Dynein independent roles for dynein light chain in meiotic progression

动力蛋白轻链在减数分裂过程中的独立作用

• 批准号: 9467226
• 负责人: Sara Fielder
• 金额: $ 4.45万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9467226
• 关键词: Adult; Affect; Aneuploidy; Apoptosis; Binding; Binding Proteins; Binding Sites; CRISPR/Cas technology; Caenorhabditis elegans; Chromatin; Chromosome Pairing; Chromosomes; Chromosomes, Human, Pair 3; Coiled-Coil Domain; Consensus; Coupled; Defect; Development; Dimerization; Disease; Dissection; Dynein ATPase; Embryo; Female; Genetic; Germ Cells; Goals; Hermaphroditism; Homologous Gene; Human; Immunofluorescence Immunologic; Impairment; Incidence; Infertility; Interruption; Lead; Light; Mass Spectrum Analysis; Meiosis; Methods; Motor; Movement; N-terminal; Nuclear Envelope; Oogenesis; Organism; Orthologous Gene; Parents; Phenotype; Polyploidy; Process; Proteins; RNA Interference; Regulation; Reporting; Resources; Role; Sex Characteristics; Sex Chromosomes; Spermatogenesis; Stains; Stress; Synapses; Synaptonemal Complex; System; Temperature; Testing; Therapeutic Intervention; Time; Western Blotting; Work; Zinc Fingers; base; dimer; dynactin; dynein light chain; egg; genetic information; insight; knock-down; male; mutant; offspring; prevent; protein structure; sex; sperm cell

Project Summary Homologous chromosome pairing and meiotic synapsis are essential processes that are required in both oogenesis and spermatogenesis to prevent aneuploidy and developmental defects in offspring. Despite the importance and high conservation of synapsis, not every aspect is the same between the two sexes. Heterogametic species have evolved less stringent or differential regulation of meiotic pairing and synapsis in order to successfully pass on their genetic information. My preliminary results indicate that male and female C. elegans even have different requirements for dynein in regulating the initiation of synapsis. Dynein dependent forces have been proposed to test that a potential homolog match is correct, and once this has been established, synapsis (SYP) protein loading between the homologs initiates. Knockdown of the dynein light chain (DLC-1) at an elevated temperature results in SYP polycomplex formation away from chromatin in females. Unexpectedly, DLC-1 depletion in males at the same temperature shows grossly normal synapsis. Even more surprisingly, mutants in the heavy chain and dynactin components of dynein also do not show SYP polycomplexes in female meiosis. This indicates that there is a previously undescribed function for DLC-1 in synapsis initiation. There are many examples of dynein-independent functions for DLC-1, including stabilizing or interrupting dimer interactions. A consensus binding motif for the DLC-1 ortholog has been reported, and there is a potential binding motif in one of the SYP proteins. I hypothesize that DLC-1 functions to regulate SYP protein interactions until correct pairing has been verified. I further hypothesize that males employ an alternative method to regulate synapsis initiation. Specific Aim I investigates the role that DLC-1 has in female meiosis by testing if it interacts directly with synapsis proteins, and DLC-1 interactors in female meiosis will be identified and tested for a role in synapsis initiation. Specific Aim II focuses on why males do not require DLC-1 by assessing if males need dynein at all in pairing chromosomes, and investigate whether a redundancy in light chains evolved in male meiosis. Understanding such sex specific differences in meiotic regulation using a genetically tractable organism will help us better understand natural and disease states in humans that lead to an increased incidence of aneuploidy and meiotically based infertility.

项目摘要 同源染色体配对和减数分裂联会是这两个过程所必需的基本过程 卵子发生和精子发生，以防止后代的非整倍性和发育缺陷。尽管 虽然突触的重要性和高度保守性，但两性之间并不是每个方面都是一样的。 异配子体物种在减数分裂配对和联会中进化出不那么严格或差异的调节， 才能成功传递他们的基因信息。我的初步结果表明，男性和女性C。 秀丽线虫在调节突触起始时对动力蛋白的需求也不同。动力蛋白依赖性 已经提出了一些力量来测试潜在的同源匹配是正确的，一旦这已经被证明是正确的。 同源物之间的突触（SYP）蛋白加载启动。动力蛋白光的敲除 链（DLC-1）在升高的温度下导致SYP多复合物形成远离染色质， 女性出乎意料的是，在相同温度下雄性的DLC-1消耗显示出非常正常的突触。 更令人惊讶的是，动力蛋白的重链和动力蛋白组分中的突变体也不显示SYP。 在女性减数分裂的复合体。这表明，DLC-1具有以前未描述的功能， 突触起始DLC-1有许多与动力蛋白无关的功能，包括稳定 或中断二聚体相互作用。已经报道了DLC-1直系同源物的共有结合基序， 在其中一种SYP蛋白中存在潜在的结合基序。我假设DLC-1的功能是调节 SYP蛋白相互作用，直到正确配对已被验证。我进一步假设，男性雇用一个 另一种调节突触起始的方法。具体目标I研究DLC-1在女性中的作用 通过测试它是否直接与突触蛋白相互作用，女性减数分裂中的DLC-1相互作用物将被 被鉴定和测试在突触起始中的作用。具体目标II重点介绍为什么男性不需要DLC-1 通过评估男性在配对染色体时是否需要动力蛋白，并调查是否存在冗余， 轻链在雄性减数分裂中进化。使用一种新的方法来理解减数分裂调控中的性别特异性差异， 遗传上易处理的生物体将帮助我们更好地了解人类的自然和疾病状态， 非整倍体和减数分裂不育的发生率增加。