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Pesquisa : G04.144.220.220.687.444 [Categoria DeCS]
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  1 / 332 MEDLINE  
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[PMID]:28708824
[Au] Autor:Crichton JH; Playfoot CJ; MacLennan M; Read D; Cooke HJ; Adams IR
[Ad] Endereço:MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom.
[Ti] Título:Tex19.1 promotes Spo11-dependent meiotic recombination in mouse spermatocytes.
[So] Source:PLoS Genet;13(7):e1006904, 2017 Jul.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Meiosis relies on the SPO11 endonuclease to generate the recombinogenic DNA double strand breaks (DSBs) required for homologous chromosome synapsis and segregation. The number of meiotic DSBs needs to be sufficient to allow chromosomes to search for and find their homologs, but not excessive to the point of causing genome instability. Here we report that the mammal-specific gene Tex19.1 promotes Spo11-dependent recombination in mouse spermatocytes. We show that the chromosome asynapsis previously reported in Tex19.1-/- spermatocytes is preceded by reduced numbers of recombination foci in leptotene and zygotene. Tex19.1 is required for normal levels of early Spo11-dependent recombination foci during leptotene, but not for upstream events such as MEI4 foci formation or accumulation of H3K4me3 at recombination hotspots. Furthermore, we show that mice carrying mutations in Ubr2, which encodes an E3 ubiquitin ligase that interacts with TEX19.1, phenocopy the Tex19.1-/- recombination defects. These data suggest that Tex19.1 and Ubr2 are required for mouse spermatocytes to accumulate sufficient Spo11-dependent recombination to ensure that the homology search is consistently successful, and reveal a hitherto unknown genetic pathway promoting meiotic recombination in mammals.
[Mh] Termos MeSH primário: Endodesoxirribonucleases/metabolismo
Meiose/genética
Proteínas Nucleares/metabolismo
Espermatócitos/metabolismo
Ubiquitina-Proteína Ligases/metabolismo
[Mh] Termos MeSH secundário: Animais
Pareamento Cromossômico
Cromossomos de Mamíferos/genética
Cromossomos de Mamíferos/metabolismo
Endodesoxirribonucleases/genética
Masculino
Prófase Meiótica I/genética
Camundongos
Camundongos Endogâmicos C57BL
Proteínas Nucleares/genética
Regiões Promotoras Genéticas
Recombinação Genética
Ubiquitina-Proteína Ligases/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nuclear Proteins); 0 (Tex19 protein, mouse); EC 2.3.2.27 (UBR2 protein, mouse); EC 2.3.2.27 (Ubiquitin-Protein Ligases); EC 3.1.- (Endodeoxyribonucleases); EC 3.1.- (meiotic recombination protein SPO11)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170715
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006904


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[PMID]:28552778
[Au] Autor:Liu KH; Sun XF; Feng YZ; Cheng SF; Li B; Li YP; Shen W; Li L
[Ad] Endereço:College of Animal Science and Technology, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao 266109, China.
[Ti] Título:The impact of Zearalenone on the meiotic progression and primordial follicle assembly during early oogenesis.
[So] Source:Toxicol Appl Pharmacol;329:9-17, 2017 Aug 15.
[Is] ISSN:1096-0333
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Zearalenone (ZEA) is a mycotoxin produced by fusarium graminearum. It can cause abnormal reproductive function by acting as an environmental estrogen. Research has traditionally focused on acute and chronic injury on mammalian reproductive capacity after ZEA treatment. Little research has been done studying the effects of ZEA exposure on early oogenesis. In this study, we investigate the effects of ZEA exposure on meiotic entry, DNA double-strand breaks (DSBs), and primordial follicle assembly during murine early oogenesis. The results show that ZEA exposure significantly decreased the percentage of diplotene stage germ cells, and made more germ cells remain at zygotene or pachytene stages. Moreover, the mRNA expression level of meiosis-related genes was significantly reduced after ZEA treatment. ZEA exposure significantly increased DNA-DSBs at the diplotene stage. Meanwhile, DNA damage repair genes such as RAD51 and BRCA1 were activated. Furthermore, maternal exposure to ZEA significantly decreased the number of primordial follicles in newborn mouse ovaries. In conclusion, ZEA exposure impairs mouse female germ cell meiotic progression, DNA-DSBs, and primordial follicle assembly.
