1
|
Lee M, Youn E, Kang K, Shim YH. 3,3'-Diindolylmethane Supplementation Maintains Oocyte Quality by Reducing Oxidative Stress and CEP-1/p53-Mediated Regulation of Germ Cells in a Reproductively Aged Caenorhabditis elegans Model. Antioxidants (Basel) 2022; 11:950. [PMID: 35624814 PMCID: PMC9137721 DOI: 10.3390/antiox11050950] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/06/2022] [Accepted: 05/08/2022] [Indexed: 11/20/2022] Open
Abstract
In recent decades, maternal age at first birth has increased, as has the risk of infertility due to rapidly declining oocyte quality with age. Therefore, an understanding of female reproductive aging and the development of potential modulators to control oocyte quality are required. In this study, we investigated the effects of 3,3'-diindolylmethane (DIM), a natural metabolite of indole-3-cabinol found in cruciferous vegetables, on fertility in a Caenorhabditis elegans model. C. elegans fed DIM showed decreased mitochondrial dysfunction, oxidative stress, and chromosomal aberrations in aged oocytes, and thus reduced embryonic lethality, suggesting that DIM, a dietary natural antioxidant, improves oocyte quality. Furthermore, DIM supplementation maintained germ cell apoptosis (GCA) and germ cell proliferation (GCP) in a CEP-1/p53-dependent manner in a reproductively aged C. elegans germ line. DIM-induced GCA was mediated by the CEP-1-EGL-1 pathway without HUS-1 activation, suggesting that DIM-induced GCA is different from DNA damage-induced GCA in the C. elegans germ line. Taken together, we propose that DIM supplementation delays the onset of reproductive aging by maintaining the levels of GCP and GCA and oocyte quality in a reproductively aged C. elegans.
Collapse
Affiliation(s)
- Mijin Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
| | - Esther Youn
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
| | - Kyungsu Kang
- Natural Product Informatics Research Center, Korea Institute of Science and Technology, Gangneung 25451, Gangwon-do, Korea;
| | - Yhong-Hee Shim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
| |
Collapse
|
2
|
Ren Z, Geng J, Xiong C, Li X, Li Y, Li J, Liu H. Downregulation of VRK1 reduces the expression of BANF1 and suppresses the proliferative and migratory activity of esophageal cancer cells. Oncol Lett 2020; 20:1163-1170. [PMID: 32724356 PMCID: PMC7377186 DOI: 10.3892/ol.2020.11654] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 04/15/2020] [Indexed: 02/05/2023] Open
Abstract
Esophageal squamous cell carcinoma (ESCC) is a common malignancy worldwide. The disease has a poor prognosis and a low 5-year survival rate. Therefore, it is necessary to identify new strategies to optimize the treatment of ESCC. Vaccinia-related kinase (VRK1) and barrier-to-autointegration factor 1 (BANF1) are overexpressed in ESCC. In the present study, the roles of VRK1 and BANF1 were explored in the development of ESCC. In the present study, the effects of small interfering (si)RNA-induced downregulation of VRK1 on BANF1 expression were investigated as well as the effects on proliferative and migratory activity of ESCC cells. Western blot analysis indicated that the protein expression levels of BANF1 were decreased following siRNA depletion of VRK1. Furthermore, the depletion of VRK1 expression inhibited the proliferation and migration of ESCC cell lines, and flow cytometry analysis indicated that the depletion of VRK1 triggered cell cycle arrest mainly in the S phase. These results suggested that VRK1 and BANF1 may have pivotal roles in the progression of ESCC.
Collapse
Affiliation(s)
- Zhenzhen Ren
- Department of Medical Laboratory, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Jie Geng
- Department of Medical Laboratory, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Chao Xiong
- Department of Medical Laboratory, The Second Affiliated Hospital of Henan University of Traditional Chinese Medicine, Zhengzhou, Henan 450052, P.R. China
| | - Xuebing Li
- Department of Medical Laboratory, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Yuqing Li
- Department of Medical Laboratory, The Second Affiliated Hospital of Henan University of Traditional Chinese Medicine, Zhengzhou, Henan 450052, P.R. China
| | - Jin Li
- Department of Medical Laboratory, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Hongchun Liu
- Department of Medical Laboratory, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| |
Collapse
|
3
|
Park S, Artan M, Han SH, Park HEH, Jung Y, Hwang AB, Shin WS, Kim KT, Lee SJV. VRK-1 extends life span by activation of AMPK via phosphorylation. SCIENCE ADVANCES 2020; 6:6/27/eaaw7824. [PMID: 32937443 PMCID: PMC7458447 DOI: 10.1126/sciadv.aaw7824] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/18/2020] [Indexed: 05/04/2023]
Abstract
Vaccinia virus-related kinase (VRK) is an evolutionarily conserved nuclear protein kinase. VRK-1, the single Caenorhabditis elegans VRK ortholog, functions in cell division and germline proliferation. However, the role of VRK-1 in postmitotic cells and adult life span remains unknown. Here, we show that VRK-1 increases organismal longevity by activating the cellular energy sensor, AMP-activated protein kinase (AMPK), via direct phosphorylation. We found that overexpression of vrk-1 in the soma of adult C. elegans increased life span and, conversely, inhibition of vrk-1 decreased life span. In addition, vrk-1 was required for longevity conferred by mutations that inhibit C. elegans mitochondrial respiration, which requires AMPK. VRK-1 directly phosphorylated and up-regulated AMPK in both C. elegans and cultured human cells. Thus, our data show that the somatic nuclear kinase, VRK-1, promotes longevity through AMPK activation, and this function appears to be conserved between C. elegans and humans.
