Choi D W, Song J Y, Kwon Y M, Kim S G
Department of Biology, Seoul National University, Seoul, Korea.
Plant Mol Biol. 1996 Mar;30(5):973-82. doi: 10.1007/BF00020808.
A cDNA clone, corresponding to mRNAs preferentially expressed in the roots of bean (Phaseolus vulgaris L.) seedlings, was isolated. This clone contains a 381 bp open reading frame encoding a polypeptide of 13.5 kDa, designated PVR5 (Phaseolus vulgaris root 5). The amino acid sequence of this clone is rich in proline (13.5%) and leucine (12.7%) and shares significant amino acid sequence homology with root-specific and proline-rich proteins from monocots (maize and rice), and proline-rich proteins from dicots (carrot, oilseed rape, and Madagascar periwinkle). The precise biological roles of these polypeptides are unknown. PVR5 mRNA accumulation is developmentally regulated within the root, with high levels at the root apex and declining levels at distances further from the root tip. In situ hybridization shows that PVR5 mRNA specifically accumulates in the cortical ground meristem in which maximal cell division occurs. Southern blot analysis suggests that genomic DNA corresponding to PVR5 cDNA is encoded by a single gene or a small gene family.
分离出了一个与在菜豆（Phaseolus vulgaris L.）幼苗根中优先表达的mRNA相对应的cDNA克隆。该克隆包含一个381 bp的开放阅读框，编码一个13.5 kDa的多肽，命名为PVR5（菜豆根5）。该克隆的氨基酸序列富含脯氨酸（13.5%）和亮氨酸（12.7%），并与单子叶植物（玉米和水稻）的根特异性和富含脯氨酸的蛋白质以及双子叶植物（胡萝卜、油菜和长春花）的富含脯氨酸的蛋白质具有显著的氨基酸序列同源性。这些多肽的确切生物学作用尚不清楚。PVR5 mRNA在根内的积累受发育调控，在根尖处水平较高，而在离根尖较远的部位水平下降。原位杂交显示，PVR5 mRNA特异性地积累在发生最大细胞分裂的皮层基本分生组织中。Southern印迹分析表明，与PVR5 cDNA相对应的基因组DNA由一个单基因或一个小基因家族编码。
