Bar-Sagi D
Cold Spring Harbor Laboratory, New York 11724.
Anticancer Res. 1989 Sep-Oct;9(5):1427-37.
Ras genes are an ubiquitous eukaryotic gene family. Since their discovery as the cellular homologues of the transforming genes of Harvey and Kirsten retroviruses, ras genes have been presumed to play a role in growth control, mainly because of their potential to induce uncontrolled cell proliferation. This notion is strongly supported by recent evidence indicating that ras mutations may be causative or closely linked to the onset of some types of human tumors. However, the mechanism of action of ras proteins in mammalian cells is poorly understood. Using the microinjection technique as a biological assay for ras proteins, it has been possible to address several important questions concerning cellular and biochemical aspects of ras function. When introduced into living cells by microinjection, purified ras proteins can induce cell proliferation, neuronal differentiation, oocyte maturation, and exocytotic degranulation. On the biochemical level, microinjection studies indicated that ras proteins can induce specific alterations in phospholipid metabolism.
Ras基因是一种普遍存在的真核基因家族。自从它们作为哈维氏和克里斯蒂安氏逆转录病毒转化基因的细胞同源物被发现以来，ras基因一直被认为在生长控制中起作用，主要是因为它们具有诱导细胞不受控制增殖的潜力。最近的证据有力地支持了这一观点，这些证据表明ras突变可能是某些类型人类肿瘤发病的原因或与之密切相关。然而，ras蛋白在哺乳动物细胞中的作用机制仍知之甚少。利用显微注射技术作为ras蛋白的生物学检测方法，已经能够解决几个关于ras功能的细胞和生化方面的重要问题。当通过显微注射将纯化的ras蛋白引入活细胞时，它可以诱导细胞增殖、神经元分化、卵母细胞成熟和胞吐脱颗粒。在生化水平上，显微注射研究表明ras蛋白可以诱导磷脂代谢的特定改变。
