department of Biotechnology, Kurukshetra University, Kurukshetra, India
| | - Shyamjith Manikkoth
- Department of Pharmacology, Yenepoya Medical College, Yenepoya (Deemed to be University), Mangalore, India
| | - Cynthia Arunachalam
- Department of Ophthalmology, Yenepoya Medical College, Yenepoya (Deemed to be University), Mangalore, India
| | - Thottethodi Subrahmanya Keshava Prasad
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
- Institute of Bioinformatics, International Tech Park, Bangalore, India
| | - Krishna R. Murthy
- Institute of Bioinformatics, International Tech Park, Bangalore, India
- Vittala International Institute of Ophthalmology, Bangalore, India
- Manipal Academy of Higher Education, Manipal, India
| |
Collapse
|
15
|
Kopp S, Krüger M, Bauer J, Wehland M, Corydon TJ, Sahana J, Nassef MZ, Melnik D, Bauer TJ, Schulz H, Schütte A, Schmitz B, Oltmann H, Feldmann S, Infanger M, Grimm D. Microgravity Affects Thyroid Cancer Cells during the TEXUS-53 Mission Stronger than Hypergravity. Int J Mol Sci 2018; 19:E4001. [PMID: 30545079 PMCID: PMC6321223 DOI: 10.3390/ijms19124001] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/06/2018] [Accepted: 12/09/2018] [Indexed: 12/24/2022] Open
Abstract
Thyroid cancer is the most abundant tumor of the endocrine organs. Poorly differentiated thyroid cancer is still difficult to treat. Human cells exposed to long-term real (r-) and simulated (s-) microgravity (µg) revealed morphological alterations and changes in the expression profile of genes involved in several biological processes. The objective of this study was to examine the effects of short-term µg on poorly differentiated follicular thyroid cancer cells (FTC-133 cell line) resulting from 6 min of exposure to µg on a sounding rocket flight. As sounding rocket flights consist of several flight phases with different acceleration forces, rigorous control experiments are mandatory. Hypergravity (hyper-g) experiments were performed at 18g on a centrifuge in simulation of the rocket launch and s-µg was simulated by a random positioning machine (RPM). qPCR analyses of selected genes revealed no remarkable expression changes in controls as well as in hyper-g samples taken at the end of the first minute of launch. Using a centrifuge initiating 18g for 1 min, however, presented moderate gene expression changes, which were significant for COL1A1, VCL, CFL1, PTK2, IL6, CXCL8 and MMP14. We also identified a network of mutual interactions of the investigated genes and proteins by employing in-silico analyses. Lastly, µg-samples indicated that microgravity is a stronger regulator of gene expression than hyper-g.
Collapse
Affiliation(s)
- Sascha Kopp
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Marcus Krüger
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Johann Bauer
- Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany.
| | - Markus Wehland
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Thomas J Corydon
- Department of Biomedicine, Aarhus University, Wilhelm Meyers Allé 4, DK-8000 Aarhus C, Denmark.
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, 8000 Aarhus C, Denmark.
| | - Jayashree Sahana
- Department of Biomedicine, Aarhus University, Wilhelm Meyers Allé 4, DK-8000 Aarhus C, Denmark.
| | - Mohamed Zakaria Nassef
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Daniela Melnik
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Thomas J Bauer
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Herbert Schulz
- Cologne Center for Genomics, University of Cologne, D-50931 Cologne, Germany.
| | - Andreas Schütte
- Airbus Defence and Space GmbH, Airbus-Allee 1, D-28199 Bremen, Germany.
| | - Burkhard Schmitz
- Airbus Defence and Space GmbH, Airbus-Allee 1, D-28199 Bremen, Germany.
| | - Hergen Oltmann
- Airbus Defence and Space GmbH, Airbus-Allee 1, D-28199 Bremen, Germany.
| | - Stefan Feldmann
- Airbus Defence and Space GmbH, Airbus-Allee 1, D-28199 Bremen, Germany.
| | - Manfred Infanger
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Daniela Grimm
- Clinic for Plastic, Aesthetic and Hand Surgery, Otto von Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
- Department of Biomedicine, Aarhus University, Wilhelm Meyers Allé 4, DK-8000 Aarhus C, Denmark.
- Gravitational Biology and Translational Regenerative Medicine, Faculty of Medicine and Mechanical Engineering, Otto-von-Guericke-University Magdeburg, D-39120 Magdeburg, Germany.
| |
Collapse
|
16
|
Robinson M, Schor S, Barouch-Bentov R, Einav S. Viral journeys on the intracellular highways. Cell Mol Life Sci 2018; 75:3693-3714. [PMID: 30043139 PMCID: PMC6151136 DOI: 10.1007/s00018-018-2882-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/01/2018] [Accepted: 07/19/2018] [Indexed: 12/24/2022]
Abstract
Viruses are obligate intracellular pathogens that are dependent on cellular machineries for their replication. Recent technological breakthroughs have facilitated reliable identification of host factors required for viral infections and better characterization of the virus-host interplay. While these studies have revealed cellular machineries that are uniquely required by individual viruses, accumulating data also indicate the presence of broadly required mechanisms. Among these overlapping cellular functions are components of intracellular membrane trafficking pathways. Here, we review recent discoveries focused on how viruses exploit intracellular membrane trafficking pathways to promote various stages of their life cycle, with an emphasis on cellular factors that are usurped by a broad range of viruses. We describe broadly required components of the endocytic and secretory pathways, the Endosomal Sorting Complexes Required for Transport pathway, and the autophagy pathway. Identification of such overlapping host functions offers new opportunities to develop broad-spectrum host-targeted antiviral strategies.
Collapse
Affiliation(s)
- Makeda Robinson
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Stanford Schor
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
| | - Rina Barouch-Bentov
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
| | - Shirit Einav
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA.
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
| |
Collapse
|
17
|
Kamiyama H, Izumida M, Umemura Y, Hayashi H, Matsuyama T, Kubo Y. Role of Ezrin Phosphorylation in HIV-1 Replication. Front Microbiol 2018; 9:1912. [PMID: 30210460 PMCID: PMC6119696 DOI: 10.3389/fmicb.2018.01912] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/30/2018] [Indexed: 11/15/2022] Open
Abstract
Host-cell expression of the ezrin protein is required for CXCR4 (X4)-tropic HIV-1 infection. Ezrin function is regulated by phosphorylation at threonine-567. This study investigates the role of ezrin phosphorylation in HIV-1 infection and virion release. We analyzed the effects of ezrin mutations involving substitution of threonine-567 by alanine (EZ-TA), a constitutively inactive mutant, or by aspartic acid (EZ-TD), which mimics phosphorylated threonine. We also investigated the effects of ezrin silencing on HIV-1 virion release using a specific siRNA. We observed that X4-tropic HIV-1 vector infection was inhibited by expression of the EZ-TA mutant but increased by expression of the EZ-TD mutant, suggesting that ezrin phosphorylation in target cells is required for efficient HIV-1 entry. Expression of a dominant-negative mutant of ezrin (EZ-N) and ezrin silencing in HIV-1 vector-producing cells significantly reduced the infectivity of released virions without affecting virion production. This result indicates that endogenous ezrin expression is required for virion infectivity. The EZ-TD but not the EZ-TA inhibited virion release from HIV-1 vector-producing cells. Taken together, these findings suggest that ezrin phosphorylation in target cells is required for efficient HIV-1 entry but inhibits virion release from HIV-1 vector-producing cells.
