Teotia Sachin, Lamb Rebecca S
Molecular, Cellular, and Developmental Biology Program and Plant Cellular and Molecular Biology Department, Ohio State University, Columbus, Ohio 43210, USA.
Plant Physiol. 2009 Sep;151(1):180-98. doi: 10.1104/pp.109.142786. Epub 2009 Jul 22.
RADICAL-INDUCED CELL DEATH1 (RCD1) and SIMILAR TO RCD ONE1 (SRO1) are the only two proteins encoded in the Arabidopsis (Arabidopsis thaliana) genome containing both a putative poly(ADP-ribose) polymerase catalytic domain and a WWE protein-protein interaction domain, although similar proteins have been found in other eukaryotes. Poly(ADP-ribose) polymerases mediate the attachment of ADP-ribose units from donor NAD(+) molecules to target proteins and have been implicated in a number of processes, including DNA repair, apoptosis, transcription, and chromatin remodeling. We have isolated mutants in both RCD1 and SRO1, rcd1-3 and sro1-1, respectively. rcd1-3 plants display phenotypic defects as reported for previously isolated alleles, most notably reduced stature. In addition, rcd1-3 mutants display a number of additional developmental defects in root architecture and maintenance of reproductive development. While single mutant sro1-1 plants are relatively normal, loss of a single dose of SRO1 in the rcd1-3 background increases the severity of several developmental defects, implying that these genes do share some functions. However, rcd1-3 and sro1-1 mutants behave differently in several developmental events and abiotic stress responses, suggesting that they also have distinct functions. Remarkably, rcd1-3; sro1-1 double mutants display severe defects in embryogenesis and postembryonic development. This study shows that RCD1 and SRO1 are at least partially redundant and that they are essential genes for plant development.
自由基诱导的细胞死亡1（RCD1）和类RCD1蛋白1（SRO1）是拟南芥（Arabidopsis thaliana）基因组中仅有的两个编码蛋白，它们既含有一个假定的聚（ADP - 核糖）聚合酶催化结构域，又含有一个WWE蛋白 - 蛋白相互作用结构域，尽管在其他真核生物中也发现了类似的蛋白。聚（ADP - 核糖）聚合酶介导将来自供体NAD(+)分子的ADP - 核糖单元连接到靶蛋白上，并参与了许多过程，包括DNA修复、细胞凋亡、转录和染色质重塑。我们分别分离出了RCD1和SRO1的突变体rcd1 - 3和sro1 - 1。rcd1 - 3植株表现出如先前分离的等位基因所报道的表型缺陷，最明显的是植株矮小。此外，rcd1 - 3突变体在根系结构和生殖发育维持方面还表现出许多其他发育缺陷。虽然单突变体sro1 - 1植株相对正常，但在rcd1 - 3背景下缺失单剂量的SRO1会增加几种发育缺陷的严重程度，这意味着这些基因确实共享一些功能。然而，rcd1 - 3和sro1 - 1突变体在几个发育事件和非生物胁迫反应中的表现不同，表明它们也具有不同的功能。值得注意的是，rcd1 - 3；sro1 - 1双突变体在胚胎发生和胚后发育中表现出严重缺陷。这项研究表明，RCD1和SRO1至少部分冗余，并且它们是植物发育所必需的基因。
