植物细胞程序性死亡的分类和膜通透性调控蛋白研究进展

程序性细胞死亡是由基因调控的贯穿于真核细胞生理和发育过程的细胞自杀行为。动物细胞的程序性死亡分成3类凋亡、自噬和坏死；线粒体和溶酶体分别在前两个过程中起关键作用。关于植物细胞程序性死亡的分类还存在很多争议，焦点是植物是否有细胞凋亡这种形式，核心问题是植物细胞的线粒体外膜上没有Bcl-2家族的膜通透性调控蛋白。近年，程序性细胞死亡也在细菌中发现，LrgAB家族的膜通透性调控蛋白起着重要作用。最近的研究表明，植物叶绿体外被膜上也有LrgAB家族的同源蛋白，它们在控制叶绿体发育和程序性细胞死亡方面起重要作用。因此，叶绿体在植物细胞死亡调控中的作用应该更加受到关注。

Progress in the Classification of Plant Programmed Cell Death and the Regula- tory Protein for Membrane Permeabilization

Programmed cell death （PCD） is a genetically controlled process of cell suicide, which can be induced in physiology and development of eukaryotic cells. Currently, three types of PCD have been noticed in animal cells： apoptosis, autophagy and necrosis. Mitochondria and lysosomes play a vital role in apoptosis and autophagy, respectively. However, there exists controversy on the categories of plant PCD, focusing on whether apoptosis occurs in plant cells, due to the apparent absence of the Bcl-2 family proteins, the key regulators of membrane permeability in outer membrane of mitochondria. Recently, PCD was identified in bacteria, and the LrgAB family proteins was found to play a cental role in the regulation of membrane permeability. In the envelope membrane of chloroplasts, homologues of LrgAB family proteins have been identified, and their role in chloroplast development and plant PCD control have been revealed. Thus, we should pay more attention on chloroplast which may have a prominent role in plant PCD control.