[Mh] Termos MeSH primário: Disruptores Endócrinos/toxicidade
Estrogênios não Esteroides/toxicidade
Meiose/efeitos dos fármacos
Oogênese/efeitos dos fármacos
Folículo Ovariano/efeitos dos fármacos
Óvulo/efeitos dos fármacos
Zearalenona/toxicidade
[Mh] Termos MeSH secundário: Animais
Quebras de DNA de Cadeia Dupla
Reparo do DNA/efeitos dos fármacos
Feminino
Prófase Meiótica I/efeitos dos fármacos
Camundongos
Folículo Ovariano/metabolismo
Folículo Ovariano/patologia
Óvulo/metabolismo
Óvulo/patologia
Gravidez
Rad51 Recombinase/metabolismo
Medição de Risco
Proteínas Supressoras de Tumor/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Brca1 protein, mouse); 0 (Endocrine Disruptors); 0 (Estrogens, Non-Steroidal); 0 (Tumor Suppressor Proteins); 5W827M159J (Zearalenone); EC 2.7.7.- (Rad51 Recombinase); EC 2.7.7.- (Rad51 protein, mouse)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170530
[St] Status:MEDLINE


  3 / 332 MEDLINE  
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[PMID]:28494440
[Au] Autor:Berrios S
[Ad] Endereço:Programa Genética Humana, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
[Ti] Título:Nuclear Architecture of Mouse Spermatocytes: Chromosome Topology, Heterochromatin, and Nucleolus.
[So] Source:Cytogenet Genome Res;151(2):61-71, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:The nuclear organization of spermatocytes in meiotic prophase I is primarily determined by the synaptic organization of the bivalents that are bound by their telomeres to the nuclear envelope and described as arc-shaped trajectories through the 3D nuclear space. However, over this basic meiotic organization, a spermatocyte nuclear architecture arises that is based on higher-ordered patterns of spatial associations among chromosomal domains from different bivalents that are conditioned by the individual characteristics of chromosomes and the opportunity for interactions between their domains. Consequently, the nuclear architecture is species-specific and prone to modification by chromosomal rearrangements. This model is valid for the localization of any chromosomal domain in the meiotic prophase nucleus. However, constitutive heterochromatin plays a leading role in shaping nuclear territories. Thus, the nuclear localization of nucleoli depends on the position of NORs in nucleolar bivalents, but the association among nucleolar chromosomes mainly depends on the presence of constitutive heterochromatin that does not affect the expression of the ribosomal genes. Constitutive heterochromatin and nucleoli form complex nuclear territories whose distribution in the nuclear space is nonrandom, supporting the hypothesis regarding the existence of a species-specific nuclear architecture in first meiotic prophase spermatocytes.
[Mh] Termos MeSH primário: Nucléolo Celular/genética
Cromossomos
Heterocromatina
Espermatócitos/citologia
[Mh] Termos MeSH secundário: Animais
Nucléolo Celular/ultraestrutura
Heterocromatina/química
Heterocromatina/genética
Heterocromatina/metabolismo
Masculino
Prófase Meiótica I
Camundongos
Região Organizadora do Nucléolo
Espermatócitos/fisiologia
Espermatócitos/ultraestrutura
Telômero
Translocação Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Heterochromatin)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170512
[St] Status:MEDLINE
[do] DOI:10.1159/000460811


  4 / 332 MEDLINE  
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[PMID]:28410121
[Au] Autor:Tiwari M; Prasad S; Pandey AN; Premkumar KV; Tripathi A; Gupta A; Chetan DR; Yadav PK; Shrivastav TG; Chaube SK
[Ad] Endereço:Cell Physiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi-221005, U.P., India.
