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Zhen H, Huang M, Zheng M, Gao L, Guo Z, Pang Q, Jin G, Zhou Z. WTAP regulates stem cells via TRAF6 to maintain planarian homeostasis and regeneration. Int J Biol Macromol 2023:124932. [PMID: 37268082 DOI: 10.1016/j.ijbiomac.2023.124932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 04/23/2023] [Accepted: 05/06/2023] [Indexed: 06/04/2023]
Abstract
WTAP, a highly conserved Wilms' tumor 1 interacting protein, is involved in a variety of biological processes. However, functional studies of WTAP in planarians have not been reported. In this study, we examined the spatiotemporal expression pattern of planarian DjWTAP and investigated its functions in planarians regeneration and homeostasis. Knocking-down DjWTAP resulted in severe morphological defects leading to lethality within 20 days. Silencing DjWTAP promoted the proliferation of PiwiA+ cells but impaired the lineage differentiation of epidermal, neural, digestive, and excretory cell types, suggesting a critical role for DjWTAP in stem cell self-renewal and differentiation in planarian. To further investigate the mechanisms underlying the defective differentiation, RNA-seq was employed to determine the transcriptomic alterations upon DjWTAP RNA interference. Histone 4 (H4), Histone-lysine N-methyltransferase-SETMAR like, and TNF receptor-associated factor 6 (TRAF6), were significantly upregulated in response to DjWTAP RNAi. Knocking-down TRAF6 largely rescued the defective tissue homeostasis and regeneration resulted from DjWTAP knockdown in planarians, suggesting that DjWTAP maintains planarian regeneration and homeostasis via TRAF6.
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Affiliation(s)
- Hui Zhen
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Mujie Huang
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Mingyue Zheng
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Lili Gao
- Laboratory of Developmental and Evolutionary Biology, Shandong University of Technology, Zibo, China
| | - Zepeng Guo
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Qiuxiang Pang
- Laboratory of Developmental and Evolutionary Biology, Shandong University of Technology, Zibo, China.
| | - Guoxiang Jin
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China; Guangdong Provincial Geriatrics Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, China.
| | - Zhongjun Zhou
- Guangdong Cardiovascular Institute, Medical Research Center, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China; School of Biomedical Sciences, The University of Hong Kong, Hong Kong; Reproductive Medicine Center, The University of Hong Kong-Shenzhen Hospital, Shenzhen, CHINA.
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2
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del Olmo I, Verdes A, Álvarez‐Campos P. Distinct patterns of gene expression during regeneration and asexual reproduction in the annelid Pristina leidyi. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2022; 338:405-420. [PMID: 35604322 PMCID: PMC9790225 DOI: 10.1002/jez.b.23143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 04/03/2022] [Accepted: 05/04/2022] [Indexed: 12/30/2022]
Abstract
Regeneration, the ability to replace lost body parts, is a widespread phenomenon in the animal kingdom often connected to asexual reproduction or fission, since the only difference between the two appears to be the stimulus that triggers them. Both developmental processes have largely been characterized; however, the molecular toolkit and genetic mechanisms underlying these events remain poorly unexplored. Annelids, in particular the oligochaete Pristina leidyi, provide a good model system to investigate these processes as they show diverse ways to regenerate, and can reproduce asexually through fission under laboratory conditions. Here, we used a comparative transcriptomics approach based on RNA-sequencing and differential gene expression analyses to understand the molecular mechanisms involved in anterior regeneration and asexual reproduction. We found 291 genes upregulated during anterior regeneration, including several regeneration-related genes previously reported in other annelids such as frizzled, paics, and vdra. On the other hand, during asexual reproduction, 130 genes were found upregulated, and unexpectedly, many of them were related to germline development during sexual reproduction. We also found important differences between anterior regeneration and asexual reproduction, with the latter showing a gene expression profile more similar to that of control individuals. Nevertheless, we identified 35 genes that were upregulated in both conditions, many of them related to cell pluripotency, stem cells, and cell proliferation. Overall, our results shed light on the molecular mechanisms that control anterior regeneration and asexual reproduction in annelids and reveal similarities with other animals, suggesting that the genetic machinery controlling these processes is conserved across metazoans.