Collapse
Affiliation(s)
- Haruka Kamiyama
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.,Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Mai Izumida
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Yuria Umemura
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Hideki Hayashi
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Medical University Research Administrator (MEDURA), Nagasaki University School of Medicine, Nagasaki, Japan
| | - Toshifumi Matsuyama
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Department of Cancer Stem Cell Biology, Institute of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yoshinao Kubo
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.,Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| |
Collapse
|
18
|
Bonfim-Melo A, Ferreira ER, Florentino PTV, Mortara RA. Amastigote Synapse: The Tricks of Trypanosoma cruzi Extracellular Amastigotes. Front Microbiol 2018; 9:1341. [PMID: 30013522 PMCID: PMC6036244 DOI: 10.3389/fmicb.2018.01341] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 05/31/2018] [Indexed: 12/11/2022] Open
Abstract
To complete its life cycle within the mammalian host, Trypanosoma cruzi, the agent of Chagas’ disease, must enter cells. Trypomastigotes originating from the insect vector (metacyclic) or from infected cells (bloodstream/tissue culture-derived) are the classical infective forms of the parasite and enter mammalian cells in an actin-independent manner. By contrast, amastigotes originating from the premature rupture of infected cells or transformed from swimming trypomastigotes (designated extracellular amastigotes, EAs) require functional intact microfilaments to invade non-phagocytic host cells. Earlier work disclosed the key features of EA-HeLa cell interplay: actin-rich protrusions called ‘cups’ are formed at EA invasion sites on the host cell membrane that are also enriched in actin-binding proteins, integrins and extracellular matrix elements. In the past decades we described the participation of membrane components and secreted factors from EAs as well as the actin-regulating proteins of host cells involved in what we propose to be a phagocytic-like mechanism of parasite uptake. Thus, regarding this new perspective herein we present previously described EA-induced ‘cups’ as parasitic synapse since they can play a role beyond its architecture function. In this review, we focus on recent findings that shed light on the intricate interaction between extracellular amastigotes and non-phagocytic HeLa cells.
Collapse
Affiliation(s)
- Alexis Bonfim-Melo
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Eden R Ferreira
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Pilar T V Florentino
- DNA Repair Lab, Biomedical Sciences Institute II, Universidade de São Paulo, São Paulo, Brazil
| | - Renato A Mortara
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| |
Collapse
|
19
|
Mello SS, Valente LJ, Raj N, Seoane JA, Flowers BM, McClendon J, Bieging-Rolett KT, Lee J, Ivanochko D, Kozak MM, Chang DT, Longacre TA, Koong AC, Arrowsmith CH, Kim SK, Vogel H, Wood LD, Hruban RH, Curtis C, Attardi LD. A p53 Super-tumor Suppressor Reveals a Tumor Suppressive p53-Ptpn14-Yap Axis in Pancreatic Cancer. Cancer Cell 2017; 32:460-473.e6. [PMID: 29017057 PMCID: PMC5659188 DOI: 10.1016/j.ccell.2017.09.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/19/2017] [Accepted: 09/08/2017] [Indexed: 12/25/2022]
Abstract
The p53 transcription factor is a critical barrier to pancreatic cancer progression. To unravel mechanisms of p53-mediated tumor suppression, which have remained elusive, we analyzed pancreatic cancer development in mice expressing p53 transcriptional activation domain (TAD) mutants. Surprisingly, the p5353,54 TAD2 mutant behaves as a "super-tumor suppressor," with an enhanced capacity to both suppress pancreatic cancer and transactivate select p53 target genes, including Ptpn14. Ptpn14 encodes a negative regulator of the Yap oncoprotein and is necessary and sufficient for pancreatic cancer suppression, like p53. We show that p53 deficiency promotes Yap signaling and that PTPN14 and TP53 mutations are mutually exclusive in human cancers. These studies uncover a p53-Ptpn14-Yap pathway that is integral to p53-mediated tumor suppression.
Collapse
Affiliation(s)
- Stephano S Mello
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Liz J Valente
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nitin Raj
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jose A Seoane
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Brittany M Flowers
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jacob McClendon
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kathryn T Bieging-Rolett
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jonghyeob Lee
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Danton Ivanochko
- Princess Margaret Cancer Centre, Structural Genomics Consortium and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Margaret M Kozak
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daniel T Chang
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Teri A Longacre
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Albert C Koong
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Cheryl H Arrowsmith
- Princess Margaret Cancer Centre, Structural Genomics Consortium and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Seung K Kim
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Hannes Vogel
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura D Wood
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ralph H Hruban
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christina Curtis
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura D Attardi
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
| |
Collapse
|
20
|
Hiruma S, Kamasaki T, Otomo K, Nemoto T, Uehara R. Dynamics and function of ERM proteins during cytokinesis in human cells. FEBS Lett 2017; 591:3296-3309. [DOI: 10.1002/1873-3468.12844] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/31/2017] [Accepted: 09/01/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Shota Hiruma
- Graduate School of Life Science; Hokkaido University; Japan
| | | | - Kohei Otomo
- Research Institute for Electronic Science; Hokkaido University; Japan
| | - Tomomi Nemoto
- Research Institute for Electronic Science; Hokkaido University; Japan
| | - Ryota Uehara
- Graduate School of Life Science; Hokkaido University; Japan
- Creative Research Institution; Hokkaido University; Japan
| |
Collapse
|
21
|
Chang CH, Lee HH, Lee CH. Substrate properties modulate cell membrane roughness by way of actin filaments. Sci Rep 2017; 7:9068. [PMID: 28831175 PMCID: PMC5567215 DOI: 10.1038/s41598-017-09618-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 07/24/2017] [Indexed: 01/09/2023] Open
Abstract
Cell membrane roughness has been proposed as a sensitive feature to reflect cellular physiological conditions. In order to know whether membrane roughness is associated with the substrate properties, we employed the non-interferometric wide-field optical profilometry (NIWOP) technique to measure the membrane roughness of living mouse embryonic fibroblasts with different conditions of the culture substrate. By controlling the surface density of fibronectin (FN) coated on the substrate, we found that cells exhibited higher membrane roughness as the FN density increased in company with larger focal adhesion (FA) sizes. The examination of membrane roughness was also confirmed with atomic force microscopy. Using reagents altering actin or microtubule cytoskeletons, we provided evidence that the dynamics of actin filaments rather than that of microtubules plays a crucial role for the regulation of membrane roughness. By changing the substrate rigidity, we further demonstrated that the cells seeded on compliant gels exhibited significantly lower membrane roughness and smaller FAs than the cells on rigid substrate. Taken together, our data suggest that the magnitude of membrane roughness is modulated by way of actin dynamics in cells responding to substrate properties.
Collapse
Affiliation(s)
- Chao-Hung Chang
- Research Center for Applied Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Hsiao-Hui Lee
- Department of Life Sciences & Institute of Genome Sciences, National Yang-Ming University, Taipei, 11221, Taiwan.
| | - Chau-Hwang Lee
- Research Center for Applied Sciences, Academia Sinica, Taipei, 11529, Taiwan. .,Institute of Biophotonics, National Yang-Ming University, Taipei, 11221, Taiwan. .,Department of Physics, National Taiwan University, Taipei, 10617, Taiwan.