[Ti] Título:Nitric oxide signaling during meiotic cell cycle regulation in mammalian oocytes.
[So] Source:Front Biosci (Schol Ed);9:307-318, 2017 Jun 01.
[Is] ISSN:1945-0524
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:  Nitric oxide (NO) acts as a major signal molecules and modulate physiology of mammalian oocytes. Ovarian follicles generate large amount of NO through nitric oxide synthase (NOS) pathway to maintain diplotene arrest in preovulatory oocytes. Removal of oocytes from follicular microenvironment or follicular rupture during ovulation disrupt the flow of NO from granulosa cells to the oocyte that results a transient decrease of oocyte cytoplasmic NO level. Decreased NO level reduces cyclic nucleotides level by inactivating guanylyl cyclases directly or indirectly. The reduced cyclic nucleotides level modulate specific phosphorylation status of cyclin-dependent kinase 1 (Cdk1) and triggers cyclin B1 degradation. These changes result in maturation promoting factor (MPF) destabilization that finally triggers meiotic resumption from diplotene as well as metaphase-II (M-II) arrest in most of the mammalian species.
[Mh] Termos MeSH primário: Meiose/fisiologia
Óxido Nítrico/metabolismo
Oócitos/citologia
Oócitos/metabolismo
[Mh] Termos MeSH secundário: Animais
Feminino
Seres Humanos
Prófase Meiótica I/fisiologia
Transdução de Sinais
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
31C4KY9ESH (Nitric Oxide)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170602
[Lr] Data última revisão:
170602
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170415
[St] Status:MEDLINE


  5 / 332 MEDLINE  
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[PMID]:28247047
[Au] Autor:Arur S
[Ad] Endereço:Department of Genetics, UT M.D. Anderson Cancer Center, Houston, TX, USA. sarur@mdanderson.org.
[Ti] Título:Signaling-Mediated Regulation of Meiotic Prophase I and Transition During Oogenesis.
[So] Source:Results Probl Cell Differ;59:101-123, 2017.
[Is] ISSN:0080-1844
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Generation of healthy oocytes requires coordinated regulation of multiple cellular events and signaling pathways. Oocytes undergo a unique developmental growth and differentiation pattern interspersed with long periods of arrest. Oocytes from almost all species arrest in prophase I of oogenesis that allows for long period of growth and differentiation essential for normal oocyte development. Depending on species, oocytes that transit from prophase I to meiosis I also arrest at meiosis I for fairly long periods of time and then undergo a second arrest at meiosis II that is completed upon fertilization. While there are species-specific differences in C. elegans, D. melanogaster, and mammalian oocytes in stages of prophase I, meiosis I, or meiosis II arrest, in all cases cell signaling pathways coordinate the developmental events controlling oocyte growth and differentiation to regulate these crucial phases of transition. In particular, the ERK MAP kinase signaling pathway, cyclic AMP second messengers, and the cell cycle regulators CDK1/cyclin B are key signaling pathways that seem evolutionarily conserved in their control of oocyte growth and meiotic maturation across species. Here, I identify the common themes and differences in the regulation of key meiotic events during oocyte growth and maturation.
[Mh] Termos MeSH primário: Meiose/fisiologia
Oogênese/fisiologia
Transdução de Sinais/fisiologia
[Mh] Termos MeSH secundário: Animais
Feminino
Seres Humanos
Prófase Meiótica I/fisiologia
Oócitos/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; REVIEW
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170302
[St] Status:MEDLINE
[do] DOI:10.1007/978-3-319-44820-6_4


  6 / 332 MEDLINE  
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[PMID]:28247048
[Au] Autor:Reichman R; Alleva B; Smolikove S
[Ad] Endereço:Department of Biology, University of Iowa, Iowa City, IA, 52242, USA.
[Ti] Título:Prophase I: Preparing Chromosomes for Segregation in the Developing Oocyte.
[So] Source:Results Probl Cell Differ;59:125-173, 2017.