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Affiliation(s)
- Irene del Olmo
- Department of Biology (Zoology)Universidad Autónoma de MadridMadridSpain
| | - Aida Verdes
- Department of Biodiversity and Evolutionary BiologyMuseo Nacional de Ciencias Naturales de MadridMadridSpain
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3
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Allen JM, Balagtas M, Barajas E, Cano Macip C, Alvarez Zepeda S, Iberkleid I, Duncan EM, Zayas RM. RNAi Screen of RING/U-Box Domain Ubiquitin Ligases Identifies Critical Regulators of Tissue Regeneration in Planarians. Front Cell Dev Biol 2022; 9:803419. [PMID: 35127720 PMCID: PMC8807557 DOI: 10.3389/fcell.2021.803419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 12/20/2021] [Indexed: 11/30/2022] Open
Abstract
Regenerative processes depend on the interpretation of signals to coordinate cell behaviors. The role of ubiquitin-mediated signaling is known to be important in many cellular and biological contexts, but its role in regeneration is not well understood. To investigate how ubiquitylation impacts tissue regeneration in vivo, we are studying planarians that are capable of regenerating after nearly any injury using a population of stem cells. Here we used RNAi to screen RING/U-box E3 ubiquitin ligases that are highly expressed in planarian stem cells and stem cell progeny. RNAi screening identified nine genes with functions in regeneration, including the spliceosomal factor prpf19 and histone modifier rnf2; based on their known roles in developmental processes, we further investigated these two genes. We found that prpf19 was required for animal survival but not for stem cell maintenance, suggesting a role in promoting cell differentiation. Because RNF2 is the catalytic subunit of the Polycomb Repressive Complex 1 (PRC1), we also examined other putative members of this complex (CBX and PHC). We observed a striking phenotype of regional tissue misspecification in cbx and phc RNAi planarians. To identify genes regulated by PRC1, we performed RNA-seq after knocking down rnf2 or phc. Although these proteins are predicted to function in the same complex, we found that the set of genes differentially expressed in rnf2 versus phc RNAi were largely non-overlapping. Using in situ hybridization, we showed that rnf2 regulates gene expression levels within a tissue type, whereas phc is necessary for the spatial restriction of gene expression, findings consistent with their respective in vivo phenotypes. This work not only uncovered roles for RING/U-box E3 ligases in stem cell regulation and regeneration, but also identified differential gene targets for two putative PRC1 factors required for maintaining cell-type-specific gene expression in planarians.
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Affiliation(s)
- John M Allen
- Department of Biology, San Diego State University, San Diego, CA, United States
- Deparment of Biology, University of Kentucky, Lexington, KY, United States
| | - Madison Balagtas
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Elizabeth Barajas
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Carolina Cano Macip
- Department of Biology, San Diego State University, San Diego, CA, United States
| | | | - Ionit Iberkleid
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Elizabeth M Duncan
- Deparment of Biology, University of Kentucky, Lexington, KY, United States
| | - Ricardo M Zayas
- Department of Biology, San Diego State University, San Diego, CA, United States
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Zhu J, Wu Y, Lao S, Shen J, Yu Y, Fang C, Zhang N, Li Y, Zhang R. Targeting TRIM54/Axin1/β-Catenin Axis Prohibits Proliferation and Metastasis in Hepatocellular Carcinoma. Front Oncol 2021; 11:759842. [PMID: 34956880 PMCID: PMC8695909 DOI: 10.3389/fonc.2021.759842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/15/2021] [Indexed: 11/15/2022] Open
Abstract
Accumulating evidence demonstrates that dysregulation of ubiquitin-mediated degradation of oncogene or suppressors plays an important role in several diseases. However, the function and molecular mechanisms of ubiquitin ligases underlying hepatocellular carcinoma (HCC) remain elusive. In the current study, we show that overexpression of TRIM54 was associated with HCC progression. TRIM54 overexpression facilitates proliferation and lung metastasis; however, inhibition of TRIM54 significantly suppressed HCC progression both in vitro and in vivo. Mechanically, we demonstrated that TRIM54 directly interacts with Axis inhibition proteins 1 (Axin1) and induces E3 ligase-dependent proteasomal turnover of Axin1 and substantially induces sustained activation of wnt/β-catenin in HCC cell lines. Furthermore, we showed that inhibition of the wnt/β-catenin signaling pathway via small molecule inhibitors significantly suppressed TRIM54-induced proliferation. Our data suggest that TRIM54 might function as an oncogenic gene and targeting the TRIM54/Axin1/β-catenin axis signaling may be a promising prognostic factor and a valuable therapeutic target for HCC.
