NIMA-like Kinase NEK1 as a Regulator of Mammalian Gametogenesis

项目总结 减数分裂是一种特殊的细胞分裂，其特征是先进行一轮dna复制，然后再进行两轮。 染色体分离，导致配子的形成。粘附素是一种与染色体相关的 多蛋白环，维持姐妹染色单体的凝聚力，这是准确的 染色体/染色单体分离。在减数分裂过程中，粘附素的分解尤其复杂，因为 在第一次减数分裂(MI)时沿染色体臂顺序失去凝聚力的要求 然后在第二次减数分裂期间的着丝粒(MII)。NIMA-like kinase1(NEK1)是一种双重特异的 丝氨酸/苏氨酸和酪氨酸激酶，在生殖细胞中高度表达。小鼠中NEK1的缺失导致 心肌梗塞和随后的不孕症时染色体臂上粘附素亚单位SMC3的保留。粘附素去除 被编排成两个步骤，第一步是“前期途径”，第二步是分离酶介导的切割 粘附环。前期途径由类翼状蛋白之间的化学计量比确定 (WAPL)和Sororin，它们竞争与粘附素环上的Pds5B结合，但这一途径尚未 在减数分裂中被描述过。我的初步数据显示，NEK1在调节凝集素方面发挥了令人兴奋的作用 心肌梗塞的动力学，既直接在粘附素亚单位SMC3、RAD21L和Rec8水平上，也间接在粘附素亚基水平上 通过磷酸化Pds5B-WAPL复合体。此外，我的研究表明，NEK1的作用 在前期途径上是通过蛋白磷酸酶1-γ(pp1γ)介导的，而pp1-Gamma是 NEK1，它结合和去磷酸化WAPL。此外，我的初步研究表明，NEK1 还调节一系列其他NEK蛋白，使其在心肌梗死中发挥不同于其在 凝聚力动态。因此，我假设NEK1在减数分裂过程中扮演着主要调节者的角色，主要 通过对心肌梗塞的关键组件的作用，在心肌梗塞时粘附素的去除时间上发挥关键作用 前期途径，但也在协调其他NEK激酶的行动。我的长期目标是澄清 NEK1如何调节心肌梗塞时的凝聚力去除，但也进一步表征了NEK1催化活性的作用 在两个减数分裂阶段协调下游活动。提出了三个具体目标：(1) 阐明NEK1在PP1WAPLγ磷酸化中的作用，(2)评估WAPL的重要性 心肌梗死时凝聚力去除的磷酸化以及(3)阐明NEK1作为一种主要调节因子的功能。 在减数分裂过程中的NEK家族。这些实验将提供新的和令人兴奋的数据来描述，为 首次研究了NEK1在减数分裂前期途径中调节粘附素去除中的作用。 申请人Brieño-Enríquez博士是医学博士，在配子生物学领域拥有相当丰富的经验。 申请者研究了人类和小鼠不同的配子生物学过程，目的是了解 产生健康配子以进行有性繁殖的复杂事件。的最终目标是 申请者将建立一个独特的和最先进的研究计划，旨在了解如何 哺乳动物的减数分裂和配子发生是受调控的，在人类中什么事件可能是有缺陷的，其中 与减数分裂相关的错误率非常高。因此，已经制定了职业发展计划。 成立的目的是为Brieño-Enríquez博士提供所有必要的工具，以建立强有力的研究计划 在一所一流的学术机构。除了现有的最好的科学资源，布里尼奥-恩里克斯博士还将 受益于他的主办机构康奈尔大学提供的各种研讨会和研讨会。 主题包括找工作，准备申请和面试，洽谈创业 打包，建立实验室，建设一支有效的研究团队。此外，还有一些课程专门针对 提高教学技能，写助学金，以及处理工作场所的冲突，仅举几例。Dr。 布里尼奥-恩里克斯还将受益于一个由他的导师保拉·科恩博士领导的杰出的指导团队 和马克·罗伯逊博士，都在生殖生物学领域享有很高的声誉，而且都有很多 指导成功的博士后研究员的经验。支持这个指导团队是一个杰出的 咨询委员会由激酶生物学领域的专家(马库斯·斯莫尔卡博士)、粘附素(Dr。 迈克尔·戈德堡)，老鼠的转基因和繁殖(约翰·希门蒂博士)。申请者将会见 经常与他的导师和顾问团队在一起，无论是非正式的还是正式的。此外，导师和 咨询委员会承诺帮助布里尼奥-恩里克斯博士发展他的研究技能，以及 将帮助他制定一份强有力的教职申请、工作研讨会和粉笔演讲。最后，科恩博士承诺 通过Brieño-Enríquez博士的研究为他提供财政支持，并为他提供持续的指导 过渡到他新独立的职位。 总而言之，布里尼奥-恩里克斯博士设计了一项令人兴奋的新奇提议，试图定义 减数分裂细胞分裂中的尼玛样蛋白。在这样做的过程中，他将为 他自己在配子生物学领域。为了帮助他，他组建了一支世界级的指导团队和一个 强有力的发展计划，一切都有一个统一的目标，推动这一向独立的成功过渡 激动人心的年轻科学家

Project summary Meiosis is a specialized cell division characterized by a single round of DNA replication followed by two rounds of chromosome segregation, resulting in the formation of gametes. Cohesin is a chromosome-associated multiprotein ring that maintains sister chromatid cohesion, and which is essential for accurate chromosome/chromatid segregation. During meiosis, cohesin disassembly is particularly complicated by the requirement for sequential loss of cohesion along the chromosome arms at the first meiotic division (MI) and then at the centromere during the second meiotic division (MII). NIMA-like kinase 1 (NEK1) is a dual specific serine/threonine and tyrosine kinase that is highly expressed in germ cells. Loss of NEK1 in mice leads to retention of the cohesin subunit SMC3 on chromosome arms at MI and subsequent infertility. Cohesin removal is orchestrated in two steps, first by “the prophase pathway”, followed by Separase-mediated cleavage of the cohesin ring. The prophase pathway is defined by the stoichiometry between the Wings-apart-like protein (WAPL) and Sororin, which compete for binding to PDS5B on the cohesin ring, but this pathway has not yet been described in meiosis. My preliminary data reveal exciting roles for NEK1 in the regulation of cohesin dynamics at MI, both directly at the level of the cohesin subunits, SMC3, RAD21L and REC8, and indirectly through phosphorylation the PDS5B-WAPL complex. Furthermore, my studies have shown that NEK1 action on the prophase pathway is mediated via Protein Phosphatase 1-gamma (PP1γ), which is a phosphotarget of NEK1, and which binds and de-phoshphorylates WAPL. Moreover, my preliminary studies indicate that NEK1 also regulates a cascade of other NEK proteins to perform other roles in MI that are distinct from its activity on cohesion