Collapse
Affiliation(s)
- Sangsoon Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Murat Artan
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Seung Hyun Han
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Hae-Eun H Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Yoonji Jung
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Ara B Hwang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Won Sik Shin
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Kyong-Tai Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea.
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Seung-Jae V Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea.
| |
Collapse
|
4
|
Kincaid-Smith J, Picard MAL, Cosseau C, Boissier J, Severac D, Grunau C, Toulza E. Parent-of-Origin-Dependent Gene Expression in Male and Female Schistosome Parasites. Genome Biol Evol 2018; 10:840-856. [PMID: 29447366 PMCID: PMC5861417 DOI: 10.1093/gbe/evy037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2018] [Indexed: 12/16/2022] Open
Abstract
Schistosomes are the causative agents of schistosomiasis, a neglected tropical disease affecting over 230 million people worldwide. Additionally to their major impact on human health, they are also models of choice in evolutionary biology. These parasitic flatworms are unique among the common hermaphroditic trematodes as they have separate sexes. This so-called “evolutionary scandal” displays a female heterogametic genetic sex-determination system (ZZ males and ZW females), as well as a pronounced adult sexual dimorphism. These phenotypic differences are determined by a shared set of genes in both sexes, potentially leading to intralocus sexual conflicts. To resolve these conflicts in sexually selected traits, molecular mechanisms such as sex-biased gene expression could occur, but parent-of-origin gene expression also provides an alternative. In this work we investigated the latter mechanism, that is, genes expressed preferentially from either the maternal or the paternal allele, in Schistosoma mansoni species. To this end, transcriptomes from male and female hybrid adults obtained by strain crosses were sequenced. Strain-specific single nucleotide polymorphism (SNP) markers allowed us to discriminate the parental origin, while reciprocal crosses helped to differentiate parental expression from strain-specific expression. We identified genes containing SNPs expressed in a parent-of-origin manner consistent with paternal and maternal imprints. Although the majority of the SNPs was identified in mitochondrial and Z-specific loci, the remaining SNPs found in male and female transcriptomes were situated in genes that have the potential to explain sexual differences in schistosome parasites. Furthermore, we identified and validated four new Z-specific scaffolds.
Collapse
Affiliation(s)
- Julien Kincaid-Smith
- IHPE, University of Montpellier, CNRS, IFREMER, University of Perpignan Via Domitia, Perpignan, France
| | - Marion A L Picard
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Céline Cosseau
- IHPE, University of Montpellier, CNRS, IFREMER, University of Perpignan Via Domitia, Perpignan, France
| | - Jérôme Boissier
- IHPE, University of Montpellier, CNRS, IFREMER, University of Perpignan Via Domitia, Perpignan, France
| | - Dany Severac
- MGX, BioCampus Montpellier, CNRS, INSERM, Université de Montpellier, France
| | - Christoph Grunau
- IHPE, University of Montpellier, CNRS, IFREMER, University of Perpignan Via Domitia, Perpignan, France
| | - Eve Toulza
- IHPE, University of Montpellier, CNRS, IFREMER, University of Perpignan Via Domitia, Perpignan, France
| |
Collapse
|
5
|
Lissemore JL, Connors E, Liu Y, Qiao L, Yang B, Edgley ML, Flibotte S, Taylor J, Au V, Moerman DG, Maine EM. The Molecular Chaperone HSP90 Promotes Notch Signaling in the Germline of Caenorhabditis elegans. G3 (BETHESDA, MD.) 2018; 8:1535-1544. [PMID: 29507057 PMCID: PMC5940146 DOI: 10.1534/g3.118.300551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 02/26/2018] [Indexed: 12/27/2022]
Abstract
In a genetic screen to identify genes that promote GLP-1/Notch signaling in Caenorhabditis elegans germline stem cells, we found a single mutation, om40, defining a gene called ego-3. ego-3(om40) causes several defects in the soma and the germline, including paralysis during larval development, sterility, delayed proliferation of germline stem cells, and ectopic germline stem cell proliferation. Whole genome sequencing identified om40 as an allele of hsp-90, previously known as daf-21, which encodes the C. elegans ortholog of the cytosolic form of HSP90. This protein is a molecular chaperone with a central position in the protein homeostasis network, which is responsible for proper folding, structural maintenance, and degradation of proteins. In addition to its essential role in cellular function, HSP90 plays an important role in stem cell maintenance and renewal. Complementation analysis using a deletion allele of hsp-90 confirmed that ego-3 is the same gene. hsp-90(om40) is an I→N conservative missense mutation of a highly conserved residue in the middle domain of HSP-90 RNA interference-mediated knockdown of hsp-90 expression partially phenocopied hsp-90(om40), confirming the loss-of-function nature of hsp-90(om40) Furthermore, reduced HSP-90 activity enhanced the effect of reduced function of both the GLP-1 receptor and the downstream LAG-1 transcription factor. Taken together, our results provide the first experimental evidence of an essential role for HSP90 in Notch signaling in development.
