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Wu Y, Ma Y, Zhong W, Shen H, Ye J, Du S, Li P. Alleviation of endothelial dysfunction of Pheretima guillemi (Michaelsen)-derived protein DPf3 in ponatinib-induced thrombotic zebrafish and mechanisms explored through ox-LDL-induced HUVECs and TMT-based proteomics. JOURNAL OF ETHNOPHARMACOLOGY 2024; 323:117669. [PMID: 38159828 DOI: 10.1016/j.jep.2023.117669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Thrombus generation is one of the leading causes of death in human, and vascular endothelial dysfunction is a major contributor to thrombosis. Pheretima guillemi (Michaelsen), a traditional medicinal animal known as "Dilong", has been utilized to cure thrombotic disorders for many years. DPf3, a group of functional proteins extracted from P. guillemi, has been characterized and identified to possess antithrombotic bioactivity via in vitro and ex vivo experiments. AIM OF THE STUDY This study is aimed to investigate the vascular-protection activity and related mechanism of antithrombotic protein DPf3 purified from Pheretima guillelmi systematically. MATERIALS AND METHODS The antithrombotic activity and vascular endothelium protection effect of DPf3 was explored in vivo using ponatinib-induced vascular endothelial injury zebrafish thrombus model. Then, (hi) ox-LDL-induced HUVECs was applied to investigate the protection mechanism of DPf3 against the injury of vascular endothelium. In addition, TMT-based proteomics analysis was used to study the biomarkers, biological processes and signal pathways involved in the antithrombotic and vascular protective effects of DPf3 holistically. RESULTS DPf3 exerted robust in vivo antithrombosis and vascular endothelial protection ability. DPf3 was identified to prevent HUVECs from damage by reducing ROS production, and to reduce monocyte adhesion by decreasing the protein content of adhesion factor VCAM 1. DPf3 was also observed to weaken the migration ability of injured cells and inhibit abnormal angiogenesis. The mechanism of DPf3's antithrombotic and vascular protective activity was mainly related to the regulation of lipid metabolism, energy metabolism, complement and coagulation system, ECM receptor interaction, MAPK signal pathway, etc. CONCLUSIONS: This study demonstrates that DPf3 has strong antithrombotic and endothelial protective effects. The endothelial protective ability and related mechanisms of DPf3 provide a scientific reference for the traditional use of earthworms in the treatment of thrombosis.
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Affiliation(s)
- Yali Wu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China; Henan Province Engineering Laboratory for Clinical Evaluation Technology of Chinese Medicine, Henan Provincial Key Laboratory for Clinical Pharmacy of Traditional Chinese Medicine, The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, 450000, China.
| | - Yunnan Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Wanling Zhong
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Huijuan Shen
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Jinhong Ye
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Shouying Du
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Pengyue Li
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
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Steinbach MK, Leipert J, Blurton C, Leippe M, Tholey A. Digital Microfluidics Supported Microproteomics for Quantitative Proteome Analysis of Single Caenorhabditis elegans Nematodes. J Proteome Res 2022; 21:1986-1996. [PMID: 35771142 DOI: 10.1021/acs.jproteome.2c00274] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Miniaturization of sample preparation, including omissible manual sample handling steps, is key for reproducible nanoproteomics, as material is often restricted to only hundreds of cells or single model organisms. Here, we demonstrate a highly sensitive digital microfluidics (DMF)-based sample preparation workflow making use of single-pot solid-phase enhanced sample preparation (SP3) in combination with high-field asymmetric-waveform ion mobility spectrometry (FAIMS), and fast and sensitive ion trap detection on an Orbitrap tribrid MS system. Compared to a manual in-tube SP3-supported sample preparation, the numbers of identified peptides and proteins were markedly increased, while lower standard deviations between replicates were observed. We repeatedly identified up to 5000 proteins from single nematodes. Moreover, label-free quantification of protein changes in single Caenorhabditis elegans treated with a heat stimulus yielded 45 differentially abundant proteins when compared to the untreated control, highlighting the potential of this technology for low-input proteomics studies. LC-MS data have been deposited to the ProteomeXchange Consortium with the data set identifier PXD033143.
