Fagarasanu Andrei, Rachubinski Richard A
Department of Cell Biology, University of Alberta, Medical Sciences Building 5-14, Edmonton, Alberta T6G 2H7, Canada.
Curr Opin Microbiol. 2007 Dec;10(6):528-38. doi: 10.1016/j.mib.2007.10.002.
The biochemical functions of eukaryotic cells are often compartmentalized into membrane-bound organelles to increase their overall efficiency. Although some organelles can be formed anew, cells have evolved elaborate mechanisms to ensure the faithful inheritance of their organelles. In contrast to cells that divide by fission, the budding yeast Saccharomyces cerevisiae must actively and vectorially deliver half of its organelles to the growing bud. To achieve this, proteins called formins are strategically localized to the bud, where they assemble an array of actin cables that radiate deep into the mother cell. Class V myosin motors use these cables as tracks to transport various organelles, including peroxisomes, a portion of the vacuole and elements of the endoplasmic reticulum and Golgi complex. By contrast, mitochondria do not engage a myosin motor for their movement but instead use Arp2/3-nucleated actin polymerization for their bud-directed motility. The translocation machineries work cooperatively with molecular devices that retain organelles within both mother cell and bud to ensure an equitable division of organelles between them. While organelle inheritance requires specific proteins tailored for the inheritance of each type of organelle, it is becoming apparent that a set of fundamental rules underlies the inheritance of all organelles.
真核细胞的生化功能通常被区室化到膜结合细胞器中，以提高其整体效率。尽管一些细胞器可以重新形成，但细胞已经进化出复杂的机制来确保细胞器的忠实遗传。与通过裂变分裂的细胞不同，出芽酵母酿酒酵母必须主动且定向地将其一半的细胞器输送到生长中的芽中。为了实现这一点，名为formin的蛋白质被策略性地定位到芽中，在那里它们组装一系列深入母细胞的肌动蛋白电缆。V类肌球蛋白马达利用这些电缆作为轨道来运输各种细胞器，包括过氧化物酶体、一部分液泡以及内质网和高尔基体的成分。相比之下，线粒体的移动不使用肌球蛋白马达，而是利用Arp2/3介导的肌动蛋白聚合来实现其向芽的移动。转运机制与将细胞器保留在母细胞和芽中的分子装置协同工作，以确保细胞器在它们之间公平分配。虽然细胞器遗传需要针对每种细胞器遗传量身定制的特定蛋白质，但越来越明显的是，一组基本规则是所有细胞器遗传的基础。
