scholarly journals Regulation of Meiotic Prophase One in Mammalian Oocytes

2021 ◽  
Vol 9 ◽  
Author(s):  
Xiaoyi Wang ◽  
Melissa E. Pepling
Keyword(s):  
Luteinizing Hormone ◽  
Signaling Pathways ◽  
Chromosome Segregation ◽  
Fetal Development ◽  
Meiotic Prophase ◽  
Genetic Material ◽  
Sperm Nucleus ◽  
Meiotic Progression ◽  
And Control ◽  
Late Diplotene

In female mammals, meiotic prophase one begins during fetal development. Oocytes transition through the prophase one substages consisting of leptotene, zygotene, and pachytene, and are finally arrested at the diplotene substage, for months in mice and years in humans. After puberty, luteinizing hormone induces ovulation and meiotic resumption in a cohort of oocytes, driving the progression from meiotic prophase one to metaphase two. If fertilization occurs, the oocyte completes meiosis two followed by fusion with the sperm nucleus and preparation for zygotic divisions; otherwise, it is passed into the uterus and degenerates. Specifically in the mouse, oocytes enter meiosis at 13.5 days post coitum. As meiotic prophase one proceeds, chromosomes find their homologous partner, synapse, exchange genetic material between homologs and then begin to separate, remaining connected at recombination sites. At postnatal day 5, most of the oocytes have reached the late diplotene (or dictyate) substage of prophase one where they remain arrested until ovulation. This review focuses on events and mechanisms controlling the progression through meiotic prophase one, which include recombination, synapsis and control by signaling pathways. These events are prerequisites for proper chromosome segregation in meiotic divisions; and if they go awry, chromosomes mis-segregate resulting in aneuploidy. Therefore, elucidating the mechanisms regulating meiotic progression is important to provide a foundation for developing improved treatments of female infertility.

scholarly journals Spatial and temporal control of targeting Polo-like kinase during meiotic prophase

2020 ◽  
Vol 219 (11) ◽  
Author(s):  
James N. Brandt ◽  
Katarzyna A. Hussey ◽  
Yumi Kim
Keyword(s):  
Chromosome Segregation ◽  
Meiotic Prophase ◽  
Meiotic Chromosome ◽  
Holocentric Chromosomes ◽  
Cyclin Dependent Kinase ◽  
Chromosome Dynamics ◽  
C Elegans ◽  
Meiotic Progression ◽  
Crossover Site ◽  
Meiosis I

Polo-like kinases (PLKs) play widely conserved roles in orchestrating meiotic chromosome dynamics. However, how PLKs are targeted to distinct subcellular localizations during meiotic progression remains poorly understood. Here, we demonstrate that the cyclin-dependent kinase CDK-1 primes the recruitment of PLK-2 to the synaptonemal complex (SC) through phosphorylation of SYP-1 in C. elegans. SYP-1 phosphorylation by CDK-1 occurs just before meiotic onset. However, PLK-2 docking to the SC is prevented by the nucleoplasmic HAL-2/3 complex until crossover designation, which constrains PLK-2 to special chromosomal regions known as pairing centers to ensure proper homologue pairing and synapsis. PLK-2 is targeted to crossover sites primed by CDK-1 and spreads along the SC by reinforcing SYP-1 phosphorylation on one side of each crossover only when threshold levels of crossovers are generated. Thus, the integration of chromosome-autonomous signaling and a nucleus-wide crossover-counting mechanism partitions holocentric chromosomes relative to the crossover site, which ultimately defines the pattern of chromosome segregation during meiosis I.