| |
Collapse
|
22
|
Yano T, Kanoh H, Tamura A, Tsukita S. Apical cytoskeletons and junctional complexes as a combined system in epithelial cell sheets. Ann N Y Acad Sci 2017; 1405:32-43. [DOI: 10.1111/nyas.13432] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/12/2017] [Accepted: 06/14/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Tomoki Yano
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine; Osaka University; Osaka Japan
| | - Hatsuho Kanoh
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine; Osaka University; Osaka Japan
- Graduate School of Biostudies; Kyoto University; Kyoto Japan
| | - Atsushi Tamura
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine; Osaka University; Osaka Japan
| | - Sachiko Tsukita
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine; Osaka University; Osaka Japan
| |
Collapse
|
23
|
Feng Q, Bonder EM, Engevik AC, Zhang L, Tyska MJ, Goldenring JR, Gao N. Disruption of Rab8a and Rab11a causes formation of basolateral microvilli in neonatal enteropathy. J Cell Sci 2017; 130:2491-2505. [PMID: 28596241 DOI: 10.1242/jcs.201897] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 06/01/2017] [Indexed: 12/15/2022] Open
Abstract
Misplaced formation of microvilli to basolateral domains and intracellular inclusions in enterocytes are pathognomonic features in congenital enteropathy associated with mutation of the apical plasma membrane receptor syntaxin 3 (STX3). Although the demonstrated binding of Myo5b to the Rab8a and Rab11a small GTPases in vitro implicates cytoskeleton-dependent membrane sorting, the mechanisms underlying the microvillar location defect remain unclear. By selective or combinatory disruption of Rab8a and Rab11a membrane traffic in vivo, we demonstrate that transport of distinct cargo to the apical brush border rely on either individual or both Rab regulators, whereas certain basolateral cargos are redundantly transported by both factors. Enterocyte-specific Rab8a and Rab11a double-knockout mouse neonates showed immediate postnatal lethality and more severe enteropathy than single knockouts, with extensive formation of microvilli along basolateral surfaces. Notably, following an inducible Rab11a deletion from neonatal enterocytes, basolateral microvilli were induced within 3 days. These data identify a potentially important and distinct mechanism for a characteristic microvillus defect exhibited by enterocytes of patients with neonatal enteropathy.
Collapse
Affiliation(s)
- Qiang Feng
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| | - Edward M Bonder
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| | - Amy C Engevik
- Department of Surgery, and Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Lanjing Zhang
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA.,Department of Pathology, University Medical Center of Princeton, Plainsboro, NJ 08536, USA.,Rutgers Cancer Institute of New Jersey, Rutgers University, Piscataway, NJ 08903, USA
| | - Matthew J Tyska
- Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - James R Goldenring
- Department of Surgery, and Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.,Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.,Nashville VA Medical Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Nan Gao
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA .,Rutgers Cancer Institute of New Jersey, Rutgers University, Piscataway, NJ 08903, USA
| |
Collapse
|
24
|
Disorazoles Block Group A Streptococcal Invasion into Epithelial Cells Via Interference with the Host Factor Ezrin. Cell Chem Biol 2017; 24:159-170. [DOI: 10.1016/j.chembiol.2016.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/07/2016] [Accepted: 12/15/2016] [Indexed: 12/22/2022]
|
25
|
Van de Velde S, De Groef L, Stalmans I, Moons L, Van Hove I. Towards axonal regeneration and neuroprotection in glaucoma: Rho kinase inhibitors as promising therapeutics. Prog Neurobiol 2015; 131:105-19. [PMID: 26093354 DOI: 10.1016/j.pneurobio.2015.06.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 11/27/2022]
Abstract
Due to a prolonged life expectancy worldwide, the incidence of age-related neurodegenerative disorders such as glaucoma is increasing. Glaucoma is the second cause of blindness, resulting from a slow and progressive loss of retinal ganglion cells (RGCs) and their axons. Up to now, intraocular pressure (IOP) reduction is the only treatment modality by which ophthalmologists attempt to control disease progression. However, not all patients benefit from this therapy, and the pathophysiology of glaucoma is not always associated with an elevated IOP. These limitations, together with the multifactorial etiology of glaucoma, urge the pressing medical need for novel and alternative treatment strategies. Such new therapies should focus on preventing or retarding RGC death, but also on repair of injured axons, to ultimately preserve or improve structural and functional connectivity. In this respect, Rho-associated coiled-coil forming protein kinase (ROCK) inhibitors hold a promising potential to become very prominent drugs for future glaucoma treatment. Their field of action in the eye does not seem to be restricted to IOP reduction by targeting the trabecular meshwork or improving filtration surgery outcome. Indeed, over the past years, important progress has been made in elucidating their ability to improve ocular blood flow, to prevent RGC death/increase RGC survival and to retard axonal degeneration or induce proper axonal regeneration. Within this review, we aim to highlight the currently known capacity of ROCK inhibition to promote neuroprotection and regeneration in several in vitro, ex vivo and in vivo experimental glaucoma models.
Collapse
Affiliation(s)
- Sarah Van de Velde
- Laboratory of Ophthalmology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Lies De Groef
- Neural Circuit Development and Regeneration Research Group, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| | - Ingeborg Stalmans
- Laboratory of Ophthalmology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Lieve Moons
- Neural Circuit Development and Regeneration Research Group, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium.
| | - Inge Van Hove
- Neural Circuit Development and Regeneration Research Group, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| |
Collapse
|
26
|
Adada MM, Canals D, Jeong N, Kelkar AD, Hernandez-Corbacho M, Pulkoski-Gross MJ, Donaldson JC, Hannun YA, Obeid LM. Intracellular sphingosine kinase 2-derived sphingosine-1-phosphate mediates epidermal growth factor-induced ezrin-radixin-moesin phosphorylation and cancer cell invasion. FASEB J 2015. [PMID: 26209696 DOI: 10.1096/fj.15-274340] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The bioactive sphingolipid sphingosine-1-phosphate (S1P) mediates cellular proliferation, mitogenesis, inflammation, and angiogenesis. These biologies are mediated through S1P binding to specific GPCRs [sphingosine-1-phosphate receptor (S1PR)1-5] and some other less well-characterized intracellular targets. Ezrin-radixin-moesin (ERM) proteins, a family of adaptor molecules linking the cortical actin cytoskeleton to the plasma membrane, are emerging as critical regulators of cancer invasion via regulation of cell morphology and motility. Recently, we identified S1P as an acute ERM activator (via phosphorylation) through its action on S1PR2. In this work, we dissect the mechanism of S1P generation downstream of epidermal growth factor (EGF) leading to ERM phosphorylation and cancer invasion. Using pharmacologic inhibitors, small interfering RNA technologies, and genetic approaches, we demonstrate that sphingosine kinase (SK)2, and not SK1, is essential and sufficient in EGF-mediated ERM phosphorylation in HeLa cells. In fact, knocking down SK2 decreased ERM activation 2.5-fold. Furthermore, we provide evidence that SK2 is necessary to mediate EGF-induced invasion. In addition, overexpressing SK2 causes a 2-fold increase in HeLa cell invasion. Surprisingly, and for the first time, we find that this event, although dependent on S1PR2 activation, does not generate and does not require extracellular S1P secretion, therefore introducing a potential novel model of autocrine/intracrine action of S1P that still involves its GPCRs. These results define new mechanistic insights for EGF-mediated invasion and novel actions of SK2, therefore setting the stage for novel targets in the treatment of growth factor-driven malignancies.
Collapse
Affiliation(s)
- Mohamad M Adada
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Daniel Canals
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Nara Jeong
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Ashwin D Kelkar
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Maria Hernandez-Corbacho
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Michael J Pulkoski-Gross
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Jane C Donaldson
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Yusuf A Hannun
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| | - Lina M Obeid
- *Department of Medicine and the Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA; and Northport Veterans Affairs Medical Center, North Port, New York, USA
| |
Collapse
|
27
|
Animal Models and "Omics" Technologies for Identification of Novel Biomarkers and Drug Targets to Prevent Heart Failure. BIOMED RESEARCH INTERNATIONAL 2015; 2015:212910. [PMID: 26236717 PMCID: PMC4508378 DOI: 10.1155/2015/212910] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/26/2014] [Indexed: 12/12/2022]
Abstract
It is now accepted that heart failure (HF) is a complex multifunctional disease rather than simply a hemodynamic dysfunction. Despite its complexity, stressed cardiomyocytes often follow conserved patterns of structural remodelling in order to adapt, survive, and regenerate. When cardiac adaptations cannot cope with mechanical, ischemic, and metabolic loads efficiently or become chronically activated, as, for example, after infection, then the ongoing structural remodelling and dedifferentiation often lead to compromised pump function and patient death. It is, therefore, of major importance to understand key events in the progression from a compensatory left ventricular (LV) systolic dysfunction to a decompensatory LV systolic dysfunction and HF. To achieve this, various animal models in combination with an “omics” toolbox can be used. These approaches will ultimately lead to the identification of an arsenal of biomarkers and therapeutic targets which have the potential to shape the medicine of the future.
