Valle G, Bergantino E, Lanfranchi G, Carignani G
Dipartimento di Biologia, Università degli Studi di Padova, Italy.
Yeast. 1991 Dec;7(9):981-8. doi: 10.1002/yea.320070910.
We report the sequence of a 6.3 kb segment of DNA mapping near the end of the right arm of chromosome III of Saccharomyces cerevisiae. The sequence reveals a major open reading frame coding for a putative protein of 1047 amino acids with a striking similarity to the bacterial proteins involved in recognition of mismatched DNA base pairs. This is particularly interesting as the existence of a yeast mismatch repair system similar to that of bacteria has been postulated for some years, but a yeast protein homologous to the bacterial mismatch binding protein had not been identified. The results of a comparison of the putative yeast mismatch binding protein with the bacterial mismatch binding proteins and with two cognate mammalian sequences, support the idea that a similar mismatch repair system may be present also in mammalian cells. The possibility that all of these proteins may have evolved from a common ancestral gene is also discussed.
我们报道了酿酒酵母III号染色体右臂末端附近一段6.3 kb DNA片段的序列。该序列揭示了一个主要的开放阅读框，编码一种推定的含1047个氨基酸的蛋白质，它与参与识别错配DNA碱基对的细菌蛋白质有着显著的相似性。这一点尤其有趣，因为多年来一直推测酵母中存在与细菌类似的错配修复系统，但尚未鉴定出与细菌错配结合蛋白同源的酵母蛋白。将推定的酵母错配结合蛋白与细菌错配结合蛋白以及两个相关的哺乳动物序列进行比较的结果，支持了哺乳动物细胞中也可能存在类似错配修复系统的观点。还讨论了所有这些蛋白质可能都从一个共同祖先基因进化而来的可能性。