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Affiliation(s)
- Max K Steinbach
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Jan Leipert
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Christine Blurton
- Comparative Immunobiology, Zoological Institute, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Matthias Leippe
- Comparative Immunobiology, Zoological Institute, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Andreas Tholey
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
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3
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Rosario R, Stewart HL, Walshe E, Anderson RA. Reduced retinoic acid synthesis accelerates prophase I and follicle activation. Reproduction 2021; 160:331-341. [PMID: 32520724 PMCID: PMC7424351 DOI: 10.1530/rep-20-0221] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/08/2020] [Indexed: 12/16/2022]
Abstract
In female mammals, reproductive potential is determined during fetal life by the formation of a non-renewable pool of primordial follicles. Initiation of meiosis is one of the defining features of germ cell differentiation and is well established to commence in response to retinoic acid. WIN 18,446 inhibits the conversion of retinol to retinoic acid, and therefore it was used to explore the impact of reduced retinoic acid synthesis on meiotic progression and thus germ cell development and subsequent primordial follicle formation. e13.5 mouse fetal ovaries were cultured in vitro and treated with WIN 18,446 for the first 3 days of a total of up to 12 days. Doses as low as 0.01 µM reduced transcript levels of the retinoic acid response genes Stra8 and Rarβ without affecting germ cell number. Higher doses resulted in germ cell loss, rescued with the addition of retinoic acid. WIN 18,446 significantly accelerated the progression of prophase I; this was seen as early as 48 h post treatment using meiotic chromosome spreads and was still evident after 12 days of culture using Tra98/Msy2 immunostaining. Furthermore, ovaries treated with WIN 18,446 at e13.5 but not at P0 had a higher proportion of growing follicles compared to vehicle controls, thus showing evidence of increased follicle activation. These data therefore indicate that retinoic acid is not necessary for meiotic progression but may have a role in the regulation of its progression and germ cell survival at that time and provide evidence for a link between meiotic arrest and follicle growth initiation.
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Affiliation(s)
- Roseanne Rosario
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Hazel L Stewart
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Emily Walshe
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Richard A Anderson
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
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Achache H, Falk R, Lerner N, Beatus T, Tzur YB. Oocyte aging is controlled by mitogen-activated protein kinase signaling. Aging Cell 2021; 20:e13386. [PMID: 34061407 PMCID: PMC8208789 DOI: 10.1111/acel.13386] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 03/25/2021] [Accepted: 05/08/2021] [Indexed: 12/11/2022] Open
Abstract
Oogenesis is one of the first processes to fail during aging. In women, most oocytes cannot successfully complete meiotic divisions already during the fourth decade of life. Studies of the nematode Caenorhabditis elegans have uncovered conserved genetic pathways that control lifespan, but our knowledge regarding reproductive aging in worms and humans is limited. Specifically, little is known about germline internal signals that dictate the oogonial biological clock. Here, we report a thorough characterization of the changes in the worm germline during aging. We found that shortly after ovulation halts, germline proliferation declines, while apoptosis continues, leading to a gradual reduction in germ cell numbers. In late aging stages, we observed that meiotic progression is disturbed and crossover designation and DNA double-strand break repair decrease. In addition, we detected a decline in the quality of mature oocytes during aging, as reflected by decreasing size and elongation of interhomolog distance, a phenotype also observed in human oocytes. Many of these altered processes were previously attributed to MAPK signaling variations in young worms. In support of this, we observed changes in activation dynamics of MPK-1 during aging. We therefore tested the hypothesis that MAPK controls oocyte quality in aged worms using both genetic and pharmacological tools. We found that in mutants with high levels of activated MPK-1, oocyte quality deteriorates more rapidly than in wild-type worms, whereas reduction of MPK-1 levels enhances quality. Thus, our data suggest that MAPK signaling controls germline aging and could be used to attenuate the rate of oogenesis quality decline.