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Affiliation(s)
- Jinrong Zhu
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Yongqi Wu
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shaoxi Lao
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jianfei Shen
- Department of Cardiothoracic Surgery, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Yijian Yu
- Department of Cardiothoracic Surgery, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Chunqiang Fang
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Na Zhang
- Department of General Practice, Heyuan People's Hospital, Heyuan, Guangdong, China
| | - Yan Li
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Rongxin Zhang
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Life Sciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
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Tian Q, Sun Y, Gao T, Li J, Fang H, Zhang S. Djnedd4L Is Required for Head Regeneration by Regulating Stem Cell Maintenance in Planarians. Int J Mol Sci 2021; 22:ijms222111707. [PMID: 34769140 PMCID: PMC8583885 DOI: 10.3390/ijms222111707] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 12/02/2022] Open
Abstract
SUMOylation and ubiquitylation are homologous processes catalyzed by homologous enzymes, and they are involved in nearly all aspects of eukaryotic biology. Planarians, which have the remarkable ability to regenerate their central nervous system (CNS), provide an excellent opportunity to investigate the molecular processes of CNS regeneration in vivo. In this study, we analyzed gene expression profiles during head regeneration with an RNA-seq-based screening approach and found that Djnedd4L and Djubc9 were required for head regeneration in planarians. RNA interference targeting of Djubc9 caused the phospho-H3 mitotic cells to decrease in quantity, or even become absent as a part of the Djubc9 RNAi phenotype, which also showed the collapse of the stem cell lineage along with the reduced expression of epidermal differentiation markers. Furthermore, we found that Djnedd4L RNAi induced increased cell division and promoted the premature differentiation during regeneration. Taken together, our findings show that Djubc9 and Djnedd4L are required for stem cell maintenance in the planarian Dugesia japonica, which helps to elucidate the role of SUMOylation and ubiquitylation in regulating the regeneration process.
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Affiliation(s)
- Qingnan Tian
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
| | - Yujia Sun
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
| | - Tingting Gao
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
| | - Jiaxin Li
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
| | - Huimin Fang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
- Correspondence: (H.F.); (S.Z.)
| | - Shoutao Zhang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; (Q.T.); (Y.S.); (T.G.); (J.L.)
- Henan Key Laboratory of Bioactive Macromolecules, Zhengzhou 450001, China
- Correspondence: (H.F.); (S.Z.)
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Molina MD, Cebrià F. Decoding Stem Cells: An Overview on Planarian Stem Cell Heterogeneity and Lineage Progression. Biomolecules 2021; 11:1532. [PMID: 34680165 PMCID: PMC8533874 DOI: 10.3390/biom11101532] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/11/2021] [Accepted: 10/12/2021] [Indexed: 01/26/2023] Open
Abstract
Planarians are flatworms capable of whole-body regeneration, able to regrow any missing body part after injury or amputation. The extraordinary regenerative capacity of planarians is based upon the presence in the adult of a large population of somatic pluripotent stem cells. These cells, called neoblasts, offer a unique system to study the process of stem cell specification and differentiation in vivo. In recent years, FACS-based isolation of neoblasts, RNAi functional analyses as well as high-throughput approaches such as single-cell sequencing have allowed a rapid progress in our understanding of many different aspects of neoblast biology. Here, we summarize our current knowledge on the molecular signatures that define planarian neoblasts heterogeneity, which includes a percentage of truly pluripotent stem cells, and guide the commitment of pluripotent neoblasts into lineage-specific progenitor cells, as well as their differentiation into specific planarian cell types.
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Affiliation(s)
- M. Dolores Molina
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), 08028 Barcelona, Spain
| | - Francesc Cebrià
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), 08028 Barcelona, Spain
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Collagen IV differentially regulates planarian stem cell potency and lineage progression. Proc Natl Acad Sci U S A 2021; 118:2021251118. [PMID: 33859045 PMCID: PMC8072372 DOI: 10.1073/pnas.2021251118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Comprehensive assessment of matrisome genes identified collagen IV as one of the many extracellular matrix (ECM) proteins regulating the stem cell pool in planarian tissue homeostasis and regeneration. While collagen IV has been shown to be involved in stem cell biology, our finding links it to pluripotent stem cells in vivo, including self-renewal and differentiation into tissue-specific progenitors. We show a link between the ECM niches in the parenchyma/gut region and EGF/neuregulin-secreting neurons, thus providing mechanistic insight into interactions between cell niches. The conservation of basement membranes between planarian and mammalian gut niches suggests a similar interplay may exist in the mammalian systems, worthy of further investigation. The extracellular matrix (ECM) provides a precise physical and molecular environment for cell maintenance, self-renewal, and differentiation in the stem cell niche. However, the nature and organization of the ECM niche is not well understood. The adult freshwater planarian Schmidtea mediterranea maintains a large population of multipotent stem cells (neoblasts), presenting an ideal model to study the role of the ECM niche in stem cell regulation. Here we tested the function of 165 planarian homologs of ECM and ECM-related genes in neoblast regulation. We identified the collagen gene family as one with differential effects in promoting or suppressing proliferation of neoblasts. col4-1, encoding a type IV collagen α-chain, had the strongest effect. RNA interference (RNAi) of col4-1 impaired tissue maintenance and regeneration, causing tissue regression. Finally, we provide evidence for an interaction between type IV collagen, the discoidin domain receptor, and neuregulin-7 (NRG-7), which constitutes a mechanism to regulate the balance of symmetric and asymmetric division of neoblasts via the NRG-7/EGFR pathway.