The Protective Effects of Green Tea Catechins in the Management of Neurodegenerative Diseases: A Review

2019 ◽  
Vol 16 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Tahereh Farkhondeh ◽  
Hanieh Shaterzadeh Yazdi ◽  
Saeed Samarghandian
Keyword(s):  
Neurodegenerative Diseases ◽  
Signaling Pathways ◽  
Green Tea ◽  
Molecular Mechanisms ◽  
Main Role ◽  
Related Factor ◽  
Protective Effects ◽  
Tea Catechins ◽  
Green Tea Catechins ◽  
And Control

Background: The therapeutic strategies to manage neurodegenerative diseases remain limited and it is necessary to discover new agents for their prevention and control. Oxidative stress and inflammation play a main role in the pathogenesis of neurodegenerative diseases. The aim of this study is to review the effects of green tea catechins against the Neurodegenerative Diseases. Methods: In this study, we extensively reviewed all articles on the terms of Green tea, catechins, CNS disorders, and different diseases in PubMed, Science Direct, Scopus, and Google Scholar databases between the years 1990 and 2017. Results: The present study found that catechins, the major flavonoids in green tea, are powerful antioxidants and radical scavengers which possess the potential roles in the management of neurodegenerative diseases. Catechins modulate the cellular and molecular mechanisms through the inflammation-related NF-&amp;#954;B and the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Conclusion: The findings of the present review shows catechins could be effective against neurodegenerative diseases due to their antioxidation and anti-inflammation effects and the involved biochemical pathways including Nrf2 and NF-kB signaling pathways.<P&gt;

EFFECT OF CORTISOL OR ADRENOCORTICOTROPHIN ON RELEASE OF LUTEINIZING HORMONE INDUCED BY LUTEINIZING HORMONE RELEASING HORMONE IN THE DAIRY HEIFER

1982 ◽  
Vol 92 (1) ◽  
pp. 141-146 ◽  
Author(s):  
R. L. MATTERI ◽  
G. P. MOBERG
Keyword(s):  
Luteinizing Hormone ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Dairy Heifers ◽  
Significant Difference ◽  
Significant Depression ◽  
Lh Rh ◽  
Lh Releasing Hormone ◽  
And Control ◽  
Slight Depression

During treatment with cortisol or ACTH, dairy heifers were given two doses of LH releasing hormone (LH-RH) spaced 1·5 h apart. Serum concentrations of cortisol and LH were monitored during each treatment. Treatment with both ACTH and cortisol raised plasma cortisol levels above the respective saline controls (P<0·001). Neither treatment affected basal LH concentrations. A slight depression in LH response was seen in the cortisol-treated animals after the first LH-RH injection, as shown by a statistically significant depression at three of the sample times. There was no significant difference between treated and control LH values after the second LH-RH administration. Treatment with ACTH resulted in significantly reduced LH values at all sample times after both injections of LH-RH.

scholarly journals Proanthocyanidins against Oxidative Stress: From Molecular Mechanisms to Clinical Applications

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Lingyu Yang ◽  
Dehai Xian ◽  
Xia Xiong ◽  
Rui Lai ◽  
Jing Song ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Metabolic Diseases ◽  
Low Cost ◽  
Natural Agents ◽  
Molecular Damage ◽  
And Control

Proanthocyanidins (PCs) are naturally occurring polyphenolic compounds abundant in many vegetables, plant skins (rind/bark), seeds, flowers, fruits, and nuts. Numerousin vitroandin vivostudies have demonstrated myriad effects potentially beneficial to human health, such as antioxidation, anti-inflammation, immunomodulation, DNA repair, and antitumor activity. Accumulation of prooxidants such as reactive oxygen species (ROS) exceeding cellular antioxidant capacity results in oxidative stress (OS), which can damage macromolecules (DNA, lipids, and proteins), organelles (membranes and mitochondria), and whole tissues. OS is implicated in the pathogenesis and exacerbation of many cardiovascular, neurodegenerative, dermatological, and metabolic diseases, both through direct molecular damage and secondary activation of stress-associated signaling pathways. PCs are promising natural agents to safely prevent acute damage and control chronic diseases at relatively low cost. In this review, we summarize the molecules and signaling pathways involved in OS and the corresponding therapeutic mechanisms of PCs.