Collapse
Affiliation(s)
- James L Lissemore
- Biology Department, John Carroll University, University Heights, OH 44118
| | - Elyse Connors
- Department of Biology, Syracuse University, NY 13244
| | - Ying Liu
- Department of Biology, Syracuse University, NY 13244
| | - Li Qiao
- Department of Biology, Syracuse University, NY 13244
| | - Bing Yang
- Department of Biology, Syracuse University, NY 13244
| | - Mark L Edgley
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - Stephane Flibotte
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - Jon Taylor
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - Vinci Au
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - Donald G Moerman
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | | |
Collapse
|
6
|
McClendon TB, Mainpal R, Amrit FRG, Krause MW, Ghazi A, Yanowitz JL. X Chromosome Crossover Formation and Genome Stability in Caenorhabditis elegans Are Independently Regulated by xnd-1. G3 (BETHESDA, MD.) 2016; 6:3913-3925. [PMID: 27678523 PMCID: PMC5144962 DOI: 10.1534/g3.116.035725] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 09/21/2016] [Indexed: 01/19/2023]
Abstract
The germ line efficiently combats numerous genotoxic insults to ensure the high fidelity propagation of unaltered genomic information across generations. Yet, germ cells in most metazoans also intentionally create double-strand breaks (DSBs) to promote DNA exchange between parental chromosomes, a process known as crossing over. Homologous recombination is employed in the repair of both genotoxic lesions and programmed DSBs, and many of the core DNA repair proteins function in both processes. In addition, DNA repair efficiency and crossover (CO) distribution are both influenced by local and global differences in chromatin structure, yet the interplay between chromatin structure, genome integrity, and meiotic fidelity is still poorly understood. We have used the xnd-1 mutant of Caenorhabditis elegans to explore the relationship between genome integrity and crossover formation. Known for its role in ensuring X chromosome CO formation and germ line development, we show that xnd-1 also regulates genome stability. xnd-1 mutants exhibited a mortal germ line, high embryonic lethality, high incidence of males, and sensitivity to ionizing radiation. We discovered that a hypomorphic allele of mys-1 suppressed these genome instability phenotypes of xnd-1, but did not suppress the CO defects, suggesting it serves as a separation-of-function allele. mys-1 encodes a histone acetyltransferase, whose homolog Tip60 acetylates H2AK5, a histone mark associated with transcriptional activation that is increased in xnd-1 mutant germ lines, raising the possibility that thresholds of H2AK5ac may differentially influence distinct germ line repair events. We also show that xnd-1 regulated him-5 transcriptionally, independently of mys-1, and that ectopic expression of him-5 suppressed the CO defects of xnd-1 Our work provides xnd-1 as a model in which to study the link between chromatin factors, gene expression, and genome stability.
Collapse
Affiliation(s)
- T Brooke McClendon
- Molecular Genetics and Developmental Biology Graduate Program, University of Pittsburgh School of Medicine, Pennsylvania
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Services University of Pittsburgh School of Medicine, Pennsylvania 15213
| | - Rana Mainpal
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Services University of Pittsburgh School of Medicine, Pennsylvania 15213
| | - Francis R G Amrit
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pennsylvania 15224
| | - Michael W Krause
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892
| | - Arjumand Ghazi
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pennsylvania 15224
| | - Judith L Yanowitz
- Molecular Genetics and Developmental Biology Graduate Program, University of Pittsburgh School of Medicine, Pennsylvania
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Services University of Pittsburgh School of Medicine, Pennsylvania 15213
| |
Collapse
|
7
|
Dobrzynska A, Askjaer P. Vaccinia-related kinase 1 is required for early uterine development in Caenorhabditis elegans. Dev Biol 2016; 411:246-256. [PMID: 26827901 DOI: 10.1016/j.ydbio.2016.01.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 10/25/2022]
Abstract
Protein kinases regulate a multitude of processes by reversible phosphorylation of target molecules. Induction of cell proliferation and differentiation are fundamental to development and rely on tightly controlled kinase activities. Vaccinia-Related Kinases (VRKs) have emerged as a multifunctional family of kinases with essential functions conserved, from nematodes and fruit flies, to humans. VRK substrates include chromatin and transcription factors, whereas deregulation of VRKs is implicated in sterility, cancer and neurological defects. In contrast to previous observations, we describe here that Caenorhabditis elegans VRK-1 is expressed in all cell types, including proliferating and post-mitotic cells. Despite the ubiquitous expression pattern, we find that vrk-1 mutants are particularly impaired in uterine development. Our data show that VRK-1 is required for uterine cell proliferation and differentiation. Moreover, the anchor cell, a specialized uterine cell, fails to fuse with neighboring cells to form the utse syncytium in vrk-1 mutants, thus providing further insight on the role of VRKs in organogenesis.