Collapse
|
28
|
Multiple Functions of Glutamate Uptake via Meningococcal GltT-GltM L-Glutamate ABC Transporter in Neisseria meningitidis Internalization into Human Brain Microvascular Endothelial Cells. Infect Immun 2015; 83:3555-67. [PMID: 26099588 DOI: 10.1128/iai.00654-15] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 06/17/2015] [Indexed: 12/30/2022] Open
Abstract
We previously reported that Neisseria meningitidis internalization into human brain microvasocular endothelial cells (HBMEC) was triggered by the influx of extracellular L-glutamate via the GltT-GltM L-glutamate ABC transporter, but the underlying mechanism remained unclear. We found that the ΔgltT ΔgltM invasion defect in assay medium (AM) was alleviated in AM without 10% fetal bovine serum (FBS) [AM(-S)]. The alleviation disappeared again in AM(-S) supplemented with 500 μM glutamate. Glutamate uptake by the ΔgltT ΔgltM mutant was less efficient than that by the wild-type strain, but only upon HBMEC infection. We also observed that both GltT-GltM-dependent invasion and accumulation of ezrin, a key membrane-cytoskeleton linker, were more pronounced when N. meningitidis formed larger colonies on HBMEC under physiological glutamate conditions. These results suggested that GltT-GltM-dependent meningococcal internalization into HBMEC might be induced by the reduced environmental glutamate concentration upon infection. Furthermore, we found that the amount of glutathione within the ΔgltT ΔgltM mutant was much lower than that within the wild-type N. meningitidis strain only upon HBMEC infection and was correlated with intracellular survival. Considering that the L-glutamate obtained via GltT-GltM is utilized as a nutrient in host cells, l-glutamate uptake via GltT-GltM plays multiple roles in N. meningitidis internalization into HBMEC.
Collapse
|
29
|
Jayasena T, Poljak A, Braidy N, Smythe G, Raftery M, Hill M, Brodaty H, Trollor J, Kochan N, Sachdev P. Upregulation of glycolytic enzymes, mitochondrial dysfunction and increased cytotoxicity in glial cells treated with Alzheimer's disease plasma. PLoS One 2015; 10:e0116092. [PMID: 25785936 PMCID: PMC4364672 DOI: 10.1371/journal.pone.0116092] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 12/04/2014] [Indexed: 11/19/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder associated with increased oxidative stress and neuroinflammation. Markers of increased protein, lipid and nucleic acid oxidation and reduced activities of antioxidant enzymes have been reported in AD plasma. Amyloid plaques in the AD brain elicit a range of reactive inflammatory responses including complement activation and acute phase reactions, which may also be reflected in plasma. Previous studies have shown that human AD plasma may be cytotoxic to cultured cells. We investigated the effect of pooled plasma (n = 20 each) from healthy controls, individuals with amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) on cultured microglial cells. AD plasma and was found to significantly decrease cell viability and increase glycolytic flux in microglia compared to plasma from healthy controls. This effect was prevented by the heat inactivation of complement. Proteomic methods and isobaric tags (iTRAQ) found the expression level of complement and other acute phase proteins to be altered in MCI and AD plasma and an upregulation of key enzymes involved in the glycolysis pathway in cells exposed to AD plasma. Altered expression levels of acute phase reactants in AD plasma may alter the energy metabolism of glia.
Collapse
Affiliation(s)
- Tharusha Jayasena
- Bioanalytical Mass Spectrometry Facility, MW Analytical Centre, University of New South Wales, Sydney, Australia
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Anne Poljak
- Bioanalytical Mass Spectrometry Facility, MW Analytical Centre, University of New South Wales, Sydney, Australia
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
- * E-mail:
| | - Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - George Smythe
- Bioanalytical Mass Spectrometry Facility, MW Analytical Centre, University of New South Wales, Sydney, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Mark Raftery
- Bioanalytical Mass Spectrometry Facility, MW Analytical Centre, University of New South Wales, Sydney, Australia
| | - Mark Hill
- School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Henry Brodaty
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- Dementia Collaborative Research Centre, University of New South Wales, Sydney, Australia
| | - Julian Trollor
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, the Prince of Wales Hospital, Sydney, Australia
| | - Nicole Kochan
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, the Prince of Wales Hospital, Sydney, Australia
| | - Perminder Sachdev
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, the Prince of Wales Hospital, Sydney, Australia
| |
Collapse
|
30
|
Wu CY, Lin MW, Wu DC, Huang YB, Huang HT, Chen CL. The role of phosphoinositide-regulated actin reorganization in chemotaxis and cell migration. Br J Pharmacol 2014; 171:5541-54. [PMID: 25420930 DOI: 10.1111/bph.12777] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 04/15/2014] [Accepted: 05/07/2014] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Reorganization of the actin cytoskeleton is essential for cell motility and chemotaxis. Actin-binding proteins (ABPs) and membrane lipids, especially phosphoinositides PI(4,5)P2 and PI(3,4,5)P3 are involved in the regulation of this reorganization. At least 15 ABPs have been reported to interact with, or regulated by phosphoinositides (PIPs) whose synthesis is regulated by extracellular signals. Recent studies have uncovered several parallel intracellular signalling pathways that crosstalk in chemotaxing cells. Here, we review the roles of ABPs and phosphoinositides in chemotaxis and cell migration. LINKED ARTICLES This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24.
Collapse
Affiliation(s)
- C-Y Wu
- Department of Biological Science, National Sun Yat-sen University, Kaohsiung, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University and Academia Sinica, Kaohsiung, Taiwan
| | | | | | | | | | | |
Collapse
|
31
|
Hatta K, Guo J, Ludke A, Dhingra S, Singh K, Huang ML, Weisel RD, Li RK. Expression of CNPY2 in mouse tissues: quantification and localization. PLoS One 2014; 9:e111370. [PMID: 25393402 PMCID: PMC4230931 DOI: 10.1371/journal.pone.0111370] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 09/30/2014] [Indexed: 12/18/2022] Open
Abstract
Canopy FGF signaling regulator 2 (CNPY2) is a FGF21-modulated protein containing a saposin B-type domain. In vitro studies have shown CNPY2 is able to enhance neurite outgrowth in neurons and stabilize the expression of low density lipoprotein receptor in macrophages and hepatocytes. However, no in vivo data are available on the normal expression of CNPY2 and information is lacking on which cell types express this protein in tissues. To address this, the present study examined CNPY2 expression at the mRNA and protein levels. Quantitative PCR and ELISA examination of mouse tissues showed that CNPY2 varies between organs, with the highest expression in the heart, lung and liver. Immunohistochemistry detected CNPY2 in a variety of cell types including skeletal, cardiac and smooth muscle myocytes, endothelial cells and epithelial cells. CNPY2 was also detectable in mouse blood and human and mouse uteri. These data demonstrate CNPY2 is widely distributed in tissues and suggest the protein has biological functions that have yet to be identified. Using these new observations we discuss possible functions of the protein.
