Schultz T F, Quatrano R S
Department of Biology, University of North Carolina, Chapel Hill 27599-3280, USA.
Plant Mol Biol. 1997 Jun;34(3):557-62. doi: 10.1023/a:1005870227632.
In order to identify proteins that interact with plant transcriptional complexes, we performed a two-hybrid screen in yeast using a cDNA library from embryogenic rice suspension cultures and the plant transcriptional activator viviparous-1 (vp1) as 'bait'. In this screen, we detected an interaction between VP1 and a rice homologue of the Saccharomyces cerevisiae RAD23 gene (osRAD23). The RAD23 protein is associated with the general transcriptional machinery in yeast, and is believed to play a role in the processes of nucleotide excision repair in yeast and mammalian cells. This report is the first identification of a RAD23 homolog in plants. The osRAD23 amino acid sequence shares 50-60% similarity throughout its length with RAD23 sequences from yeast, mice, and man. osRAD23 contains a characteristic ubiquitin-like domain at its N-terminus, which is similar to other RAD23 genes. Analysis of the expressed sequence tag database identifies two different classes of RAD23 genes in both Arabidopsis and rice. Southern analysis of rice genomic DNA indicated the presence of at least two RAD23-like genes. A single transcript (1.5 kb) of osRAD23 was detected in total RNA from rice embryonic tissue, while three transcripts (1.8, 1.5 and 1.0 kb) were observed in total RNA from vegetative tissues of rice.
为了鉴定与植物转录复合体相互作用的蛋白质，我们以水稻胚性悬浮培养物的cDNA文库和植物转录激活因子胎萌-1（vp1）作为“诱饵”，在酵母中进行了双杂交筛选。在该筛选中，我们检测到VP1与酿酒酵母RAD23基因的水稻同源物（osRAD23）之间存在相互作用。RAD23蛋白与酵母中的一般转录机制相关，并且被认为在酵母和哺乳动物细胞的核苷酸切除修复过程中发挥作用。本报告首次在植物中鉴定出RAD23同源物。osRAD23氨基酸序列在其全长范围内与酵母、小鼠和人类的RAD23序列具有50-60%的相似性。osRAD23在其N端含有一个特征性的泛素样结构域，这与其他RAD23基因相似。对表达序列标签数据库的分析在拟南芥和水稻中鉴定出两种不同类型的RAD23基因。水稻基因组DNA的Southern分析表明至少存在两个RAD23样基因。在水稻胚胎组织的总RNA中检测到osRAD23的单一转录本（1.5 kb），而在水稻营养组织的总RNA中观察到三种转录本（1.8、1.5和1.0 kb）。