Genetic analysis of uniformity of rapeseed varieties and hybrids and control of inheritance of genetic material of parental forms by hybrids

2010 ◽  
Vol 36 (6) ◽  
pp. 408-412
Author(s):  
T. G. Satina ◽  
Yu. V. Aniskina ◽  
V. V. Karpachev ◽  
I. A. Shilov ◽  
P. N. Kharchenko
Keyword(s):  
Genetic Analysis ◽  
Genetic Material ◽  
And Control

scholarly journals Association between Luteinizing Hormone/Choriogonadotropin Receptor Ins18LQ Gene Polymorphism and Polycystic Ovary Syndrome

2020 ◽  
Vol 8 (A) ◽  
pp. 517-520
Author(s):  
Hilma Putri Lubis ◽  
Muhammad Fidel Ganis Siregar ◽  
Ichwanul Adenin ◽  
Binarwan Halim ◽  
Henry Salim Siregar ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Polycystic Ovary Syndrome ◽  
Gene Polymorphism ◽  
Polycystic Ovary ◽  
Control Group ◽  
Control Groups ◽  
Ovary Syndrome ◽  
Significant Difference ◽  
Pcos Group ◽  
And Control

BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders of women in the childbearing period. However, its pathophysiology is still unclear. Certain polymorphisms of the luteinizing hormone/choriogonadotropin receptor (LHCGR) genes may lead to changes in the bioactivity of this hormone. The important functional role of LHCGR in the metabolism of androgen and ovulation, the LHCGR gene variant, may be related to the risk of PCOS. AIM: The aim of this study was to evaluate the association between LHCGR Ins18LQ gene polymorphism and PCOS. METHODS: A case–control study was performed in women with PCOS and non-PCOS from May 2019 to October 2019 in HFC IVF Center. We included 50 women with PCOS and 50 healthy controls. Polymorphism of the LHCGR (ins18LQ) gene was genotyped using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: From this study, we found that there was no significant difference in the proportion of ages between the groups (p > 0.05). There were significant differences in the characteristics of body mass index, FSH level, LH level, and LH/FSH ratio between the PCOS and control groups (p < 0.05). We also found that the proportion of heterozygote variant non-ins/ins was higher in the PCOS group compared to the control group, but there was no significant difference between the polymorphisms of the non-ins and non-nonins variants between the PCOS and control groups (p = 0.269). The frequency of ins alleles was higher in the PCOS group compared to the control group. CONCLUSION: There was no significant association between LHCGR ins18LQ gene polymorphism and PCOS.

scholarly journals KERAGAMAN GENETIK MUTAN M-2 CABAI MERAH KERITING (Capsicum annuum L.) BERDASARKAN PENANDA RAPD

2020 ◽  
Vol 10 (2) ◽  
pp. 92
Author(s):  
Rosmaina Rosmaina ◽  
Dedi Mulyadi ◽  
Rita Elfianis ◽  
Zulfahmi Zulfahmi
Keyword(s):  
Capsicum Annuum ◽  
Gamma Ray ◽  
Rapd Analysis ◽  
Genetic Material ◽  
Polymorphic Loci ◽  
Capsicum Annuum L ◽  
Horticultural Plant ◽  
Dna Fragment ◽  
And Control ◽  
Selection Of

Chili is an important horticultural plant in Indonesia. This research aims to carry out RAPD analysis on Mutant M2 of chili pepper (Capsicum annuum L.). Six M2 genotypes of chili irradiated by gamma ray and control plants were amplified by 16 random primers. The amplification results of M2 chili with 16 primers produced 118 loci, with fragment sizes ranging from 150-2000 bp. The number of polymorphic loci was 96 loci and the percentage of polymorphic loci was 83.23%. The DNA fragment polymorphism produced in this research was relatively high and it showed that the gamma ray mutagen applied produced high chili genetic diversity. The value of genetic similarity between control plants and mutant plants ranged from 0.7474 to 0.4874. UPGMA dendogram classified seven genotypes tested into three groups, the first group consisted of mutants R2U6 and R2U17, the second group was mutants R1U14 and R1U17, and the third group was mutants R2U8, mutants R2U2 and control plants. The finding of this research can be used as a basic selection of genetic material for chili’s breeding in the future.

