Molecular system ensuring genomic inheritance through successive generations

确保基因组遗传代代相传的分子系统

基本信息

批准号：
14208088
负责人：
KISHIMOTO Takeo
金额：
$ 34.2万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14208088/
关键词：
cell cycle control nuclear formation meiosis fertilization DNA replication signal transduction cyclin-CDK Mos-MAPK 前核形成 PI3キナーゼインポーチンα Mcm p90Rsk 染色体構築ヒトデ卵カエル卵

项目摘要

Molecular mechanisms that ensure genomic inheritance through successive generations have been studied, based on the cell cycle control and the nuclear formation. Our findings are summarized below.1. Meiotic cell cycle progression : Almost complete signaling pathway that leads to meiotic reinitiation in starfish oocytes has been revealed to be composed of the putative receptor for maturation-inducing hormone, 1-MeAde / Gβ1γ2 / I-β type PI3-kinase / PDK1 and putative PDK2 / Akt (PKB) / Cdc2-cyclin B / Plk1. After meiotic reinitiation, p90Rsk is activated immediately downstream of the Mos-MAPK pathway to regulate positively both meiosis I to II transition and G1-phase arrest after completion of meiosis II.2. Formation of male and female pronuclei : Cell-free extracts derived from Xenopus oocytes or eggs were utilized to analyze these processes. Upon fertiliztion, NAP1 functions as a molecular chaperone for histone H1 at the chromatin remodeling in sperm nuclei. During oocyte maturation, the ability of nuclear import that depends on importin α is accelerated, and the LI-type nuclear lamin is newly synthesized, possibly providing a clue to understand how the ability for nuclear formation is acquired in this period.3. Initiation of S-phase upon fertilization : In unfertilized mature eggs of starfish, MCMs are already loaded onto chromatin in female pronucleus, but the loading of Cdc45, which allows the loading of DNA polymerase a to DNA, is prevented downstream of the Mos-MAPK-p90Rsk pathway. Abolishment of p90Rsk activity is sufficient for initiation of DNA replication, thus providing a clue to answer the classic question in biology how fertilization initiates S-phase.

根据细胞周期控制和核形成，已经研究了通过成功世代进行基因组遗传的分子机制。我们的发现在下面总结了1。减数分裂细胞周期的进展：已经揭示了导致海星卵母细胞减数分裂的几乎完整的信号传导途径，已揭示由推定的受体组成，用于成熟诱导马酮，1-meade /gβ1γ2 / I-i-i-β型PI3-β型PI3-基因酶 / pdk1 / pdk1和PDK2 / PLINATIVE PDK2 / PLEC / PLIN BBB1 / cdc1 / cdc2-cc1 / cdc2-cc。减数分裂重新定性后，p90rsk立即在MOS-MAPK途径的下游激活，以正向减数分裂I到II转变和G1相滞留，并在减数分裂II.2完成后均受到p90RSK的积极调节。雄性和雌性原核的形成：源自爪蟾卵母细胞或卵的无细胞提取物来分析这些过程。受精后，NAP1充当了精子核中染色质重塑的组蛋白H1的分子链酮。在卵母细胞成熟期间，依赖于进口蛋白α的核进口能力得到加速，而Li-Type核层粘连蛋白是新合成的，这可能提供了一个线索，以了解如何在此期间获得核形成的能力。3。施肥后S期的开始：在未施用的海星成熟卵中，MCMS已经在雌性前核中加载到染色质上，但是Cdc45的负载可以使DNA聚合酶A至DNA的加载，以防止MOS-MAPK-P90RSK PATHWOWAY的下游DNA至DNA。废除P90RSK活性足以启动DNA复制，从而提供了一个线索来回答生物学中的经典问题，从而施肥如何启动S期。