Long & Medium Term Research: Cyclin Destruction in Meiotic and Early Mitotic Cell Cycles of Xenopus Laevis

长期和中期研究：非洲爪哇减数分裂和早期有丝分裂细胞周期中细胞周期蛋白的破坏这个奖项的推荐是根据外国卓越中心的长期和中期研究计划提出的。该计划旨在使美国科学家和工程师能够在国外被证明是优秀的研究机构进行长期研究。奖项提供了开展联合研究的机会，并利用外国独特或配套的设施、专门知识和实验条件。该奖项由Jolinda A.Traugh博士发起，将支持伊丽莎白·曼德利博士为期12个月的博士后研究访问英国，与伦敦城市大学生理系的迈克尔·惠特克博士合作，关于“在海胆的减数分裂和早期有丝分裂细胞周期中周期蛋白的破坏。”研究人员建议在早期海胆发育的快速细胞周期的M期研究细胞周期蛋白破坏的机制。细胞周期蛋白只在M期是不稳定的，初步证据表明在这一过程中存在蛋白磷酸化和去磷酸化的调节级联反应。一些证据表明，钙可能参与了破坏过程。在由非洲爪蛙卵制备的无细胞系统中，通过添加活性的细胞周期蛋白/p34-cdc2复合体，可以触发细胞周期蛋白的破坏。销毁需要三磷酸腺苷以及可溶物质和颗粒物质的参与。这表明可能与高分子量的多功能蛋白水解酶有关，从而与泛素有关。研究人员将通过寻找泛素化的周期蛋白中间体和分级来调查环素降解是否涉及泛素。他们还将调查钙在破坏过程中所起的作用。更广泛地说，他们将试图净化和尽可能确定销毁系统的部件。奖励建议提供资金，酌情支付国际旅行、当地出国旅行、津贴、受抚养人津贴(如果适用)，以及为美国本土机构提供250美元的固定行政津贴。

Long & Medium-Term Research: Cyclin Destruction in Meiotic and Early Mitotic Cell Cycles of Xenopus Laevis This award recommendation is made under the Program for Long & Medium-Term Research at Foreign Centers of Excellence. The program seeks to enable U.S. scientists and engineers to conduct long-term research abroad at research institutions of proven excellence. Awards provide opportunities for the conduct of joint research, and the use of unique or compli- mentary facilities, expertise and experimental conditions in foreign countries. This award for a proposal sponsored by Dr. Jolinda A. Traugh, will support a 12-month postdoctoral research visit by Dr. Elizabeth Mandley to the United Kingdom to work with Dr. Michael Whitaker of the Department of Physiology of the University of the City of London, on "Cyclin Destruction in Meiotic and Early Mitotic Cell Cycles of Sea Urchins (Xenopus)." The investigators propose to investigate the mechanism of cyclin destruction during the M-phase of the rapid cell cycles of early sea urchin development. Cyclin is only unstable during M-phase, and preliminary evidence implicates a regulatory cascade of protein phosphorylation and desphosphorylation in the process. Some evidence suggests calcium may be involved in the destruction process. Cyclin destruction can be triggered in a cell-free system prepared from Xenopus eggs by addition of active cyclin/p34-cdc2 complex. Destruction requires ATP and the participation of both soluble and particulate material. This suggests that the high molecular weight multifunctional protease and hence ubiquitin may be involved. The investigators will investigate whether cylcin degradation involves ubiquitin by searching for ubiquitinated intermediates of cyclin, and by fractiona- tion. They will also investigate the role that calcium plays in the destruction process. More generally, they will attempt to purify and identify as far as possible the components of the destruction system. The award recommendation provides funds to cover, as appropriate, international travel, local travel abroad, stipend, dependents' allowance if applicable, and a flat administrative allowance of $250 for the U.S. home institution.