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Fraguas S, Cárcel S, Vivancos C, Molina MD, Ginés J, Mazariegos J, Sekaran T, Bartscherer K, Romero R, Cebrià F. CREB-binding protein (CBP) gene family regulates planarian survival and stem cell differentiation. Dev Biol 2021; 476:53-67. [PMID: 33774010 DOI: 10.1016/j.ydbio.2021.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 12/21/2022]
Abstract
In developmental biology, the regulation of stem cell plasticity and differentiation remains an open question. CBP(CREB-binding protein)/p300 is a conserved gene family that functions as a transcriptional co-activator and plays important roles in a wide range of cellular processes, including cell death, the DNA damage response, and tumorigenesis. The acetyl transferase activity of CBPs is particularly important, as histone and non-histone acetylation results in changes in chromatin architecture and protein activity that affect gene expression. Many studies have described the conserved functions of CBP/p300 in stem cell proliferation and differentiation. The planarian Schmidtea mediterranea is an excellent model for the in vivo study of the molecular mechanisms underlying stem cell differentiation during regeneration. However, how this process is regulated genetically and epigenetically is not well-understood yet. We identified 5 distinct Smed-cbp genes in S. mediterranea that show different expression patterns. Functional analyses revealed that Smed-cbp-2 appears to be essential for stem cell maintenance. On the other hand, the silencing of Smed-cbp-3 resulted in the growth of blastemas that were apparently normal, but remained largely unpigmented and undifferentiated. Smed-cbp-3 silencing also affected the differentiation of several cell lineages including neural, epidermal, digestive, and excretory cell types. Finally, we analysed the predicted interactomes of CBP-2 and CBP-3 as an initial step to better understand their functions in planarian stem cell biology. Our results indicate that planarian cbp genes play key roles in stem cell maintenance and differentiation.
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Affiliation(s)
- Susanna Fraguas
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain; Institute of Biomedicine of the University of Barcelona (IBUB), Spain
| | - Sheila Cárcel
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain
| | - Coral Vivancos
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain
| | - Ma Dolores Molina
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain; Institute of Biomedicine of the University of Barcelona (IBUB), Spain
| | - Jordi Ginés
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain
| | - Judith Mazariegos
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain
| | | | | | - Rafael Romero
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain
| | - Francesc Cebrià
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain; Institute of Biomedicine of the University of Barcelona (IBUB), Spain.
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Stelman CR, Smith BM, Chandra B, Roberts-Galbraith RH. CBP/p300 homologs CBP2 and CBP3 play distinct roles in planarian stem cell function. Dev Biol 2021; 473:130-143. [PMID: 33607113 DOI: 10.1016/j.ydbio.2021.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 11/19/2022]
Abstract
Chromatin modifications function as critical regulators of gene expression and cellular identity, especially in the regulation and maintenance of the pluripotent state. However, many studies of chromatin modification in stem cells-and pluripotent stem cells in particular-are performed in mammalian stem cell culture, an in vitro condition mimicking a very transient state during mammalian development. Thus, new models for studying pluripotent stem cells in vivo could be helpful for understanding the roles of chromatin modification, for confirming prior in vitro studies, and for exploring evolution of the pluripotent state. The freshwater flatworm, Schmidtea mediterranea, is an excellent model for studying adult pluripotent stem cells, particularly in the context of robust, whole-body regeneration. To identify chromatin modifying and remodeling enzymes critical for planarian regeneration and stem cell maintenance, we took a candidate approach and screened planarian homologs of 25 genes known to regulate chromatin biology in other organisms. Through our study, we identified six genes with novel functions in planarian homeostasis, regeneration, and behavior. Of the list of genes characterized, we identified five planarian homologs of the mammalian CREB-Binding Protein (CBP) and p300 family of histone acetyltransferases, representing an expansion of this family in planarians. We find that two planarian CBP family members are required for planarian survival, with knockdown of Smed-CBP2 and Smed-CBP3 causing distinct defects in stem cell maintenance or function. Loss of CBP2 causes a quick, dramatic loss of stem cells, while knockdown of CBP3 affects stem cells more narrowly, influencing differentiation of several cell types that include neuronal subtypes and cells of the eye. Further, we find that Smed-CBP1 is required for planarian fissioning behavior. We propose that the division of labor among a diversified CBP family in planarians presents an opportunity to dissect specific functions of a broadly important histone acetyltransferase family.