Collapse
Affiliation(s)
- Agnieszka Dobrzynska
- Andalusian Center for Developmental Biology, CSIC-Junta de Andalucia-Universidad Pablo de Olavide, Carretera de Utrera, km 1, 41013 Seville, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology, CSIC-Junta de Andalucia-Universidad Pablo de Olavide, Carretera de Utrera, km 1, 41013 Seville, Spain.
| |
Collapse
|
8
|
Turner BE, Basecke SM, Bazan GC, Dodge ES, Haire CM, Heussman DJ, Johnson CL, Mukai CK, Naccarati AM, Norton SJ, Sato JR, Talavera CO, Wade MV, Hillers KJ. Proteomic identification of germline proteins in Caenorhabditis elegans. WORM 2015; 4:e1008903. [PMID: 26435885 DOI: 10.1080/21624054.2015.1008903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 11/30/2014] [Accepted: 01/13/2015] [Indexed: 01/06/2023]
Abstract
Sexual reproduction involves fusion of 2 haploid gametes to form diploid offspring with genetic contributions from both parents. Gamete formation represents a unique developmental program involving the action of numerous germline-specific proteins. In an attempt to identify novel proteins involved in reproduction and embryonic development, we have carried out a proteomic characterization of the process in Caenorhabditis elegans. To identify candidate proteins, we used 2D gel electrophoresis (2DGE) to compare protein abundance in nucleus-enriched extracts from wild-type C. elegans, and in extracts from mutant worms with greatly reduced gonads (glp-4(bn2) worms reared at 25°C); 84 proteins whose abundance correlated with germline presence were identified. To validate candidates, we used feeding RNAi to deplete candidate proteins, and looked for reduction in fertility and/or germline cytological defects. Of 20 candidates so screened for involvement in fertility, depletion of 13 (65%) caused a significant reduction in fertility, and 6 (30%) resulted in sterility (<5 % of wild-type fertility). Five of the 13 proteins with demonstrated roles in fertility have not previously been implicated in germline function. The high frequency of defects observed after RNAi depletion of candidate proteins suggests that this approach is effective at identifying germline proteins, thus contributing to our understanding of this complex organ.
Collapse
Affiliation(s)
- B Elizabeth Turner
- Department of Chemistry and Biochemistry; California Polytechnic State University ; San Luis Obispo, CA USA ; ; Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Sophia M Basecke
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Grace C Bazan
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Eric S Dodge
- Department of Chemistry and Biochemistry; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Cassy M Haire
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Dylan J Heussman
- Department of Chemistry and Biochemistry; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Chelsey L Johnson
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Chelsea K Mukai
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Adrianna M Naccarati
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Sunny-June Norton
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Jennifer R Sato
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Chihara O Talavera
- Department of Chemistry and Biochemistry; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Michael V Wade
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| | - Kenneth J Hillers
- Department of Biological Sciences; California Polytechnic State University ; San Luis Obispo, CA USA
| |
Collapse
|
9
|
Ito S, Akamatsu Y, Noma A, Kimura S, Miyauchi K, Ikeuchi Y, Suzuki T, Suzuki T. A single acetylation of 18 S rRNA is essential for biogenesis of the small ribosomal subunit in Saccharomyces cerevisiae. J Biol Chem 2014; 289:26201-26212. [PMID: 25086048 DOI: 10.1074/jbc.m114.593996] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Biogenesis of eukaryotic ribosome is a complex event involving a number of non-ribosomal factors. During assembly of the ribosome, rRNAs are post-transcriptionally modified by 2'-O-methylation, pseudouridylation, and several base-specific modifications, which are collectively involved in fine-tuning translational fidelity and/or modulating ribosome assembly. By mass-spectrometric analysis, we demonstrated that N(4)-acetylcytidine (ac(4)C) is present at position 1773 in the 18 S rRNA of Saccharomyces cerevisiae. In addition, we found an essential gene, KRE33 (human homolog, NAT10), that we renamed RRA1 (ribosomal RNA cytidine acetyltransferase 1) encoding an RNA acetyltransferase responsible for ac(4)C1773 formation. Using recombinant Rra1p, we could successfully reconstitute ac(4)C1773 in a model rRNA fragment in the presence of both acetyl-CoA and ATP as substrates. Upon depletion of Rra1p, the 23 S precursor of 18 S rRNA was accumulated significantly, which resulted in complete loss of 18 S rRNA and small ribosomal subunit (40 S), suggesting that ac(4)C1773 formation catalyzed by Rra1p plays a critical role in processing of the 23 S precursor to yield 18 S rRNA. When nuclear acetyl-CoA was depleted by inactivation of acetyl-CoA synthetase 2 (ACS2), we observed temporal accumulation of the 23 S precursor, indicating that Rra1p modulates biogenesis of 40 S subunit by sensing nuclear acetyl-CoA concentration.