Collapse
Affiliation(s)
- Kota Hatta
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Jian Guo
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Ana Ludke
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Sanjiv Dhingra
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Kaustabh Singh
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Ming-Li Huang
- Department of Gynecology and Obstetrics, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Richard D. Weisel
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Ren-Ke Li
- Division of Cardiovascular Surgery, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
| |
Collapse
|
32
|
Song W, Liu C, Seeley-Fallen MK, Miller H, Ketchum C, Upadhyaya A. Actin-mediated feedback loops in B-cell receptor signaling. Immunol Rev 2014; 256:177-89. [PMID: 24117821 DOI: 10.1111/imr.12113] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Upon recognizing cognate antigen, B cells mobilize multiple cellular apparatuses to propagate an optimal response. Antigen binding is transduced into cytoplasmic signaling events through B-cell antigen receptor (BCR)-based signalosomes at the B-cell surface. BCR signalosomes are dynamic and transient and are subsequently endocytosed for antigen processing. The function of BCR signalosomes is one of the determining factors for the fate of B cells: clonal expansion, anergy, or apoptosis. Accumulating evidence underscores the importance of the actin cytoskeleton in B-cell activation. We have begun to appreciate the role of actin dynamics in regulating BCR-mediated tonic signaling and the formation of BCR signalosomes. Our recent studies reveal an additional function of the actin cytoskeleton in the downregulation of BCR signaling, consequently contributing to the generation and maintenance of B-cell self-tolerance. In this review, we discuss how actin remodels its organization and dynamics in close coordination with BCR signaling and how actin remodeling in turn amplifies the activation and subsequent downregulation process of BCR signaling, providing vital feedback for optimal BCR activation.
Collapse
Affiliation(s)
- Wenxia Song
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, MD, USA
| | | | | | | | | | | |
Collapse
|
33
|
Osteopontin is up-regulated in chronic hepatitis C and is associated with cellular permissiveness for hepatitis C virus replication. Clin Sci (Lond) 2014; 126:845-55. [PMID: 24438228 DOI: 10.1042/cs20130473] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OPN (osteopontin)) is a Hh (Hedgehog)-regulated cytokine that is up-regulated during chronic liver injury and directly promotes fibrosis. We have reported that Hh signalling enhances viral permissiveness and replication in HCV (hepatitis C virus)-infected cells. Hence we hypothesized that OPN directly promotes HCV replication, and that targeting OPN could be beneficial in HCV. In the present study, we compared the expression of OPN mRNA and protein in HCV (JFH1)-infected Huh7 and Huh7.5 cells, and evaluated whether modulating OPN levels using exogenous OPN ligands (up-regulate OPN) or OPN-specific RNA-aptamers (neutralize OPN) leads to changes in HCV expression. Sera and livers from patients with chronic HCV were analysed to determine whether OPN levels were associated with disease severity or response to therapy. Compared with Huh7 cells, Huh7.5 cells support higher levels of HCV replication (15-fold) and expressed significantly more OPN mRNA (30-fold) and protein. Treating Huh7 cells with OPN ligands led to a dose-related increase in HCV (15-fold) and OPN (8-fold) mRNA. Conversely, treating Huh7.5 cells with OPN-specific RNA aptamers inhibited HCV RNA and protein by >50% and repressed OPN mRNA to basal levels. Liver OPN expression was significantly higher (3-fold) in patients with advanced fibrosis. Serum OPN positively correlated with fibrosis-stage (P=0.009), but negatively correlated with ETBCR (end-of-treatment biochemical response), ETVR (end-of-treatment virological response), SBCR (sustained biochemical response) and SVR (sustained virological response) (P=0.007). The OPN fibrosis score (serum OPN and presence of fibrosis ≥F2) may be a predictor of SVR. In conclusion, OPN is up-regulated in the liver and serum of patients with chronic hepatitis C, and supports increased viral replication. OPN neutralization may be a novel therapeutic strategy in chronic hepatitis C.
Collapse
|
34
|
Zhou J, Feng Y, Tao K, Su Z, Yu X, Zheng J, Zhang L, Yang D. The expression and phosphorylation of ezrin and merlin in human pancreatic cancer. Int J Oncol 2014; 44:2059-67. [PMID: 24728215 DOI: 10.3892/ijo.2014.2381] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 03/21/2014] [Indexed: 11/06/2022] Open
Abstract
Pancreatic carcinoma is the most common pancreatic malignancy and is associated with a very poor prognosis. Therefore, new prognostic factors and new treatment strategies are clearly needed. In this study, we retrospectively studied the levels of phosphorylated ezrin in 19 patients with pancreatic carcinoma by immunohistochemical analysis and determined the correlation between protein expression, clinicopathological characteristics and prognosis in pancreatic adenocarcinoma. We also characterized the phenotype of the overexpression of wild-type and phosphorylated ezrin and merlin in human pancreatic cancer cell lines. A significant correlation between the levels of phosphorylated ezrin 353 and ezrin 567 and the stage of pancreatic cancer was observed. Moreover, Kaplan-Meier analysis revealed that patients with high levels of phosphorylated ezrin had a significantly poorer survival rate (P<0.05). In addition, the overexpression of wild-type merlin or ezrin inhibited cell proliferation, migration and adhesion. However, the overexpression of T567D ezrin, a mutant that mimics permanent phosphorylation, promoted the proliferation, adhesion and migration of the pancreatic adenocarcinoma cell line SW1990. The overexpression of S518D merlin inhibited the growth of SW1990 and did not affect migration or adhesion. These results suggest that the phosphorylation of ezrin may contribute to the progression of pancreatic carcinoma and that the level of phosphorylated ezrin may serve as an adverse prognostic factor for pancreatic carcinoma.
Collapse
Affiliation(s)
- Jiahua Zhou
- Department of General Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| | - Yongjiang Feng
- Department of General Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| | - Ketao Tao
- Department of General Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| | - Zhanhai Su
- Basic Medical Research Center, Qinghai University, Xining 810001, P.R. China
| | - Xiaojin Yu
- Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing 210009, P.R. China
| | - Jie Zheng
- Department of Pathology, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| | - Lihua Zhang
- Department of Surgical Pathology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| | - Detong Yang
- Department of General Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, P.R. China
| |
Collapse
|
35
|
Brimacombe CL, Wilson GK, Hübscher SG, McKeating JA, Farquhar MJ. A role for CD81 and hepatitis C virus in hepatoma mobility. Viruses 2014; 6:1454-72. [PMID: 24662676 PMCID: PMC3970161 DOI: 10.3390/v6031454] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 01/27/2014] [Accepted: 03/05/2014] [Indexed: 12/21/2022] Open
Abstract
Tetraspanins are a family of small proteins that interact with themselves, host transmembrane and cytosolic proteins to form tetraspanin enriched microdomains (TEMs) that regulate important cellular functions. Several tetraspanin family members are linked to tumorigenesis. Hepatocellular carcinoma (HCC) is an increasing global health burden, in part due to the increasing prevalence of hepatitis C virus (HCV) associated HCC. The tetraspanin CD81 is an essential receptor for HCV, however, its role in hepatoma biology is uncertain. We demonstrate that antibody engagement of CD81 promotes hepatoma spread, which is limited by HCV infection, in an actin-dependent manner and identify an essential role for the C-terminal interaction with Ezrin-Radixin-Moesin (ERM) proteins in this process. We show enhanced hepatoma migration and invasion following expression of CD81 and a reduction in invasive potential upon CD81 silencing. In addition, we reveal poorly differentiated HCC express significantly higher levels of CD81 compared to adjacent non-tumor tissue. In summary, these data support a role for CD81 in regulating hepatoma mobility and propose CD81 as a tumour promoter.