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Affiliation(s)
- Clara R Stelman
- Department of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Britessia M Smith
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Bidushi Chandra
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Rachel H Roberts-Galbraith
- Department of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Cellular Biology, University of Georgia, Athens, GA, USA.
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Tubgcp3 is a mitotic regulator of planarian epidermal differentiation. Gene 2021; 775:145440. [PMID: 33482282 DOI: 10.1016/j.gene.2021.145440] [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: 02/15/2020] [Revised: 09/29/2020] [Accepted: 01/13/2021] [Indexed: 11/20/2022]
Abstract
Tubgcp3/GCP3 (The centrosomal protein γ-tubulin complex protein 3) is a component of the γ-tubulin small complexes (γ-TuSCs) and γ-tubulin ring complexes (γ-TuRCs), which play critical roles in mitotic spindle formation during mitosis. However, its function in stem cell development has not been thoroughly elucidated. The planarian flatworm, which contains a large number of adult somatic stem cells (neoblasts), is a unique model to study stem cell lineage development in vivo. Here, we identified a homolog of Tubgcp3 in planarian Dugesia japonica, and found that Tubgcp3 is required for the maintenance of epidermal lineage. RNAi targeting Tubgcp3 resulted in tissue homeostasis and regeneration defect. Knockdown of Tubgcp3 reduced cell divisions and led to a loss of the mature epidermal cells. Our findings indicate that Tubgcp3 is a mitotic regulator and plays a crucial role in planarian epidermal differentiation.
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Brunet M, Vargas C, Larrieu D, Torrisani J, Dufresne M. E3 Ubiquitin Ligase TRIP12: Regulation, Structure, and Physiopathological Functions. Int J Mol Sci 2020; 21:ijms21228515. [PMID: 33198194 PMCID: PMC7697007 DOI: 10.3390/ijms21228515] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 02/06/2023] Open
Abstract
The Thyroid hormone Receptor Interacting Protein 12 (TRIP12) protein belongs to the 28-member Homologous to the E6-AP C-Terminus (HECT) E3 ubiquitin ligase family. First described as an interactor of the thyroid hormone receptor, TRIP12’s biological importance was revealed by the embryonic lethality of a murine model bearing an inactivating mutation in the TRIP12 gene. Further studies showed the participation of TRIP12 in the regulation of major biological processes such as cell cycle progression, DNA damage repair, chromatin remodeling, and cell differentiation by an ubiquitination-mediated degradation of key protein substrates. Moreover, alterations of TRIP12 expression have been reported in cancers that can serve as predictive markers of therapeutic response. The TRIP12 gene is also referenced as a causative gene associated to intellectual disorders such as Clark–Baraitser syndrome and is clearly implicated in Autism Spectrum Disorder. The aim of the review is to provide an exhaustive and integrated overview of the different aspects of TRIP12 ranging from its regulation, molecular functions and physio-pathological implications.
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Affiliation(s)
- Manon Brunet
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1037, Centre de Recherches en Cancérologie de Toulouse, CEDEX 1, 31 037 Toulouse, France; (M.B.); (C.V.); (D.L.)
- Université Toulouse III-Paul Sabatier, CEDEX 9, 31 062 Toulouse, France
| | - Claire Vargas
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1037, Centre de Recherches en Cancérologie de Toulouse, CEDEX 1, 31 037 Toulouse, France; (M.B.); (C.V.); (D.L.)
- Université Toulouse III-Paul Sabatier, CEDEX 9, 31 062 Toulouse, France
| | - Dorian Larrieu
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1037, Centre de Recherches en Cancérologie de Toulouse, CEDEX 1, 31 037 Toulouse, France; (M.B.); (C.V.); (D.L.)
- Université Toulouse III-Paul Sabatier, CEDEX 9, 31 062 Toulouse, France
| | - Jérôme Torrisani
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1037, Centre de Recherches en Cancérologie de Toulouse, CEDEX 1, 31 037 Toulouse, France; (M.B.); (C.V.); (D.L.)
- Université Toulouse III-Paul Sabatier, CEDEX 9, 31 062 Toulouse, France
- Correspondence: (J.T.); (M.D.); Tel.: +33-582-741-644 (J.T.); +33-582-741-643 (M.D.)
| | - Marlène Dufresne
- Institut National de la Santé et de la Recherche Médicale, INSERM Unit 1037, Centre de Recherches en Cancérologie de Toulouse, CEDEX 1, 31 037 Toulouse, France; (M.B.); (C.V.); (D.L.)