scholarly journals Increased Expression of Maturation Promoting Factor Components Speeds Up Meiosis in Oocytes from Aged Females

2018 ◽  
Vol 19 (9) ◽  
pp. 2841 ◽  
Author(s):  
Marketa Koncicka ◽  
Anna Tetkova ◽  
Denisa Jansova ◽  
Edgar Del Llano ◽  
Lenka Gahurova ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Maternal Age ◽  
Germ Line ◽  
Nuclear Lamina ◽  
Nuclear Envelope Breakdown ◽  
Meiotic Progression ◽  
Translational Activity ◽  
Female Germ Line ◽  
Mammalian Female ◽  
Meiosis I

The rate of chromosome segregation errors that emerge during meiosis I in the mammalian female germ line are known to increase with maternal age; however, little is known about the underlying molecular mechanism. The objective of this study was to analyze meiotic progression of mouse oocytes in relation to maternal age. Using the mouse as a model system, we analyzed the timing of nuclear envelope breakdown and the morphology of the nuclear lamina of oocytes obtained from young (2 months old) and aged females (12 months old). Oocytes obtained from older females display a significantly faster progression through meiosis I compared to the ones obtained from younger females. Furthermore, in oocytes from aged females, lamin A/C structures exhibit rapid phosphorylation and dissociation. Additionally, we also found an increased abundance of MPF components and increased translation of factors controlling translational activity in the oocytes of aged females. In conclusion, the elevated MPF activity observed in aged female oocytes affects precocious meiotic processes that can multifactorially contribute to chromosomal errors in meiosis I.

N6-methyladenosine modification modulate in the heat stress of sheep (Ovis aries)

2019 ◽  
Author(s):  
Zengkui Lu ◽  
Huihua Wang ◽  
Youji Ma ◽  
Mingxing Chu ◽  
Kai Quan ◽  
...  
Keyword(s):  
Heat Stress ◽  
Signaling Pathways ◽  
Stress Responses ◽  
Large Scale ◽  
Ovis Aries ◽  
Stop Codons ◽  
Coding Regions ◽  
Mrna Methylation ◽  
Response To Stress ◽  
And Control

Abstract Background: Intensive and large-scale development of the sheep industry and increases in global temperature are increasingly exposing sheep to heat stress. N6-methyladenosine (m6A) mRNA methylation varies in response to stress, and can link external stress with complex transcriptional and post-transcriptional processes. However, no m6A mRNA methylation map has been obtained for sheep, nor is it known what effect this has on regulating heat stress in sheep. Results: A total of 8,306 and 12,958 m6A peaks were detected in heat stress and control groups, respectively, with 2,697 and 5,494 genes associated with each. Peaks were mainly enriched in coding regions and near stop codons with classical RRACH motifs. Methylation levels of heat stress and control sheep were higher near stop codons, although methylation was significantly lower in heat stress sheep. GO revealed that differential m6A-containing genes were mainly enriched in the nucleus and were involved in several stress responses and substance metabolism processes. KEGG pathway analysis found that differential m6A-containing genes were significantly enriched in Rap1, FoxO, MAPK, and other signaling pathways of the stress response, and TGF-beta, AMPK, Wnt, and other signaling pathways involved in fat metabolism. These m6A-modified genes were moderately expressed in both heat stress and control sheep, and the enrichment of m6A modification was significantly negatively correlated with gene expression. Conclusions: Our results showed that m6A mRNA methylation modifications regulate heat stress in sheep, and it also provided a new way for the study of animal response to heat stress.

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