Collapse
Affiliation(s)
- Claire L Brimacombe
- Viral Hepatitis Research Group, Institute for Biomedical Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Garrick K Wilson
- Viral Hepatitis Research Group, Institute for Biomedical Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Stefan G Hübscher
- Centre for Liver Research and NIHR Birmingham Liver Biomedical Research Unit, Institute for Biomedical Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Jane A McKeating
- Viral Hepatitis Research Group, Institute for Biomedical Research, University of Birmingham, Birmingham B15 2TT, UK.
| | - Michelle J Farquhar
- Viral Hepatitis Research Group, Institute for Biomedical Research, University of Birmingham, Birmingham B15 2TT, UK.
| |
Collapse
|
36
|
Mitotic Spindle Asymmetry: A Wnt/PCP-Regulated Mechanism Generating Asymmetrical Division in Cortical Precursors. Cell Rep 2014; 6:400-14. [DOI: 10.1016/j.celrep.2013.12.026] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 11/21/2013] [Accepted: 12/14/2013] [Indexed: 11/20/2022] Open
|
37
|
Regulation of Son of sevenless by the membrane-actin linker protein ezrin. Proc Natl Acad Sci U S A 2013; 110:20587-92. [PMID: 24297905 DOI: 10.1073/pnas.1222078110] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Receptor tyrosine kinases participate in several signaling pathways through small G proteins such as Ras (rat sarcoma). An important component in the activation of these G proteins is Son of sevenless (SOS), which catalyzes the nucleotide exchange on Ras. For optimal activity, a second Ras molecule acts as an allosteric activator by binding to a second Ras-binding site within SOS. This allosteric Ras-binding site is blocked by autoinhibitory domains of SOS. We have reported recently that Ras activation also requires the actin-binding proteins ezrin, radixin, and moesin. Here we report the mechanism by which ezrin modulates SOS activity and thereby Ras activation. Active ezrin enhances Ras/MAPK signaling and interacts with both SOS and Ras in vivo and in vitro. Moreover, in vitro kinetic assays with recombinant proteins show that ezrin also is important for the activity of SOS itself. Ezrin interacts with GDP-Ras and with the Dbl homology (DH)/pleckstrin homology (PH) domains of SOS, bringing GDP-Ras to the proximity of the allosteric site of SOS. These actions of ezrin are antagonized by the neurofibromatosis type 2 tumor-suppressor protein merlin. We propose an additional essential step in SOS/Ras control that is relevant for human cancer as well as all physiological processes involving Ras.
Collapse
|
38
|
Singh V, Erb U, Zöller M. Cooperativity of CD44 and CD49d in leukemia cell homing, migration, and survival offers a means for therapeutic attack. THE JOURNAL OF IMMUNOLOGY 2013; 191:5304-16. [PMID: 24127558 DOI: 10.4049/jimmunol.1301543] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A CD44 blockade drives leukemic cells into differentiation and apoptosis by dislodging from the osteogenic niche. Because anti-CD49d also supports hematopoietic stem cell mobilization, we sought to determine the therapeutic efficacy of a joint CD49d/CD44 blockade. To unravel the underlying mechanism, the CD49d(-) EL4 lymphoma was transfected with CD49d or point-mutated CD49d, prohibiting phosphorylation and FAK binding; additionally, a CD44(-) Jurkat subline was transfected with murine CD44, CD44 with a point mutation in the ezrin binding site, or with cytoplasmic tail-truncated CD44. Parental and transfected EL4 and Jurkat cells were evaluated for adhesion, migration, and apoptosis susceptibility in vitro and in vivo. Ligand-binding and Ab-blocking studies revealed CD44-CD49d cooperation in vitro and in vivo in adhesion, migration, and apoptosis resistance. The cooperation depends on ligand-induced proximity such that both CD44 and CD49d get access to src, FAK, and paxillin and via lck to the MAPK pathway, with the latter also supporting antiapoptotic molecule liberation. Accordingly, synergisms were only seen in leukemia cells expressing wild-type CD44 and CD49d. Anti-CD44 together with anti-CD49d efficiently dislodged EL4-CD49d/Jurkat-CD44 in bone marrow and spleen. Dislodging was accompanied by increased apoptosis susceptibility that strengthened low-dose chemotherapy, the combined treatment most strongly interfering with metastatic settlement and being partly curative. Ab treatment also promoted NK and Ab-dependent cellular cytotoxicity activation, which affected leukemia cells independent of CD44/CD49d tail mutations. Thus, mostly owing to a blockade of joint signaling, anti-CD44 and anti-CD49d hamper leukemic cell settlement and break apoptosis resistance, which strongly supports low-dose chemotherapy.
Collapse
Affiliation(s)
- Vibuthi Singh
- Department of Tumor Cell Biology, University Hospital of Surgery, 69120 Heidelberg, Germany
| | | | | |
Collapse
|
39
|
Persson A, Lindberg OR, Kuhn HG. Radixin inhibition decreases adult neural progenitor cell migration and proliferation in vitro and in vivo. Front Cell Neurosci 2013; 7:161. [PMID: 24065889 PMCID: PMC3781578 DOI: 10.3389/fncel.2013.00161] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 09/03/2013] [Indexed: 11/13/2022] Open
Abstract
Neuronal progenitors capable of long distance migration are produced throughout life in the subventricular zone (SVZ). Migration from the SVZ is carried out along a well-defined pathway called the rostral migratory stream (RMS). Our recent finding of the specific expression of the cytoskeleton linker protein radixin in neuroblasts suggests a functional role for radixin in RMS migration. The ezrin-radixin-moesin (ERM) family of proteins is capable of regulating migration through interaction with the actin cytoskeleton and transmembrane proteins. The ERM proteins are differentially expressed in the RMS with radixin and moesin localized to neuroblasts, and ezrin expression confined to astrocytes of the glial tubes. Here, we inhibited radixin function using the quinocarmycin analog DX52-1 which resulted in reduced neuroblast migration in vitro, while glial migration remained unaltered. Furthermore, the morphology of neuroblasts was distorted resulting in a rounded shape with no or short polysialylated neural cell adhesion molecule positive processes. Intracerebroventricular infusion of the radixin inhibitor resulted in accumulation of neuroblasts in the anterior SVZ. Neuroblast chains were short and intermittently interrupted in the SVZ and considerably disorganized in the RMS. Moreover, we studied the proliferation activity in the RMS after radixin inhibition, since concentrated radixin expression has been demonstrated in the cleavage furrow of dividing cells, which indicates a role of radixin in cell division. Radixin inhibition decreased neuroblast proliferation, whereas the proliferation of other cells in the RMS was not affected. Our results demonstrate a significant role for radixin in neuroblast proliferation and migration.
Collapse
Affiliation(s)
- Asa Persson
- Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | | | | |
Collapse
|
40
|
Vesicular transport of progeny parvovirus particles through ER and Golgi regulates maturation and cytolysis. PLoS Pathog 2013; 9:e1003605. [PMID: 24068925 PMCID: PMC3777860 DOI: 10.1371/journal.ppat.1003605] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/24/2013] [Indexed: 01/30/2023] Open
Abstract
Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway. Previously, it was thought that non-enveloped lytic parvoviruses were released through a lytic burst of cells at the end of infection. However, recent work demonstrated that these small non-enveloped single-stranded DNA viruses are actively transported through vesicles from the nucleus, the site of replication and assembly, to the cell periphery. The current investigation demonstrates that progeny particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane (PM). ERM family proteins radixin and moesin appear to play an essential role in this cellular secretion pathway. While passing through ER and Golgi cisternae, PVs maturate through post-assembly modifications, which significantly increase the infectivity of progeny virions. Finally, the vesicular transport of parvoviral particles was shown to regulate virus-induced cytolysis, thereby accelerating the further release and spread of progeny virions. As rodent PVs are currently viewed as oncolytic agents for cancer virotherapy, it is important to further investigate the mechanism of PV egress — not only to improve the spreading of these agents through the tumor mass, but also to optimize the induction of an anti-tumor immune response upon virus — induced cytolysis.