Collapse
Affiliation(s)
- Satoshi Ito
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yu Akamatsu
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Akiko Noma
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Satoshi Kimura
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kenjyo Miyauchi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yoshiho Ikeuchi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeo Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
| |
Collapse
|
10
|
Wang Y, Wang S, Luo X, Yang Y, Jian F, Wang X, Xie L. The roles of DNA damage-dependent signals and MAPK cascades in tributyltin-induced germline apoptosis in Caenorhabditis elegans. CHEMOSPHERE 2014; 108:231-238. [PMID: 24534158 DOI: 10.1016/j.chemosphere.2014.01.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 12/23/2013] [Accepted: 01/11/2014] [Indexed: 06/03/2023]
Abstract
The induction of apoptosis is recognized to be a major mechanism of tributyltin (TBT) toxicity. However, the underlying signaling pathways for TBT-induced apoptosis remain unclear. In this study, using the nematode Caenorhabditis elegans, we examined whether DNA damage response (DDR) pathway and mitogen-activated protein kinase (MAPK) signaling cascades are involved in TBT-induced germline apoptosis and cell cycle arrest. Our results demonstrated that exposing worms to TBT at the dose of 10nM for 6h significantly increased germline apoptosis in N2 strain. Germline apoptosis was absent in strains that carried ced-3 or ced-4 loss-of-function alleles, indicating that both caspase protein CED-3 and Apaf-1 protein CED-4 were required for TBT-induced apoptosis. TBT-induced apoptosis was blocked in the Bcl-2 gain-of-function strain ced-9(n1950), whereas TBT induced a minor increase in the BH3-only protein EGL-1 mutated strain egl-1(n1084n3082). Checkpoint proteins HUS-1 and CLK-2 exerted proapoptotic effects, and the null mutation of cep-1, the homologue of tumor suppressor gene p53, significantly inhibited TBT-induced apoptosis. Apoptosis in the loss-of-function strains of ERK, JNK and p38 MAPK signaling pathways were completely or mildly suppressed under TBT stress. These results were supported by the results of mRNA expression levels of corresponding genes. The present study indicated that TBT-induced apoptosis required the core apoptotic machinery, and that DDR genes and MAPK pathways played essential roles in signaling the processes.
Collapse
Affiliation(s)
- Yun Wang
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China.
| | - Shunchang Wang
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| | - Xun Luo
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| | - Yanan Yang
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| | - Fenglei Jian
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| | - Xuemin Wang
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| | - Lucheng Xie
- Department of Life Sciences, Huainan Normal University, Huainan, Anhui 232001, PR China
| |
Collapse
|
11
|
Vergara IA, Tarailo-Graovac M, Frech C, Wang J, Qin Z, Zhang T, She R, Chu JSC, Wang K, Chen N. Genome-wide variations in a natural isolate of the nematode Caenorhabditis elegans. BMC Genomics 2014; 15:255. [PMID: 24694239 PMCID: PMC4023591 DOI: 10.1186/1471-2164-15-255] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Accepted: 03/03/2014] [Indexed: 12/02/2022] Open
Abstract
Background Increasing genetic and phenotypic differences found among natural isolates of C. elegans have encouraged researchers to explore the natural variation of this nematode species. Results Here we report on the identification of genomic differences between the reference strain N2 and the Hawaiian strain CB4856, one of the most genetically distant strains from N2. To identify both small- and large-scale genomic variations (GVs), we have sequenced the CB4856 genome using both Roche 454 (~400 bps single reads) and Illumina GA DNA sequencing methods (101 bps paired-end reads). Compared to previously described variants (available in WormBase), our effort uncovered twice as many single nucleotide variants (SNVs) and increased the number of small InDels almost 20-fold. Moreover, we identified and validated large insertions, most of which range from 150 bps to 1.2 kb in length in the CB4856 strain. Identified GVs had a widespread impact on protein-coding sequences, including 585 single-copy genes that have associated severe phenotypes of reduced viability in RNAi and genetics studies. Sixty of these genes are homologs of human genes associated with diseases. Furthermore, our work confirms previously identified GVs associated with differences in behavioural and biological traits between the N2 and CB4856 strains. Conclusions The identified GVs provide a rich resource for future studies that aim to explain the genetic basis for other trait differences between the N2 and CB4856 strains.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Nansheng Chen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada.
| |
Collapse
|
12
|
López-Sánchez I, Valbuena A, Vázquez-Cedeira M, Khadake J, Sanz-García M, Carrillo-Jiménez A, Lazo PA. VRK1 interacts with p53 forming a basal complex that is activated by UV-induced DNA damage. FEBS Lett 2014; 588:692-700. [PMID: 24492002 DOI: 10.1016/j.febslet.2014.01.040] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/09/2014] [Accepted: 01/19/2014] [Indexed: 01/08/2023]
Abstract
DNA damage immediate cellular response requires the activation of p53 by kinases. We found that p53 forms a basal stable complex with VRK1, a Ser-Thr kinase that responds to UV-induced DNA damage by specifically phosphorylating p53. This interaction takes place through the p53 DNA binding domain, and frequent DNA-contact mutants of p53, such as R273H, R248H or R280K, do not disrupt the complex. UV-induced DNA damage activates VRK1, and is accompanied by phosphorylation of p53 at Thr-18 before it accumulates. We propose that the VRK1-p53 basal complex is an early-warning system for immediate cellular responses to DNA damage.