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Affiliation(s)
- Hanna Achache
- Department of GeneticsInstitute of Life SciencesThe Hebrew University of JerusalemJerusalemIsrael
| | - Roni Falk
- Department of GeneticsInstitute of Life SciencesThe Hebrew University of JerusalemJerusalemIsrael
| | - Noam Lerner
- Department of NeurobiologyThe Institute of Life ScienceThe Hebrew University of JerusalemJerusalemIsrael
- The Alexander Grass Center for BioengineeringThe Rachel and Selim Benin School of Computer Science and EngineeringThe Hebrew University of JerusalemJerusalemIsrael
| | - Tsevi Beatus
- Department of NeurobiologyThe Institute of Life ScienceThe Hebrew University of JerusalemJerusalemIsrael
- The Alexander Grass Center for BioengineeringThe Rachel and Selim Benin School of Computer Science and EngineeringThe Hebrew University of JerusalemJerusalemIsrael
| | - Yonatan B. Tzur
- Department of GeneticsInstitute of Life SciencesThe Hebrew University of JerusalemJerusalemIsrael
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5
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Transcriptome and MiRNAomics Analyses Identify Genes Associated with Cytoplasmic Male Sterility in Cotton ( Gossypium hirsutum L.). Int J Mol Sci 2021; 22:ijms22094684. [PMID: 33925234 PMCID: PMC8124215 DOI: 10.3390/ijms22094684] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/25/2021] [Accepted: 04/26/2021] [Indexed: 11/17/2022] Open
Abstract
Cytoplasmic male sterility (CMS) is important for large-scale hybrid seed production. Rearrangements in the mitochondrial DNA (mtDNA) for the cotton (Gossypium hirsutum L.) CMS line J4A were responsible for pollen abortion. However, the expression patterns of nuclear genes associated with pollen abortion and the molecular basis of CMS for J4A are unknown, and were the objectives of this study by comparing J4A with the J4B maintainer line. Cytological evaluation of J4A anthers showed that microspore abortion occurs during meiosis preventing pollen development. Changes in enzyme activity of mitochondrial respiratory chain complex IV and mitochondrial respiratory chain complex V and the content of ribosomal protein and ATP during anther abortion were observed for J4A suggesting insufficient synthesis of ATP hindered pollen production. Additionally, levels of sucrose, starch, soluble sugar, and fructose were significantly altered in J4A during the meiosis stage, suggesting reduced sugar metabolism contributed to sterility. Transcriptome and miRNAomics analyses identified 4461 differentially expressed mRNAs (DEGs) and 26 differentially expressed microRNAs (DEMIs). Pathway enrichment analysis indicated that the DEMIs were associated with starch and sugar metabolism. Six deduced target gene regulatory pairs that may participate in CMS were identified, ghi-MIR7484-10/mitogen-activated protein kinase kinase 6 (MAPKK6), ghi-undef-156/agamous-like MADS-box protein AGL19 (AGL19), ghi-MIR171-1-22/SNF1-related protein kinase regulatory subunit gamma-1 and protein trichome birefringence-like 38, and ghi-MIR156-(8/36)/WRKY transcription factor 28 (WRKY28). Overall, a putative CMS mechanism involving mitochondrial dysfunction, the ghi-MIR7484-10/MAPKK6 network, and reduced glucose metabolism was suggested, and ghi-MIR7484-10/MAPKK6 may be related to abnormal microspore meiosis and induction of excessive sucrose accumulation in anthers.