- Université Toulouse III-Paul Sabatier, CEDEX 9, 31 062 Toulouse, France
- Correspondence: (J.T.); (M.D.); Tel.: +33-582-741-644 (J.T.); +33-582-741-643 (M.D.)
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Forsthoefel DJ, Cejda NI, Khan UW, Newmark PA. Cell-type diversity and regionalized gene expression in the planarian intestine. eLife 2020; 9:e52613. [PMID: 32240093 PMCID: PMC7117911 DOI: 10.7554/elife.52613] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 03/06/2020] [Indexed: 12/17/2022] Open
Abstract
Proper function and repair of the digestive system are vital to most animals. Deciphering the mechanisms involved in these processes requires an atlas of gene expression and cell types. Here, we applied laser-capture microdissection (LCM) and RNA-seq to characterize the intestinal transcriptome of Schmidtea mediterranea, a planarian flatworm that can regenerate all organs, including the gut. We identified hundreds of genes with intestinal expression undetected by previous approaches. Systematic analyses revealed extensive conservation of digestive physiology and cell types with other animals, including humans. Furthermore, spatial LCM enabled us to uncover previously unappreciated regionalization of gene expression in the planarian intestine along the medio-lateral axis, especially among intestinal goblet cells. Finally, we identified two intestine-enriched transcription factors that specifically regulate regeneration (hedgehog signaling effector gli-1) or maintenance (RREB2) of goblet cells. Altogether, this work provides resources for further investigation of mechanisms involved in gastrointestinal function, repair and regeneration.
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Affiliation(s)
- David J Forsthoefel
- Genes and Human Disease Research Program, Oklahoma Medical Research FoundationOklahoma CityUnited States
- Howard Hughes Medical Institute, Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Nicholas I Cejda
- Genes and Human Disease Research Program, Oklahoma Medical Research FoundationOklahoma CityUnited States
| | - Umair W Khan
- Howard Hughes Medical Institute, Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Phillip A Newmark
- Howard Hughes Medical Institute, Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
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13
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de Dieuleveult M, Miotto B. Ubiquitin Dynamics in Stem Cell Biology: Current Challenges and Perspectives. Bioessays 2020; 42:e1900129. [PMID: 31967345 DOI: 10.1002/bies.201900129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 12/18/2019] [Indexed: 11/09/2022]
Abstract
Ubiquitination plays a central role in the regulation of stem cell self-renewal, propagation, and differentiation. In this review, the functions of ubiquitin dynamics in a myriad of cellular processes, acting along side the pluripotency network, to regulate embryonic stem cell identity are highlighted. The implication of deubiquitinases (DUBs) and E3 Ubiquitin (Ub) ligases in cellular functions beyond protein degradation is reported, including key functions in the regulation of mRNA stability, protein translation, and intra-cellular trafficking; and how it affects cell metabolism, the micro-environment, and chromatin organization is discussed. Finally, unsolved issues in the field are emphasized and will need to be tackled in order to fully understand the contribution of ubiquitin dynamics to stem cell self-renewal and differentiation.
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Affiliation(s)
- Maud de Dieuleveult
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, F-75014, Paris, France
| | - Benoit Miotto
- Université de Paris, Institut Cochin, INSERM, U1016, CNRS, UMR8104, F-75014, Paris, France
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14
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Li Y, Zhai L, Fan J, Ren J, Gong W, Wang X, Huang J. Genome-wide identification, phylogenetic and expression analysis of the maize HECT E3 ubiquitin ligase genes. Genetica 2019; 147:391-400. [PMID: 31741104 DOI: 10.1007/s10709-019-00080-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 11/13/2019] [Indexed: 11/27/2022]
Abstract
HECT (homologous to the E6AP carboxyl terminus) ubiquitin ligase genes (E3s) are enzymes with diverse functions influencing plant growth, development, and responses to abiotic stresses. However, there is relatively little information available regarding the maize HECT E3 gene family. In the present study, 12 maize HECT E3 genes (ZmUPL1 to ZmUPL12) were identified at the whole-genome level. The phylogenetic relationships, structures, and expression levels of the maize HECT E3 genes were then analyzed. On the basis of the constructed maximum likelihood phylogenetic tree, the HECT E3 genes were divided into six groups. The quantitative real-time polymerase chain reaction assay results revealed that all of the maize ZmUPL genes were expressed in most of the examined tissues and were responsive to three abiotic stresses. Considered together, the study results may provide a useful foundation for future investigations of maize stress-tolerance genes as well as functional analyses of the E3 enzymes in diverse agriculturally important crop species.