[Is] ISSN:0080-1844
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo: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.
[Mh] Termos MeSH primário: Segregação de Cromossomos/fisiologia
Prófase Meiótica I/fisiologia
Oócitos/citologia
Oogênese/fisiologia
[Mh] Termos MeSH secundário: Animais
Feminino
Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170302
[St] Status:MEDLINE
[do] DOI:10.1007/978-3-319-44820-6_5


  7 / 332 MEDLINE  
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[PMID]:27738269
[Au] Autor:Pandey N; Giri S; Das S; Upadhaya P
[Ad] Endereço:Molecular Cytogenetic Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India.
[Ti] Título:Radiofrequency radiation (900 MHz)-induced DNA damage and cell cycle arrest in testicular germ cells in swiss albino mice.
[So] Source:Toxicol Ind Health;33(4):373-384, 2017 Apr.
[Is] ISSN:1477-0393
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Even though there are contradictory reports regarding the cellular and molecular changes induced by mobile phone emitted radiofrequency radiation (RFR), the possibility of any biological effect cannot be ruled out. In view of a widespread and extensive use of mobile phones, this study evaluates alterations in male germ cell transformation kinetics following RFR exposure and after recovery. Swiss albino mice were exposed to RFR (900 MHz) for 4 h and 8 h duration per day for 35 days. One group of animals was terminated after the exposure period, while others were kept for an additional 35 days post-exposure. RFR exposure caused depolarization of mitochondrial membranes resulting in destabilized cellular redox homeostasis. Statistically significant increases in the damage index in germ cells and sperm head defects were noted in RFR-exposed animals. Flow cytometric estimation of germ cell subtypes in mice testis revealed 2.5-fold increases in spermatogonial populations with significant decreases in spermatids. Almost fourfold reduction in spermatogonia to spermatid turnover (1C:2C) and three times reduction in primary spermatocyte to spermatid turnover (1C:4C) was found indicating arrest in the premeiotic stage of spermatogenesis, which resulted in loss of post-meiotic germ cells apparent from testis histology and low sperm count in RFR-exposed animals. Histological alterations such as sloughing of immature germ cells into the seminiferous tubule lumen, epithelium depletion and maturation arrest were also observed. However, all these changes showed recovery to varied degrees following the post-exposure period indicating that the adverse effects of RFR on mice germ cells are detrimental but reversible. To conclude, RFR exposure-induced oxidative stress causes DNA damage in germ cells, which alters cell cycle progression leading to low sperm count in mice.
[Mh] Termos MeSH primário: Telefone Celular
Dano ao DNA/efeitos da radiação
Oligospermia/etiologia
Lesões Experimentais por Radiação/etiologia
Ondas de Rádio/efeitos adversos
Espermatogênese/efeitos da radiação
Espermatozoides/efeitos da radiação
[Mh] Termos MeSH secundário: Animais
Ensaio Cometa
Relação Dose-Resposta à Radiação
Cinética
Masculino
Prófase Meiótica I/efeitos da radiação
Potencial da Membrana Mitocondrial/efeitos da radiação
Camundongos
Oligospermia/patologia
Estresse Oxidativo/efeitos da radiação
Lesões Experimentais por Radiação/patologia
Túbulos Seminíferos/patologia
Túbulos Seminíferos/efeitos da radiação
Cabeça do Espermatozoide/patologia
Cabeça do Espermatozoide/efeitos da radiação
Espermatogônias/patologia
Espermatogônias/efeitos da radiação
Espermatozoides/patologia
Testes de Toxicidade Subcrônica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161015
[St] Status:MEDLINE
[do] DOI:10.1177/0748233716671206


  8 / 332 MEDLINE  
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[PMID]:27699653
[Au] Autor:Ishiguro KI; Monti M; Akiyama T; Kimura H; Chikazawa-Nohtomi N; Sakota M; Sato S; Redi CA; Ko SB; Ko MS
[Ad] Endereço:Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan.
[Ti] Título:Zscan4 is expressed specifically during late meiotic prophase in both spermatogenesis and oogenesis.