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HIM-17 regulates the position of recombination events and GSP-1/2 localization to establish short arm identity on bivalents in meiosis. Proc Natl Acad Sci U S A 2021; 118:2016363118. [PMID: 33883277 DOI: 10.1073/pnas.2016363118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The position of recombination events established along chromosomes in early prophase I and the chromosome remodeling that takes place in late prophase I are intrinsically linked steps of meiosis that need to be tightly regulated to ensure accurate chromosome segregation and haploid gamete formation. Here, we show that RAD-51 foci, which form at the sites of programmed meiotic DNA double-strand breaks (DSBs), exhibit a biased distribution toward off-centered positions along the chromosomes in wild-type Caenorhabditis elegans, and we identify two meiotic roles for chromatin-associated protein HIM-17 that ensure normal chromosome remodeling in late prophase I. During early prophase I, HIM-17 regulates the distribution of DSB-dependent RAD-51 foci and crossovers on chromosomes, which is critical for the formation of distinct chromosome subdomains (short and long arms of the bivalents) later during chromosome remodeling. During late prophase I, HIM-17 promotes the normal expression and localization of protein phosphatases GSP-1/2 to the surface of the bivalent chromosomes and may promote GSP-1 phosphorylation, thereby antagonizing Aurora B kinase AIR-2 loading on the long arms and preventing premature loss of sister chromatid cohesion. We propose that HIM-17 plays distinct roles at different stages during meiotic progression that converge to promote normal chromosome remodeling and accurate chromosome segregation.
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7
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Hu C, Feng P, Yang Q, Xiao L. Clinical and Neurobiological Aspects of TAO Kinase Family in Neurodevelopmental Disorders. Front Mol Neurosci 2021; 14:655037. [PMID: 33867937 PMCID: PMC8044823 DOI: 10.3389/fnmol.2021.655037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/04/2021] [Indexed: 12/20/2022] Open
Abstract
Despite the complexity of neurodevelopmental disorders (NDDs), from their genotype to phenotype, in the last few decades substantial progress has been made in understanding their pathophysiology. Recent accumulating evidence shows the relevance of genetic variants in thousand and one (TAO) kinases as major contributors to several NDDs. Although it is well-known that TAO kinases are a highly conserved family of STE20 kinase and play important roles in multiple biological processes, the emerging roles of TAO kinases in neurodevelopment and NDDs have yet to be intensively discussed. In this review article, we summarize the potential roles of the TAO kinases based on structural and biochemical analyses, present the genetic data from clinical investigations, and assess the mechanistic link between the mutations of TAO kinases, neuropathology, and behavioral impairment in NDDs. We then offer potential perspectives from basic research to clinical therapies, which may contribute to fully understanding how TAO kinases are involved in NDDs.
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Affiliation(s)
- Chun Hu
- Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, South China Normal University, Guangzhou, China.,Institute for Brain Research and Rehabilitation, South China Normal University, Guangzhou, China
| | - Pan Feng
- Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, South China Normal University, Guangzhou, China.,Institute for Brain Research and Rehabilitation, South China Normal University, Guangzhou, China
| | - Qian Yang
- Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, South China Normal University, Guangzhou, China.,Institute for Brain Research and Rehabilitation, South China Normal University, Guangzhou, China
| | - Lin Xiao
- Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, South China Normal University, Guangzhou, China.,Institute for Brain Research and Rehabilitation, South China Normal University, Guangzhou, China
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8
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Achache H, Laurent L, Hecker-Mimoun Y, Ishtayeh H, Rappaport Y, Kroizer E, Colaiácovo MP, Tzur YB. Progression of Meiosis Is Coordinated by the Level and Location of MAPK Activation Via OGR-2 in Caenorhabditis elegans. Genetics 2019; 212:213-229. [PMID: 30867196 PMCID: PMC6499523 DOI: 10.1534/genetics.119.302080] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 03/07/2019] [Indexed: 02/07/2023] Open
Abstract
During meiosis, a series of evolutionarily conserved events allow for reductional chromosome division, which is required for sexual reproduction. Although individual meiotic processes have been extensively studied, we currently know far less about how meiosis is regulated and coordinated. In the Caenorhabditis elegans gonad, mitogen-activated protein kinase (MAPK) signaling drives oogenesis while undergoing spatial activation and deactivation waves. However, it is currently unclear how MAPK activation is governed and how it facilitates the progression of oogenesis. Here, we show that the oocyte and germline-related 2 (ogr-2) gene affects proper progression of oogenesis. Complete deletion of ogr-2 results in delayed meiotic entry and late spatial onset of double-strand break repair. Elevated levels of apoptosis are observed in this mutant, independent of the meiotic canonical checkpoints; however, they are dependent on the MAPK terminal member MPK-1/ERK. MPK-1 activation is elevated in diplotene in ogr-2 mutants and its aberrant spatial activation correlates with stages where meiotic progression defects are evident. Deletion of ogr-2 significantly reduces the expression of lip-1, a phosphatase reported to repress MPK-1, which is consistent with OGR-2 localization at chromatin in germ cells. We suggest that OGR-2 modulates the expression of lip-1 to promote the timely progression of meiosis through MPK-1 spatial deactivation.
