Pérez-Pérez José M, Serralbo Olivier, Vanstraelen Marleen, González Cristina, Criqui Marie-Claire, Genschik Pascal, Kondorosi Eva, Scheres Ben
Department of Molecular Genetics, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
Plant J. 2008 Jan;53(1):78-89. doi: 10.1111/j.1365-313X.2007.03312.x. Epub 2007 Oct 17.
To investigate the specialization of the two Arabidopsis CDC27 subunits in the anaphase-promoting complex (APC/C), we analyzed novel alleles of HBT/CDC27B and CDC27A, and characterized the expression of complementing HOBBIT (HBT) protein fusions in plant meristems and during the cell cycle. In contrast to other APC/C mutants, which are gametophytic lethal, phenotypes of weak and null hbt alleles indicate a primary role in the control of post-embryonic cell division and cell elongation, whereas cdc27a nulls are phenotypically indistinguishable from the wild type. However, cdc27a hbt double-mutant gametes are non-viable, indicating a redundant requirement for both CDC27 subunits during gametogenesis. Yeast-two-hybrid and pulldown studies with APC/C components suggest that the two Arabidopsis CDC27 subunits participate in several complexes that are differentially required during plant development. Loss-of-function analysis, as well as cyclin B reporter protein accumulation, indicates a conserved role for the plant APC/C in controlling mitotic progression and cell differentiation during the entire life cycle.
为了研究拟南芥中两个细胞分裂周期蛋白27（CDC27）亚基在后期促进复合体（APC/C）中的特异性，我们分析了HBT/CDC27B和CDC27A的新等位基因，并对互补的霍比特蛋白（HBT）融合蛋白在植物分生组织和细胞周期中的表达进行了表征。与其他配子体致死的APC/C突变体不同，弱等位基因和无效hbt等位基因的表型表明其在控制胚后细胞分裂和细胞伸长中起主要作用，而cdc27a无效突变体在表型上与野生型无差异。然而，cdc27a hbt双突变配子是无活力的，这表明在配子发生过程中两个CDC27亚基都有冗余需求。酵母双杂交和与APC/C组分的下拉实验表明，拟南芥的两个CDC27亚基参与了植物发育过程中不同需求的几个复合体。功能丧失分析以及细胞周期蛋白B报告蛋白的积累表明，植物APC/C在整个生命周期中控制有丝分裂进程和细胞分化方面具有保守作用。