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Affiliation(s)
- Yunfeng Li
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Lihong Zhai
- Medical College, Hubei University of Arts and Science, Xiangyang, 441053, China
| | - Jingsheng Fan
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Jiaxin Ren
- Medical College, Hubei University of Arts and Science, Xiangyang, 441053, China
| | - Wenrong Gong
- Medical College, Hubei University of Arts and Science, Xiangyang, 441053, China
| | - Xin Wang
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Jun Huang
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China. .,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.
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15
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Yujia S, Tingting G, Jiaxin L, Saisai Z, Zhitai H, Qingnan T, Shoutao Z. Cdc42 regulate the apoptotic cell death required for planarian epidermal regeneration and homeostasis. Int J Biochem Cell Biol 2019; 112:107-113. [PMID: 31102665 DOI: 10.1016/j.biocel.2019.05.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 02/07/2023]
Abstract
Rho GTPases have been shown previously to play important roles in several cellular processes by regulating the organization of the actin and microtubule cytoskeletons. However, the mechanisms of Rho GTPases that integrate the cellular responses during regeneration have not been thoroughly elucidated. The planarian flatworm, which contains a large number of adult somatic stem cells (neoblasts), is a unique model to study stem cell lineage development in vivo. Here, we focus on cdc42, which is an extensively characterized member among Rho GTPases. We found that cdc42 is required for the maintenance of epidermal lineage. Cdc42 RNAi induced a sustained increased of cell death and led to a loss of the mature epidermal cells but without affected cell division. Our results indicate that cdc42 function as an inhibitor to block the excessive apoptotic cell death in planarian epidermal regeneration and homeostasis.
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Affiliation(s)
- Sun Yujia
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Gao Tingting
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Li Jiaxin
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Zhang Saisai
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Hao Zhitai
- Department of Biochemistry and Molecular Pharmacology, New York University, School of Medicine, NY, USA
| | - Tian Qingnan
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China.
| | - Zhang Shoutao
- School of LifeSciences, Zhengzhou University, Zhengzhou, Henan, China; Henan Key Laboratory of Bioactive Macromolecules, Zhengzhou, Henan, China.
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16
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Strand NS, Allen JM, Zayas RM. Post-translational regulation of planarian regeneration. Semin Cell Dev Biol 2018; 87:58-68. [PMID: 29705300 DOI: 10.1016/j.semcdb.2018.04.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/24/2018] [Accepted: 04/25/2018] [Indexed: 02/07/2023]
Abstract
Most mammals cannot easily overcome degenerative disease or traumatic injuries. In contrast, an innate ability to regenerate is observed across animal phyla. Freshwater planarians are amongst the organisms that are capable of stem cell-mediated whole-body regeneration and have served as an exemplary model to study how pluripotency is maintained and regulated in vivo. Here, we review findings on the role of post-translational modifications and the genes regulating phosphorylation, ubiquitylation, and chromatin remodeling in planarian regeneration. Furthermore, we discuss how technological advances for identifying cellular targets of these processes will fill gaps in our knowledge of the signaling mechanisms that underlie regeneration in planarians, which should inform how tissue repair can be stimulated in non-regenerative model organisms and in humans.
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Affiliation(s)
- Nicholas S Strand
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - John M Allen
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Ricardo M Zayas
- Department of Biology, San Diego State University, San Diego, CA 92182, USA.
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17
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Abstract
Ubiquitin ligases (E3s) are basic components of the eukaryotic ubiquitination system. In this work, the emergence and diversification of fungal HECT ubiquitin ligases is described. Phylogenetic and structural data indicate that six HECT subfamilies (RSP5, TOM1, UFD4, HUL4, HUL4A and HUL5) existed in the common ancestor of all fungi. These six subfamilies have evolved very conservatively, with only occasional losses and duplications in particular fungal lineages. However, an early, drastic reduction in the number of HECT genes occurred in microsporidians, in parallel to the reduction of their genomes. A significant correlation between the total number of genes and the number of HECT-encoding genes present in fungi has been observed. However, transitions from unicellularity to multicellularity or vice versa apparently had no effect on the evolution of this family. Likely orthologs or co-orthologs of all fungal HECT genes have been detected in animals. Four genes are deduced to be present in the common ancestor of fungi, animals and plants. Protein-protein interactions detected in both the yeast Saccharomyces cerevisiae and humans suggest that some ancient functions of HECT proteins have been conserved since the animals/fungi split.