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Affiliation(s)
- Hanna Achache
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Lévana Laurent
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Yaël Hecker-Mimoun
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Hasan Ishtayeh
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Yisrael Rappaport
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Eitan Kroizer
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | | | - Yonatan B Tzur
- Department of Genetics, Institute of Life Sciences, Hebrew University, Givat-Ram, Jerusalem 91904, Israel
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Raiders SA, Eastwood MD, Bacher M, Priess JR. Binucleate germ cells in Caenorhabditis elegans are removed by physiological apoptosis. PLoS Genet 2018; 14:e1007417. [PMID: 30024879 PMCID: PMC6053125 DOI: 10.1371/journal.pgen.1007417] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 05/15/2018] [Indexed: 12/27/2022] Open
Abstract
Cell death plays a major role during C. elegans oogenesis, where over half of the oogenic germ cells die in a process termed physiological apoptosis. How germ cells are selected for physiological apoptosis, or instead become oocytes, is not understood. Most oocytes produce viable embryos when apoptosis is blocked, suggesting that physiological apoptosis does not function to cull defective germ cells. Instead, cells targeted for apoptosis may function as nurse cells; the germline is syncytial, and all germ cells appear to contribute cytoplasm to developing oocytes. C. elegans has been a leading model for the genetics and molecular biology of apoptosis and phagocytosis, but comparatively few studies have examined the cell biology of apoptotic cells. We used live imaging to identify and examine pre-apoptotic germ cells in the adult gonad. After initiating apoptosis, germ cells selectively export their mitochondria into the shared pool of syncytial cytoplasm; this transport appears to use the microtubule motor kinesin. The apoptotic cells then shrink as they expel most of their remaining cytoplasm, and close off from the syncytium. Shortly thereafter the apoptotic cells restructure their microtubule and actin cytoskeletons, possibly to maintain cell integrity; the microtubules form a novel, cortical array of stabilized microtubules, and actin and cofilin organize into giant cofilin-actin rods. We discovered that some apoptotic germ cells are binucleate; the binucleate germ cells can develop into binucleate oocytes in apoptosis-defective strains, and appear capable of producing triploid offspring. Our results suggest that the nuclear layer of the germline syncytium becomes folded during mitosis and growth, and that binucleate cells arise as the layer unfolds or everts; all of the binucleate cells are subsequently removed by apoptosis. These results show that physiological apoptosis targets at least two distinct populations of germ cells, and that the apoptosis machinery efficiently recognizes cells with two nuclei. Many germ cells die by apoptosis during the development of animal oocytes, including more than half of all germ cells in the model system C. elegans. How individual germ cells are selected for apoptosis, or survival, is not known. Here we study the cell biology of apoptosis. The C. elegans gonad is a syncytium, with nearly 1000 germ “cells” connected to a shared, core cytoplasm. Once apoptosis is initiated, germ cells selectively transport their mitochondria into the gonad core, apparently using the microtubule motor protein kinesin. The apoptotic cells next constrict, expelling most of their remaining cytoplasm into the core, and close off from the gonad core. The microtubule and actin cytoskeletons are remodeled and stabilized, presumably to maintain the integrity of the dying cell. The apoptotic cells form giant cofilin-actin rods, similar to rods described in stressed cultured cells and in human myopathies and neuropathies such as Alzheimer’s and Huntington’s disease. We show that some germ cells are binucleate; these cells appear to form during germline morphogenesis, and are removed by apoptosis. These results demonstrate heterogeneity between oogenic germ cells, and show that the apoptosis machinery efficiently recognizes and removes cells with two nuclei.