Collapse
Affiliation(s)
- Inmaculada López-Sánchez
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain
| | - Alberto Valbuena
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain
| | - Marta Vázquez-Cedeira
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - Jyoti Khadake
- European Bioinformatics Institute-EMBL, Cambridge, England, United Kingdom
| | - Marta Sanz-García
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain
| | - Alejandro Carrillo-Jiménez
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain
| | - Pedro A Lazo
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain.
| |
Collapse
|
13
|
Berber S, Llamosas E, Thaivalappil P, Boag PR, Crossley M, Nicholas HR. Homeodomain interacting protein kinase (HPK-1) is required in the soma for robust germline proliferation in C. elegans. Dev Dyn 2013; 242:1250-61. [PMID: 23904186 DOI: 10.1002/dvdy.24023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 07/15/2013] [Accepted: 07/16/2013] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Tightly regulated pathways maintain the balance between proliferation and differentiation within stem cell populations. In Caenorhabditis elegans, the germline is the only tissue that is maintained by stem-like cells into adulthood. In the current study, we investigated the role played by a member of the Homeodomain interacting protein kinase (HIPK) family of serine/threonine kinases, HPK-1, in the development and maintenance of the C. elegans germline. RESULTS We report that HPK-1 is required for promotion of germline proliferation during development and into adulthood. Additionally, we show that HPK-1 is required in the soma for regulation of germline proliferation. We also show that HPK-1 is a predominantly nuclear protein expressed in several somatic tissues including germline-interacting somatic cells. CONCLUSIONS Our observations are consistent with a conserved role for HIPKs in the control of cellular proliferation and identify a new context for such control in germ cell proliferation.
Collapse
Affiliation(s)
- Slavica Berber
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | | | | | | | | | | |
Collapse
|
14
|
Kershner A, Crittenden SL, Friend K, Sorensen EB, Porter DF, Kimble J. Germline stem cells and their regulation in the nematode Caenorhabditis elegans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 786:29-46. [PMID: 23696350 DOI: 10.1007/978-94-007-6621-1_3] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
C. elegans germline stem cells exist within a stem cell pool that is maintained by a single-celled mesenchymal niche and Notch signaling. Downstream of Notch signaling, a regulatory network governs stem cells and differentiation. Central to that network is the FBF RNA-binding protein, a member of the widely conserved PUF family that functions by either of two broadly conserved mechanisms to repress its target mRNAs. Without FBF, germline stem cells do not proliferate and they do not maintain their naïve, undifferentiated state. Therefore, FBF is a pivotal regulator of germline self-renewal. Validated FBF targets include several key differentiation regulators as well as a major cell cycle regulator. A genomic analysis identifies many other developmental and cell cycle regulators as likely FBF targets and suggests that FBF is a broad-spectrum regulator of the genome with >1,000 targets. A comparison of the FBF target list with similar lists for human PUF proteins, PUM1 and PUM2, reveals ∼200 shared targets. The FBF hub works within a network controlling self-renewal vs. differentiation. This network consists of classical developmental cell fate regulators and classical cell cycle regulators. Recent results have begun to integrate developmental and cell cycle regulation within the network. The molecular dynamics of the network remain a challenge for the future, but models are proposed. We suggest that molecular controls of C. elegans germline stem cells provide an important model for controls of stem cells more broadly.
Collapse
Affiliation(s)
- Aaron Kershner
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA
| | | | | | | | | | | |
Collapse
|
15
|
Jolliffe AK, Derry WB. The TP53 signaling network in mammals and worms. Brief Funct Genomics 2012; 12:129-41. [PMID: 23165352 DOI: 10.1093/bfgp/els047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The nematode worm Caenorhabditis elegans has been an invaluable model organism for studying the molecular mechanisms that govern cell fate, from fundamental aspects of multicellular development to programmed cell death (apoptosis). The transparency of this organism permits visualization of cells in living animals at high resolution. The powerful genetics and functional genomics tools available in C. elegans allow for detailed analysis of gene function, including genes that are frequently deregulated in human diseases such as cancer. The TP53 protein is a critical suppressor of tumor formation in vertebrates, and the TP53 gene is mutated in over 50% of human cancers. TP53 suppresses malignancy by integrating a variety of cellular stresses that direct it to activate transcription of genes that help to repair the damage or trigger apoptotic death if the damage is beyond repair. The TP53 paralogs, TP63 and TP73, have distinct roles in development as well as overlapping functions with TP53 in apoptosis and repair, which complicates their analysis in vertebrates. C. elegans contains a single TP53 family member, cep-1, that shares properties of all three vertebrate genes and thus offers a simple system in which to study the biological functions of this important gene family. This review summarizes major advances in our understanding of the TP53 family using C. elegans as a model organism.