Collapse
|
41
|
Pu J, Mao Y, Lei X, Yan Y, Lu X, Tian J, Yin X, Zhao G, Zhang B. FERM domain containing protein 7 interacts with the Rho GDP dissociation inhibitor and specifically activates Rac1 signaling. PLoS One 2013; 8:e73108. [PMID: 23967341 PMCID: PMC3742540 DOI: 10.1371/journal.pone.0073108] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 07/18/2013] [Indexed: 11/28/2022] Open
Abstract
The FERM domain containing protein 7 gene (FRMD7) associated with the X-linked disorder idiopathic congenital nystagmus (ICN) is involved in the regulation of neurite elongation during neuronal development. Members of the Rho family of small G-proteins (Rho GTPases) are key regulators of the actin cytoskeleton and are implicated in the control of neuronal morphology. The Rho GDP dissociation inhibitor alpha, RhoGDIα, the main regulator of Rho GTPases, can form a complex with the GDP-bound form of Rho GTPases and inhibit their activation. Here, we demonstrate that the full length of the mouse FRMD7, rather than the N-terminus or the C-terminus alone, directly interacts with RhoGDIα and specifically initiates Rac1 signaling in mouse neuroblastoma cell line (neuro-2a). Moreover, we show that wild-type human FRMD7 protein is able to activate Rac1 signaling by interacting with RhoGDIα and releasing Rac1 from Rac1-RhoGDIα complex. However, two missense mutations (c.781C>G and c.886G>C) of human FRMD7 proteins weaken the ability to interact with RhoGDIα and release less Rac1, that induce the activation of Rac1 to a lesser degree; while an additional mutant, c.1003C>T, which results in a C-terminal truncated protein, almost fails to interact with RhoGDIα and to activate Rac1 signaling. Collectively, these results suggest that FRMD7 interacts with one of the Rho GTPase regulators, RhoGDIα, and activates the Rho subfamily member Rac1, which regulates reorganization of actin filaments and controls neuronal outgrowth. We predict that human mutant FRMD7 thus influences Rac1 signaling activation, which can lead to abnormal neuronal outgrowth and cause the X-linked ICN.
Collapse
Affiliation(s)
- Jiali Pu
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yanfang Mao
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaoguang Lei
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yaping Yan
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaoxiong Lu
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jun Tian
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xinzhen Yin
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Guohua Zhao
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Baorong Zhang
- Department of Neurology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- * E-mail:
| |
Collapse
|
42
|
Haseleu J, Anlauf E, Blaess S, Endl E, Derouiche A. Studying subcellular detail in fixed astrocytes: dissociation of morphologically intact glial cells (DIMIGs). Front Cell Neurosci 2013; 7:54. [PMID: 23653590 PMCID: PMC3642499 DOI: 10.3389/fncel.2013.00054] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 04/11/2013] [Indexed: 01/28/2023] Open
Abstract
Studying the distribution of astrocytic antigens is particularly hard when they are localized in their fine, peripheral astrocyte processes (PAPs), since these processes often have a diameter comparable to vesicles and small organelles. The most appropriate technique is immunoelectron microscopy, which is, however, a time-consuming procedure. Even in high resolution light microscopy, antigen localization is difficult to detect due to the small dimensions of these processes, and overlay from antigen in surrounding non-glial cells. Yet, PAPs frequently display antigens related to motility and glia-synaptic interaction. Here, we describe the dissociation of morphologically intact glial cells (DIMIGs), permitting unambiguous antigen localization using epifluorescence microscopy. Astrocytes are dissociated from juvenile (p13-15) mouse cortex by applying papain treatment and cytospin centrifugation to attach the cells to a slide. The cells and their complete processes including the PAPs is thus projected in 2D. The entire procedure takes 2.5-3 h. We show by morphometry that the diameter of DIMIGs, including the PAPs is similar to that of astrocytes in situ. In contrast to cell culture, results derived from this procedure allow for direct conclusions relating to (1) the presence of an antigen in cortical astrocytes, (2) subcellular antigen distribution, in particular when localized in the PAPs. The detailed resolution is shown in an exemplary study of the organization of the astrocytic cytoskeleton components actin, ezrin, tubulin, and GFAP. The distribution of connexin 43 in relation to a single astrocyte's process tree is also investigated.
Collapse
Affiliation(s)
- Julia Haseleu
- Institute of Cellular Neurosciences, University of Bonn Bonn, Germany
| | | | | | | | | |
Collapse
|
43
|
Zou LB, Shi S, Zhang RJ, Wang TT, Tan YJ, Zhang D, Fei XY, Ding GL, Gao Q, Chen C, Hu XL, Huang HF, Sheng JZ. Aquaporin-1 plays a crucial role in estrogen-induced tubulogenesis of vascular endothelial cells. J Clin Endocrinol Metab 2013; 98:E672-82. [PMID: 23450058 DOI: 10.1210/jc.2012-4081] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
CONTEXT Aquaporin-1 (AQP1) has been proposed as a mediator of estrogen-induced angiogenesis in human breast cancer and endometrial cancer. Elucidation of the molecular mechanisms governing AQP1-mediated, estrogen-induced angiogenesis may contribute to an improved understanding of tumor development. OBJECTIVE Our objective was to identify the estrogen-response element (ERE) in the promoter of the Aqp1 gene and investigate the effects and mechanisms of AQP1 on estrogen-induced tubulogenesis of vascular endothelial cells. SETTING The study was conducted in a university hospital in eastern China. MAIN OUTCOME MEASURES Immunohistological, real-time PCR and Western blot analyses were used to determine the expression AQP1 mRNA and protein in vascular endothelial cells. Chromatin immunoprecipitation analyses and luciferase reporter assays identified ERE-like motif in the promoter of the Aqp1 gene. RESULTS Expression of AQP1 in blood vessels of human breast and endometrial carcinoma tissues were significantly higher than controls. Estradiol (E2) dose-dependently increased the expression levels of AQP1 mRNA and protein in human umbilical vein endothelial cells (HUVECs). A functional ERE-like motif was identified in the promoter of the Aqp1 gene. AQP1 colocalized with ezrin, a component of the ezrin/radixin/moesin protein complex, and, ezrin colocalized with filamentous actin in HUVECs. Knockdown of AQP1 or ezrin with specific small interfering RNA significantly attenuated the formation of transcytoplasmic filamentous actin stress fibers induced by E2 and inhibited E2-enhanced cell proliferation, migration, invasion, and tubule formation of HUVECs. CONCLUSIONS Estrogen induces AQP1 expression by activating ERE in the promoter of the Aqp1 gene, resulting in tubulogenesis of vascular endothelial cells. These results provide new insights into the molecular mechanisms underpinning the angiogenic effects of estrogen.