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18
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Rossi L, Salvetti A. Planarian stem cell niche, the challenge for understanding tissue regeneration. Semin Cell Dev Biol 2018. [PMID: 29534938 DOI: 10.1016/j.semcdb.2018.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Stem cell fate depends on surrounding microenvironment, the so called niche. For this reason, understanding stem cell niche is one of the most challenging target in cell biology field and need to be unraveled with in vivo studies. Planarians offer this unique opportunity, as their stem cells, the neoblasts, are abundant, highly characterized and genetically modifiable by RNA interference in alive animals. However, despite impressive advances have been done in the understanding planarian stem cells and regeneration, only a few information is available in defining signals from differentiated tissues, which affect neoblast stemness and fate. Here, we review on molecular factors that have been found activated in differentiated tissues and directly or indirectly affect neoblast behavior, and we suggest future directions for unravelling this challenge in understanding planarian stem cells.
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Affiliation(s)
- Leonardo Rossi
- Departement of Clinical and Experimental Medicine, Unit of Experimental Biology and Genetics, University of Pisa, Via Volta 4 Pisa, Italy
| | - Alessandra Salvetti
- Departement of Clinical and Experimental Medicine, Unit of Experimental Biology and Genetics, University of Pisa, Via Volta 4 Pisa, Italy.
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19
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Strand NS, Allen JM, Ghulam M, Taylor MR, Munday RK, Carrillo M, Movsesyan A, Zayas RM. Dissecting the function of Cullin-RING ubiquitin ligase complex genes in planarian regeneration. Dev Biol 2018; 433:210-217. [PMID: 29291974 DOI: 10.1016/j.ydbio.2017.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/25/2017] [Accepted: 10/11/2017] [Indexed: 12/26/2022]
Abstract
The ubiquitin system plays a role in nearly every aspect of eukaryotic cell biology. The enzymes responsible for transferring ubiquitin onto specific substrates are the E3 ubiquitin ligases, a large and diverse family of proteins, for which biological roles and target substrates remain largely undefined. Studies using model organisms indicate that ubiquitin signaling mediates key steps in developmental processes and tissue regeneration. Here, we used the freshwater planarian, Schmidtea mediterranea, to investigate the role of Cullin-RING ubiquitin ligase (CRL) complexes in stem cell regulation during regeneration. We identified six S. mediterranea cullin genes, and used RNAi to uncover roles for homologs of Cullin-1, -3 and -4 in planarian regeneration. The cullin-1 RNAi phenotype included defects in blastema formation, organ regeneration, lesions, and lysis. To further investigate the function of cullin-1-mediated cellular processes in planarians, we examined genes encoding the adaptor protein Skp1 and F-box substrate-recognition proteins that are predicted to partner with Cullin-1. RNAi against skp1 resulted in phenotypes similar to cullin-1 RNAi, and an RNAi screen of the F-box genes identified 19 genes that recapitulated aspects of cullin-1 RNAi, including ones that in mammals are involved in stem cell regulation and cancer biology. Our data provides evidence that CRLs play discrete roles in regenerative processes and provide a platform to investigate how CRLs regulate stem cells in vivo.
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Affiliation(s)
- Nicholas S Strand
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - John M Allen
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Mahjoobah Ghulam
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Matthew R Taylor
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Roma K Munday
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Melissa Carrillo
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Artem Movsesyan
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Ricardo M Zayas
- Department of Biology, San Diego State University, San Diego, CA 92182, USA.
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20
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Werner A, Manford AG, Rape M. Ubiquitin-Dependent Regulation of Stem Cell Biology. Trends Cell Biol 2017; 27:568-579. [PMID: 28528988 PMCID: PMC5643009 DOI: 10.1016/j.tcb.2017.04.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 04/04/2017] [Accepted: 04/10/2017] [Indexed: 12/21/2022]
Abstract
The growth of a metazoan body relies on a series of highly coordinated cell-fate decisions by stem cells which can undergo self-renewal, reversibly enter a quiescent state, or terminally commit to a cell specification program. To guide their decisions, stem cells make frequent use of ubiquitylation, a post-translational modification that can affect the activity, interaction landscape, or stability of stem cell proteins. In this review we discuss novel findings that have provided insight into ubiquitin-dependent mechanisms of stem cell control and revealed how an essential and highly conserved protein modification can shape metazoan development.
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Affiliation(s)
- Achim Werner
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Andrew G Manford
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Michael Rape
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA 94720, USA.
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21
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McDowell G, Philpott A. New Insights Into the Role of Ubiquitylation of Proteins. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 325:35-88. [DOI: 10.1016/bs.ircmb.2016.02.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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