Collapse
|
16
|
Ren G, Yu B. Critical roles of RNA-binding proteins in miRNA biogenesis in Arabidopsis. RNA Biol 2012; 9:1424-8. [PMID: 23135480 DOI: 10.4161/rna.22740] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
MicroRNAs (miRNAs) are key regulators of gene expression and play critical roles in modulating metabolism, development and physiology in animals and plants. miRNA levels are transcriptionally and post-transcriptionally controlled for their proper function. Recent studies have shown that RNA-binding proteins play important roles in producing miRNAs by affecting the accurate and/or efficient processing of precursors of miRNAs. Many of these RNA-binding proteins also have roles in general RNA metabolism, indicating potential connections between miRNA biogenesis and other RNA metabolism. Here, we focus on the function of several RNA-binding proteins in miRNA biogenesis in Arabidopsis.
Collapse
Affiliation(s)
- Guodong Ren
- Center for Plant Science Innovation & School of Biological Sciences; University of Nebraska; Lincoln, NE USA
| | | |
Collapse
|
17
|
Regulation of miRNA abundance by RNA binding protein TOUGH in Arabidopsis. Proc Natl Acad Sci U S A 2012; 109:12817-21. [PMID: 22802657 DOI: 10.1073/pnas.1204915109] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
MicroRNAs (miRNAs) are regulators of gene expression in plants and animals. The biogenesis of miRNAs is precisely controlled to secure normal development of organisms. Here we report that TOUGH (TGH) is a component of the DCL1-HYL1-SERRATE complex that processes primary transcripts of miRNAs [i.e., primary miRNAs (pri-miRNAs)] into miRNAs in Arabidopsis. Lack of TGH impairs multiple DCL activities in vitro and reduces the accumulation of miRNAs and siRNAs in vivo. TGH is an RNA-binding protein, binds pri-miRNAs and precursor miRNAs in vivo, and contributes to pri-miRNA-HYL1 interaction. These results indicate that TGH might regulate abundance of miRNAs through promoting DCL1 cleavage efficiency and/or recruitment of pri-miRNAs.
Collapse
|
18
|
Tobin DV, Saito RM. Developmental decisions: balancing genetics and the environment by C. elegans. Cell Cycle 2012; 11:1666-71. [PMID: 22510569 DOI: 10.4161/cc.19443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The small nematode C. elegans is characterized by developing through a highly coordinated, reproducible cell lineage that serves as the basis of many studies focusing on the development of multi-lineage organisms. Indeed, the reproducible cell lineage enables discovery of developmental defects that occur in even a single cell. Only recently has attention been focused on how these animals modify their genetically programmed cell lineages to adapt to altered environments. Here, we summarize the current understanding of how C. elegans responds to food deprivation by adapting their developmental program in order to conserve energy. In particular, we highlight the AMPK-mediated and insulin-like growth factor signaling pathways that are the principal regulators of induced cell cycle quiescence.
Collapse
Affiliation(s)
- David V Tobin
- Department of Genetics, Dartmouth Medical School, Hanover, NH, USA
| | | |
Collapse
|
19
|
McGee MD, Day N, Graham J, Melov S. cep-1/p53-dependent dysplastic pathology of the aging C. elegans gonad. Aging (Albany NY) 2012; 4:256-69. [PMID: 22562940 PMCID: PMC3378273 DOI: 10.18632/aging.100448] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The C. elegans germline and somatic gonad are actively developing until the animal reaches adulthood, and then continue to undergo striking changes as the animal ages. Reported changes include a depletion of available sperm, a decrease in oocyte quality up till mid-life, a reduction in germline nuclei, a decrease in fertility, and an accumulation of DNA in the midbody of aging C. elegans. Here, we have focused on the aging gonad in old animals, and show in detail that the aging gonad undergoes a massive uterine growth composed of endoreduplicating oocytes, yolk, and expanses of chromatin. We use a novel series of imaging techniques in combination with histological methodology for reconstructing aged worms in 3-dimensions, and show in old animals growing masses swelling inside the uterus to occupy most of the diameter of the worm. We link this accelerated growth to the cep-1/p53 tumor suppressor. Because cep-1 is required for DNA damage induced apoptosis, and daf-2 limits longevity, these results suggest a role for age-related DNA damage in dysplastic uterine growths, which in some respects resemble premalignant changes that can occur in aging mammals.