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Affiliation(s)
- Stephan A. Raiders
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Michael D. Eastwood
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Meghan Bacher
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - James R. Priess
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Molecular and Cellular Biology Program, University of Washington, Seattle, Washington, United States of America
- Department of Biology, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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10
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Reichman R, Shi Z, Malone R, Smolikove S. Mitotic and Meiotic Functions for the SUMOylation Pathway in the Caenorhabditis elegans Germline. Genetics 2018; 208:1421-1441. [PMID: 29472245 PMCID: PMC5887140 DOI: 10.1534/genetics.118.300787] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 02/19/2018] [Indexed: 02/07/2023] Open
Abstract
Meiosis is a highly regulated process, partly due to the need to break and then repair DNA as part of the meiotic program. Post-translational modifications are widely used during meiotic events to regulate steps such as protein complex formation, checkpoint activation, and protein attenuation. In this paper, we investigate how proteins that are obligatory components of the SUMO (small ubiquitin-like modifier) pathway, one such post-translational modification, affect the Caenorhabditis elegans germline. We show that UBC-9, the E2 conjugation enzyme, and the C. elegans homolog of SUMO, SMO-1, localize to germline nuclei throughout prophase I. Mutant analysis of smo-1 and ubc-9 revealed increased recombination intermediates throughout the germline, originating during the mitotic divisions. SUMOylation mutants also showed late meiotic defects including defects in the restructuring of oocyte bivalents and endomitotic oocytes. Increased rates of noninterfering crossovers were observed in ubc-9 heterozygotes, even though interfering crossovers were unaffected. We have also identified a physical interaction between UBC-9 and DNA repair protein MRE-11 ubc-9 and mre-11 null mutants exhibited similar phenotypes at germline mitotic nuclei and were synthetically sick. These phenotypes and genetic interactions were specific to MRE-11 null mutants as opposed to RAD-50 or resection-defective MRE-11 We propose that the SUMOylation pathway acts redundantly with MRE-11, and in this process MRE-11 likely plays a structural role.
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Affiliation(s)
- Rachel Reichman
- Department of Biology, The University of Iowa, Iowa City, Iowa 52242
| | - Zhuoyue Shi
- Department of Biology, The University of Iowa, Iowa City, Iowa 52242
| | - Robert Malone
- Department of Biology, The University of Iowa, Iowa City, Iowa 52242
| | - Sarit Smolikove
- Department of Biology, The University of Iowa, Iowa City, Iowa 52242
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11
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Reichman R, Alleva B, Smolikove S. Prophase I: Preparing Chromosomes for Segregation in the Developing Oocyte. Results Probl Cell Differ 2017; 59:125-173. [PMID: 28247048 DOI: 10.1007/978-3-319-44820-6_5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Formation of an oocyte involves a specialized cell division termed meiosis. In meiotic prophase I (the initial stage of meiosis), chromosomes undergo elaborate events to ensure the proper segregation of their chromosomes into gametes. These events include processes leading to the formation of a crossover that, along with sister chromatid cohesion, forms the physical link between homologous chromosomes. Crossovers are formed as an outcome of recombination. This process initiates with programmed double-strand breaks that are repaired through the use of homologous chromosomes as a repair template. The accurate repair to form crossovers takes place in the context of the synaptonemal complex, a protein complex that links homologous chromosomes in meiotic prophase I. To allow proper execution of meiotic prophase I events, signaling processes connect different steps in recombination and synapsis. The events occurring in meiotic prophase I are a prerequisite for proper chromosome segregation in the meiotic divisions. When these processes go awry, chromosomes missegregate. These meiotic errors are thought to increase with aging and may contribute to the increase in aneuploidy observed in advanced maternal age female oocytes.
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Affiliation(s)
- Rachel Reichman
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Benjamin Alleva
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Sarit Smolikove
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA.
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