Larkins B A, Dilkes B P, Dante R A, Coelho C M, Woo Y M, Liu Y
Department of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA.
J Exp Bot. 2001 Feb;52(355):183-92.
Endoreduplication is a form of nuclear polyploidization that results in multiple, uniform copies of chromosomes. This process is common in plants and animals, especially in tissues with high metabolic activity, and it generally occurs in cells that are terminally differentiated. In plants, endoreduplication is well documented in the endosperm and cotyledons of developing seeds, but it also occurs in many tissues throughout the plant. It is thought that endoreduplication provides a mechanism to increase the level of gene expression, but the function of this process has not been thoroughly investigated. Numerous observations have been made of endoreduplication, or at least extra cycles of S-phase, as a consequence of mutations in genes controlling several aspects of cell cycle regulation. However, until recently there were few studies directed at the molecular mechanisms responsible for this specialized cell cycle. It is suggested that endoreduplication requires nothing more elaborate than a loss of M-phase cyclin-dependent kinase activity and oscillations in the activity of S-phase cyclin-dependent kinase.
核内复制是核多倍体化的一种形式，它会产生多个均匀的染色体拷贝。这个过程在植物和动物中很常见，尤其是在代谢活性高的组织中，并且通常发生在终末分化的细胞中。在植物中，核内复制在发育种子的胚乳和子叶中有充分的记录，但它也发生在植物的许多组织中。人们认为核内复制提供了一种增加基因表达水平的机制，但这个过程的功能尚未得到充分研究。由于控制细胞周期调控多个方面的基因突变，已经观察到许多核内复制现象，或者至少是S期的额外循环。然而，直到最近，针对这种特殊细胞周期的分子机制的研究还很少。有人提出，核内复制只需要M期细胞周期蛋白依赖性激酶活性的丧失和S期细胞周期蛋白依赖性激酶活性的振荡。