Collapse
Affiliation(s)
- Mathew D McGee
- Buck Institute for Research on Aging, Novato, CA 94945, USA
| | | | | | | |
Collapse
|
20
|
van den Ecker D, van den Brand MA, Ariaans G, Hoffmann M, Bossinger O, Mayatepek E, Nijtmans LG, Distelmaier F. Identification and functional analysis of mitochondrial complex I assembly factor homologues in C. elegans. Mitochondrion 2012; 12:399-405. [PMID: 22387847 DOI: 10.1016/j.mito.2012.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Revised: 01/17/2012] [Accepted: 01/26/2012] [Indexed: 01/01/2023]
Abstract
The biogenesis of mitochondrial NADH:ubiquinone oxidoreductase (complex I) requires several assembly chaperones. These so-called complex I assembly factors have emerged as a new class of human disease genes. Here, we identified putative assembly factor homologues in Caenorhabditis elegans. We demonstrate that two candidates (C50B8.3/NUAF-1, homologue of NDUFAF1 and R07H5.3/NUAF-3, homologue of NDUFAF3) clearly affect complex I function. Assembly factor deficient worms were shorter, showed a diminished brood size and displayed reduced fat content. Our results suggest that mitochondrial complex I biogenesis is evolutionarily conserved. Moreover, Caenorhabditis elegans appears to be a promising model organism to study assembly factor related human diseases.
Collapse
Affiliation(s)
- Daniela van den Ecker
- Department of General Pediatrics and Neonatology, University Children's Hospital, Heinrich-Heine-University, Düsseldorf, Germany
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Valbuena A, Sanz-García M, López-Sánchez I, Vega FM, Lazo PA. Roles of VRK1 as a new player in the control of biological processes required for cell division. Cell Signal 2011; 23:1267-72. [PMID: 21514377 DOI: 10.1016/j.cellsig.2011.04.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 04/04/2011] [Indexed: 11/28/2022]
Abstract
Cell division, in addition to an accurate transmission of genetic information to daughter cells, also requires the temporal and spatial coordination of several biological processes without which cell division would not be feasible. These processes include the temporal coordination of DNA replication and chromosome segregation, regulation of nuclear envelope disassembly and assembly, chromatin condensation and Golgi fragmentation for its redistribution into daughter cells, among others. However, little is known regarding regulatory proteins and signalling pathways that might participate in the coordination of all these different biological functions. Such regulatory players should directly have a role in the processes leading to cell division. VRK1 (Vaccinia-related kinase 1) is an early response gene required for cyclin D1 expression, regulates p53 by a specific Thr18 phosphorylation, controls chromatin condensation by histone phosphorylation, nuclear envelope assembly by phosphorylation of BANF1, and participates in signalling required for Golgi fragmentation late in the G2 phase. We propose that VRK1, a Ser-Thr kinase, might be a candidate to play an important coordinator role in these cell division processes as part of a novel signalling pathway.
Collapse
Affiliation(s)
- Alberto Valbuena
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, Campus Miguel de Unamuno, E-37007 Salamanca, Spain
| | | | | | | | | |
Collapse
|
22
|
Waters KA, Reinke V. Extrinsic and intrinsic control of germ cell proliferation in Caenorhabditis elegans. Mol Reprod Dev 2011; 78:151-60. [PMID: 21337453 DOI: 10.1002/mrd.21289] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 01/06/2011] [Indexed: 12/23/2022]
Abstract
The germ cells of Caenorhabditis elegans serve as a useful model to study the balance between proliferation and differentiation within the context of development and changing environmental signals experienced by the animal. Germ cells adjacent to a stem cell niche in the distal region of the gonad retain the capacity to divide during adulthood, making them unique from other cells in the organism. We will highlight recent advances in our understanding of mechanisms that control proliferation, as well as the signaling pathways involved in promoting mitosis at the expense of differentiation.
Collapse
|
23
|
Schober CS, Aydiner F, Booth CJ, Seli E, Reinke V. The kinase VRK1 is required for normal meiotic progression in mammalian oogenesis. Mech Dev 2011; 128:178-90. [PMID: 21277975 DOI: 10.1016/j.mod.2011.01.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 01/19/2011] [Accepted: 01/20/2011] [Indexed: 01/02/2023]
Abstract
The kinase VRK1 has been implicated in mitotic and meiotic progression in invertebrate species, but whether it mediates these events during mammalian gametogenesis is not completely understood. Previous work has demonstrated a role for mammalian VRK1 in proliferation of male spermatogonia, yet whether VRK1 plays a role in meiotic progression, as seen in Drosophila, has not been determined. Here, we have established a mouse strain bearing a gene trap insertion in the VRK1 locus that disrupts Vrk1 expression. In addition to the male proliferation defects, we find that reduction of VRK1 activity causes a delay in meiotic progression during oogenesis, results in the presence of lagging chromosomes during formation of the metaphase plate, and ultimately leads to the failure of oocytes to be fertilized. The activity of at least one phosphorylation substrate of VRK1, p53, is not required for these defects. These results are consistent with previously defined functions of VRK1 in meiotic progression in Drosophila oogenesis, and indicate a conserved role for VRK1 in coordinating proper chromosomal configuration in female meiosis.
Collapse
Affiliation(s)
- Carolyn S Schober
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | | | | | | | | |
Collapse
|