Sturm A, Lienhard S
Friedrich Miescher Institute, Basel, Switzerland.
Plant J. 1998 Mar;13(6):815-21. doi: 10.1046/j.1365-313x.1998.00075.x.
DNA repair by nucleotide excision (NER) has been demonstrated in plant cells at the biochemical level but until now none of the molecular components of the plant NER complex has been identified. In this paper, the cloning and characterization of two isoforms of RAD23 from carrot (Daucus carota L.) are reported. It has been suggested that RAD23 in yeast is an assembly factor of the NER complex required for transcription-coupled repair as well as efficient overall genome repair. A functional assay demonstrated that both plant homologues complement the UV-sensitive phenotype of a rad23 deletion mutant of yeast. This result suggests that homologous polypeptides may catalyse NER in plants and yeast and, possibly, by a similar mechanism.
核苷酸切除修复（NER）在植物细胞中已在生化水平得到证实，但到目前为止，植物NER复合物的分子成分尚未被鉴定出来。本文报道了胡萝卜（Daucus carota L.）中RAD23两种同工型的克隆与鉴定。有研究表明，酵母中的RAD23是转录偶联修复以及高效全基因组修复所需的NER复合物的组装因子。功能分析表明，这两种植物同源物都能弥补酵母rad23缺失突变体的紫外线敏感表型。这一结果表明，同源多肽可能在植物和酵母中催化NER，并且可能通过类似的机制。