dynamics. Thus, I hypothesize that NEK1 acts as master regulator of events in meiosis, primarily playing a crucial role in the timing of cohesin removal at MI through its actions on critical components of the prophase pathway, but also in orchestrating the actions of other NEK kinases. My long term goal is to elucidate how NEK1 regulates cohesion removal at MI, but also to further characterize the role of NEK1 catalytic activity in orchestrating downstream events at both meiotic divisions. Three specific aims are proposed: (1) To elucidate the role of NEK1 in the phosphorylation of PP1γ, (2) To assess the importance of WAPL phosphorylation on cohesion removal at MI and (3) To elucidate the function of NEK1 as a master regulator of the NEK family during meiosis. These experiments will provide a novel and exciting data that describes, for the first time, the the role of NEK1 in the regulation of cohesin removal during the prophase pathway in meiosis. The applicant, Dr. Brieño-Enríquez, is an MD, PhD with considerable experience in the field of gamete biology. The applicant has studied distinct process of gamete biology in humans and mice, with a goal to understanding the complex events that give rise to healthy gametes for sexual reproduction. The ultimate goal of the applicant is to establish a unique and state-of-the-art research program aimed at understanding how mammalian meiosis and gametogenesis is regulated and what events may be defective in humans, where the error rates associated with meiosis are exceptionally high. Thus, a career development plan has been established to provide Dr. Brieño-Enríquez with all the necessary tools to establish a robust research program in a stellar academic institution. In addition to the best scientific resources available, Dr. Brieño-Enríquez will benefit from a wide variety of workshops and seminars available at his host institution, Cornell University. Topics include job searches, preparing an application and preparing for an interview, negotiating a startup package, establishing a lab, and building an effective research team. In addition, there are courses devoted to improving teaching skills, writing grants, and dealing with conflict in the work place, to mention just a few. Dr. Brieño-Enríquez will also benefit from an outstanding mentoring team, led by his mentors, Dr. Paula Cohen and Dr. Mark Roberson, both highly regarded in the field of Reproductive Biology, and both having much experience in mentoring successful postdoctoral fellows. Supporting this mentoring team is an outstanding advisory committee consisting of experts in the field of kinase biology (Dr. Marcus Smolka), cohesins (Dr. Michael Goldberg), mouse transgenesis and reproduction (Dr. John Schimenti). The applicant will meet frequently with his mentors and advisory team, both informally and formally. Moreover, the mentors and advisory committee have committed to assisting Dr. Brieño-Enríquez as he develops his research skills, and will help him to craft a strong faculty application, job seminar, and chalk talk. Lastly, Dr. Cohen has committed to supporting Dr. Brieño-Enríquez financially through his research and to providing ongoing mentorship as he transitions to his newly independent position. In summary, Dr. Brieño-Enríquez has devised an exciting and novel proposal that seeks to define the role of the NIMA-like kinases in the meiotic cell divisions. In doing so, he will create a robust and novel niche for himself in the field of gamete biology. To assist him, he has assembled a world-class mentoring team and a strong development plan, all with a unified goal of promoting the successful transition to independence of this exciting young scientist