[So] Source:In Vitro Cell Dev Biol Anim;53(2):167-178, 2017 Feb.
[Is] ISSN:1543-706X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Mouse zinc finger and SCAN domain containing 4 (Zscan4) proteins, which are encoded by multiple copies of Zscan4 genes, are expressed specifically in preimplantation embryos in vivo and embryonic stem (ES) cells in vitro. However, the expression patterns of mouse Zscan4 in vivo have been largely elusive. Here, we show that Zscan4 proteins are expressed in adult ovaries and testes. In ovaries, Zscan4 proteins were detected in germinal vesicle (GV) stage oocytes in antral follicles, indicating that Zscan4 genes are activated during the diplotene/dictyate stage in meiotic prophase I. Remarkably, Zscan4 showed different spatial localization patterns between two distinct GV oocytes, which can be distinguished by global chromatin organization-surrounded nucleolus (SN) and non-surrounded nucleolus (NSN). These spatiotemporal differences in Zscan4 localizations correlated with the transition of RNA polymerase II-mediated transcriptional status during GV oocyte maturation. In testes, Zscan4 proteins were detected in spermatocytes at late pachytene/diplotene stages and in Sertoli cells. These results suggest that Zscan4 may play critical roles during late meiotic prophase in both males and females.
[Mh] Termos MeSH primário: Proteínas Cromossômicas não Histona/metabolismo
Prófase Meiótica I
Oogênese
Espermatogênese
Fatores de Transcrição/metabolismo
[Mh] Termos MeSH secundário: Animais
Blastocisto/citologia
Blastocisto/metabolismo
Proteínas Cromossômicas não Histona/genética
Feminino
Masculino
Prófase Meiótica I/genética
Camundongos Endogâmicos C57BL
Oogênese/genética
Folículo Ovariano/citologia
Folículo Ovariano/metabolismo
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Células de Sertoli/citologia
Células de Sertoli/metabolismo
Espermatogênese/genética
Espermatozoides/citologia
Espermatozoides/metabolismo
Testículo/citologia
Testículo/metabolismo
Fatores de Transcrição/genética
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromosomal Proteins, Non-Histone); 0 (RNA, Messenger); 0 (Transcription Factors)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170310
[Lr] Data última revisão:
170310
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161005
[St] Status:MEDLINE
[do] DOI:10.1007/s11626-016-0096-z


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[PMID]:27686466
[Au] Autor:Tchórzewska D; Derylo K; Winiarczyk K
[Ad] Endereço:Department of Plant Anatomy and Cytology, Maria Curie-Sklodowska University, Akademicka 19 Street, 20-033, Lublin, Poland. dorota.tchorzewska@poczta.umcs.lublin.pl.
[Ti] Título:Cytological and biophysical comparative analysis of cell structures at the microsporogenesis stage in sterile and fertile Allium species.
[So] Source:Planta;245(1):137-150, 2017 Jan.
[Is] ISSN:1432-2048
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:MAIN CONCLUSION: Using a live-cell-imaging approach and autofluorescence-spectral imaging, we showed quantitative/qualitative fluctuations of chemical compounds within the meiocyte callose wall, providing insight into the molecular basis of male sterility in plants from the genus Allium. Allium sativum (garlic) is one of the plant species exhibiting male sterility, and the molecular background of this phenomenon has never been thoroughly described. This study presents comparative analyses of meiotically dividing cells, which revealed inhibition at the different microsporogenesis stages in male-sterile A. sativum plants (cultivars Harnas and Arkus) and sterile A. ampeloprasum var. ampeloprasum (GHG-L), which is phylogenetically related to garlic. Fertile species A. ampeloprasum (leek) was used as the control material, because leek is closely related to both garlic and GHG-L. To shed more light on the molecular basis of these disturbances, autofluorescence-spectral imaging of live cells was used for the assessment of the biophysical/biochemical differences in the callose wall, pollen grain sporoderm, and the tapetum in the sterile species, in comparison with the fertile leek. The use of techniques for live-cell imaging (autofluorescence-spectral imaging) allowed the observation of quantitative/qualitative fluctuations of autofluorescent chemical compounds within the meiocyte callose wall. The biophysical characterisation of the metabolic disturbances in the callose wall provides insight into the molecular basis of male sterility in A. sativum. In addition, using this method, it was possible for the first time, to determine precisely (on the basis of fluctuations of autofluorescence compounds) the meiosis stage in which normal microsporogenesis is disturbed, which was not visible using light microscopy.
