Investigations Into Mitotic Motility

该项目将研究移动染色体的有丝分裂运动系统的性质。其具体目的是区分和描述共同产生二倍体运动性的不同成分，并确定哪些成分参与染色体运动。我们将在最高的显微分辨率下检查AXE的运输特性，然后将代谢抑制剂对极向和反极向运动的影响与前中期染色体的行为进行比较。首席研究人员将确定高等植物纺锤体是否表现出类似于代谢抑制剂诱导的放射状组织的中心哺乳动物纺锤体中前中期染色体收缩的反应，该纺锤体具有宽阔的开放极点。对膜质的类似观察可能表明它的运输性质与星体运输有什么共同之处。渗透性细胞模型成功地研究了后期A，现在将被用于尝试重新激活前中期染色体活动和星体运输。研究将通过将PTK细胞暴露于ATP和各种类似物和抑制剂来检查染色体运动和任何同时发生的微管分解。负责细胞分裂过程中染色体运动的机制仍然是细胞生物学中最不了解但却很重要的问题之一。在本项目过程中取得的关于极地和反极运输的比较生理学的结果，应大大有助于我们对这些机制的理解。

The project will investigate the nature of the mitotic motility systems that move chromosomes. The specific aim is to distinguish between and characterize the different components that collectively generate motility in the aster, and to determine which are involved in chromosome movement. The transport properties of the aster will be examined at highest microscopic resolution, and then the effects of metabolic inhibitors on the polewards and antipolewards movements will be compared with the behaviour of prometaphase chromosomes. The principal investigator will ascertain whether the higher plant spindle, with its broad open poles, shows a response similar to the contraction of prometaphase chromosomes induced in the radially organized, centric mammalian spindle by metabolic inhibitors. Similar observations on the phragmoplast may show what its transport properties have in common with astral transport. The permeabilized cell model, successful in investigating anaphase A, will now be used in attempts to reactivate prometaphase chromosome activity and astral transport. Studies will examine chromosome movement, and any concurrent microtubule disassembly,by exposing PtK cells to ATP and various analogs and inhibitors. The mechanisms responsible for chromosome movement during cell division remain one of the least understood, but important issues in cell biology. Results obtained during the course of this project, on the comparative physiology of polar and antipolar transport, should substantially contribute to our understanding of these mechanisms.