Collapse
Affiliation(s)
- Li-Bo Zou
- The Key Laboratory of Reproductive Genetics, Zhejiang University, Hangzhou 310058, China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Kobayashi Y, Harada A, Furuta B, Asou H, Kato U, Umeda M. The role of NADRIN, a Rho GTPase-activating protein, in the morphological differentiation of astrocytes. J Biochem 2013; 153:389-98. [DOI: 10.1093/jb/mvt005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
45
|
Wu M, Liu DY, Yuan XR, Liu Q, Jiang XJ, Yuan D, Huang J, Li XJ, Yang ZQ. The expression of moesin in astrocytoma: correlation with pathologic grade and poor clinical outcome. Med Oncol 2013; 30:372. [DOI: 10.1007/s12032-012-0372-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 09/13/2012] [Indexed: 10/27/2022]
|
46
|
Yotova I, Quan P, Gaba A, Leditznig N, Pateisky P, Kurz C, Tschugguel W. Raf-1 levels determine the migration rate of primary endometrial stromal cells of patients with endometriosis. J Cell Mol Med 2013; 16:2127-39. [PMID: 22225925 PMCID: PMC3822983 DOI: 10.1111/j.1582-4934.2011.01520.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Endometriosis is a disease characterized by the localization of endometrial tissue outside the uterine cavity. The differences observed in migration of human endometrial stromal cells (hESC) obtained from patients with endometriosis versus healthy controls were proposed to correlate with the abnormal activation of Raf-1/ROCKII signalling pathway. To evaluate the mechanism by which Raf-1 regulates cytoskeleton reorganization and motility, we used primary eutopic (Eu-, n = 16) and ectopic (Ec-, n = 8; isolated from ovarian cysts) hESC of patients with endometriosis and endometriosis-free controls (Co-hESC, n = 14). Raf-1 siRNA knockdown in Co- and Eu-hESC resulted in contraction and decreased migration versus siRNA controls. This phenotype was reversed following the re-expression of Raf-1 in these cells. Lowest Raf-1 levels in Ec-hESC were associated with hyperactivated ROCKII and ezrin/radixin/moesin (E/R/M), impaired migration and a contracted phenotype similar to Raf-1 knockdown in Co- and Eu-hESC. We further show that the mechanism by which Raf-1 mediates migration in hESC includes direct myosin light chain phosphatase (MYPT1) phosphorylation and regulation of the levels of E/R/M, paxillin, MYPT1 and myosin light chain (MLC) phosphorylation indirectly via the hyperactivation of ROCKII kinase. Furthermore, we suggest that in contrast to Co-and Eu-hESC, where the cellular Raf-1 levels regulate the rate of migration, the low cellular Raf-1 content in Ec-hESC, might ensure their restricted migration by preserving the contracted cellular phenotype. In conclusion, our findings suggest that cellular levels of Raf-1 adjust the threshold of hESC migration in endometriosis.
Collapse
Affiliation(s)
- Iveta Yotova
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | | | | |
Collapse
|
47
|
Kashimoto R, Yamanaka H, Kobayashi K, Okubo M, Yagi H, Mimura O, Noguchi K. Phosphorylation of ezrin/radixin/moesin (ERM) protein in spinal microglia following peripheral nerve injury and lysophosphatidic acid administration. Glia 2012; 61:338-48. [PMID: 23065679 DOI: 10.1002/glia.22436] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 09/18/2012] [Indexed: 11/09/2022]
Abstract
Peripheral nerve injury activates spinal glial cells, which may contribute to the development of pain behavioral hypersensitivity. There is growing evidence that activated microglia show dynamic changes in cell morphology; however, the molecular mechanisms that underlie the modification of the membrane and cytoskeleton of microglia are not known. Here, we investigated the phosphorylation of ezrin, radixin, and moesin (ERM) proteins in the spinal cord after peripheral nerve injury. ERM is known to function as membrane-cytoskeletal linkers and be localized at filopodia- and microvilli-like structures. ERM proteins must be phosphorylated at a specific C-terminal threonine residue to be in the active state. The nature of ERM proteins in the spinal cord of animals in a neuropathic pain model has not been investigated and characterized. In the present study, we observed an increase in the phosphorylated ERM in the spinal microglia following spared nerve injury. The intrathecal administration of lysophosphatidic acid induced the phosphorylation of ERM proteins in microglia along with the development of mechanical pain hypersensitivity. Intrathecal administration of ERM antisense locked nucleic acid suppressed nerve injury-induced tactile allodynia and decreased the phosphorylation of ERM, but not the Iba1 staining pattern, in spinal glial cells. These findings suggest that lysophosphatidic acid induced the phosphorylation of ERM proteins in spinal microglia and may be involved in the emergence of neuropathic pain. These findings may underlie the pathological mechanisms of nerve injury-induced neuropathic pain.
Collapse
Affiliation(s)
- Ryosuke Kashimoto
- Department of Ophthalmology, Hyogo College of Medicine, Nishinomiya, Japan
| | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
Osteocytes were the forgotten bone cell until the bone community could become convinced that these cells do serve an important role in bone function and maintenance. In this review we trace the history of osteocyte characterization and present some of the major observations that are leading to the conclusion that these cells are not passive placeholders residing in the bone matrix, but are indeed, major orchestrators of bone remodeling.
Collapse
Affiliation(s)
- Dayong Guo
- University of Missouri, Kansas City, MO, USA
| | | |
Collapse
|
49
|
Activation of ezrin/radixin/moesin mediates attractive growth cone guidance through regulation of growth cone actin and adhesion receptors. J Neurosci 2012; 32:282-96. [PMID: 22219290 DOI: 10.1523/jneurosci.4794-11.2012] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The development of a functioning neural network relies on responses of axonal growth cones to molecular guidance cues that are encountered en route to their target tissue. Nerve growth factor (NGF) and neurotrophin-3 serve as attractive cues for chick embryo sensory growth cones in vitro and in vivo, but little is known about the actin-binding proteins necessary to mediate this response. The evolutionarily conserved ezrin/radixin/moesin (ERM) family of proteins can tether actin filaments to the cell membrane when phosphorylated at a conserved threonine residue. Here we show that acute neurotrophin stimulation rapidly increases active phospho-ERM levels in chick sensory neuron growth cone filopodia, coincident with an increase in filopodial L1 and β-integrin. Disrupting ERM function with a dominant-negative construct (DN-ERM) results in smaller and less motile growth cones with disorganized actin filaments. Previously, we found that NGF treatment increases actin-depolymerizing factor (ADF)/cofilin activity and growth cone F-actin (Marsick et al., 2010). Here, we show this F-actin increase, as well as attractive turning to NGF, is blocked when ERM function is disrupted despite normal activation of ADF/cofilin. We further show that DN-ERM expression disrupts leading edge localization of active ADF/cofilin and free F-actin barbed ends. Moreover, filopodial phospho-ERM levels are increased by incorporation of active ADF/cofilin and reduced by knockdown of L1CAM.Together, these data suggest that ERM proteins organize actin filaments in sensory neuron growth cones and are crucial for neurotrophin-induced remodeling of F-actin and redistribution of adhesion receptors.
Collapse
|
50
|
Canals D, Roddy P, Hannun YA. Protein phosphatase 1α mediates ceramide-induced ERM protein dephosphorylation: a novel mechanism independent of phosphatidylinositol 4, 5-biphosphate (PIP2) and myosin/ERM phosphatase. J Biol Chem 2012; 287:10145-10155. [PMID: 22311981 DOI: 10.1074/jbc.m111.306456] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
ERM (ezrin, radixin, and moesin) proteins are cytoskeletal interacting proteins that bind cortical actin, the plasma membrane, and membrane proteins, which are found in specialized plasma membrane structures such as microvilli and filopodia. ERM proteins are regulated by phosphatidylinositol 4, 5-biphosphate (PIP(2)) and by phosphorylation of a C-terminal threonine, and its inactivation involves PIP(2) hydrolysis and/or myosin phosphatase (MP). Recently, we demonstrated that ERM proteins are also subject to counter regulation by the bioactive sphingolipids ceramide and sphingosine 1-phosphate. Plasma membrane ceramide induces ERM dephosphorylation whereas sphingosine 1-phosphate induces their phosphorylation. In this work, we pursue the mechanisms by which ceramide regulates dephosphorylation. We found that this dephosphorylation was independent of hydrolysis and localization of PIP(2) and MP. However, the results show that ERM dephosphorylation was blocked by treatment with protein phosphatase 1 (PP1) pharmacological inhibitors and specifically by siRNA to PP1α, whereas okadaic acid, a PP2A inhibitor, failed. Moreover, a catalytic inactive mutant of PP1α acted as dominant negative of the endogenous PP1α. Additional results showed that the ceramide mechanism of PP1α activation is largely independent of PIP(2) hydrolysis and MP. Taken together, these results demonstrate a novel, acute mechanism of ERM regulation dependent on PP1α and plasma membrane ceramide.
Collapse
Affiliation(s)
- Daniel Canals
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Patrick Roddy
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Yusuf A Hannun
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425.
| |
Collapse
|