[Mh] Termos MeSH primário: Fenômenos Biofísicos
Gametogênese Vegetal
Alho/citologia
Alho/fisiologia
Infertilidade das Plantas
[Mh] Termos MeSH secundário: Prófase Meiótica I
Microscopia Confocal
Pólen/citologia
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170424
[Lr] Data última revisão:
170424
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161001
[St] Status:MEDLINE
[do] DOI:10.1007/s00425-016-2597-0


  10 / 332 MEDLINE  
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[PMID]:27662514
[Au] Autor:Gupta A; Tiwari M; Prasad S; Chaube SK
[Ad] Endereço:Cell Physiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
[Ti] Título:Role of Cyclic Nucleotide Phosphodiesterases During Meiotic Resumption From Diplotene Arrest in Mammalian Oocytes.
[So] Source:J Cell Biochem;118(3):446-452, 2017 Mar.
[Is] ISSN:1097-4644
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cyclic nucleotide phosphodiesterases (PDEs) are group of enzymes that hydrolyze cyclic nucleotides in wide variety of cell types including encircling granulosa cells as well as associated oocytes. One group of PDEs are located in encircling granulosa cells and another group get expressed in the oocyte, while few other PDEs are expressed in both compartments. The PDE1A, PDE4D, PDE5A, PDE8A, and PDE8B are granulosa cell specific PDEs that hydrolyze adenosine 3',5'-cyclic monophosphate (cAMP) as well as guanosine 3',5'-cyclic monophosphate (cGMP) with different affinities. PDE3A, PDE8A as well as PDE9A are expressed in oocyte and specifically responsible for the cyclic nucleotide hydrolysis in the oocyte itself. Few other PDEs such as PDE7B, PDE10A, and PDE11A are either detected in granulosa cells or oocytes. Activation of these PDEs either in encircling granulosa cells or in oocyte directly or indirectly reduces intraoocyte cAMP level. Reduction of intraoocyte cAMP level modulates phosphorylation status of cyclin-dependent kinase 1 (Cdk1) and triggers cyclin B1 degradation that destabilizes maturation promoting factor (MPF) and/or increases Cdk1 activity. The destabilized MPF and/or increased Cdk1 activity leads to resumption of meiosis, which initiates the achievement of meiotic competency in preovulatory follicles of several mammalian species. Use of specific PDEs inhibitors block cyclic nucleotides hydrolysis that results in increase of intraoocyte cyclic nucleotides level, which leads to maintenance of meiotic arrest at diplotene stage in vivo as well as in vitro. Thus, cyclic nucleotide PDEs play important role in the achievement of meiotic competency by reducing intraoocyte cyclic nucleotides level in mammalian oocytes. J. Cell. Biochem. 118: 446-452, 2017. © 2016 Wiley Periodicals, Inc.
[Mh] Termos MeSH primário: Pontos de Checagem do Ciclo Celular/fisiologia
AMP Cíclico/metabolismo
GMP Cíclico/metabolismo
Prófase Meiótica I/fisiologia
Oócitos/metabolismo
[Mh] Termos MeSH secundário: Animais
Feminino
Seres Humanos
Oócitos/citologia
Diester Fosfórico Hidrolases
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
E0399OZS9N (Cyclic AMP); EC 3.1.4.- (Phosphoric Diester Hydrolases); H2D2X058MU (Cyclic GMP)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160924
[St] Status:MEDLINE
[do] DOI:10.1002/jcb.25748



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