Jarrous N, Eder P S, Wesolowski D, Altman S
Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520, USA.
RNA. 1999 Feb;5(2):153-7. doi: 10.1017/s135583829800185x.
In HeLa cells, the tRNA processing enzyme ribonuclease P (RNase P) consists of an RNA molecule associated with at least eight protein subunits, hPop1, Rpp14, Rpp20, Rpp25, Rpp29, Rpp30, Rpp38, and Rpp40. Five of these proteins (hPop1p, Rpp20, Rpp30, Rpp38, and Rpp40) have been partially characterized. Here we report on the cDNA cloning and immunobiochemical analysis of Rpp14 and Rpp29. Polyclonal rabbit antibodies raised against recombinant Rpp14 and Rpp29 recognize their corresponding antigens in HeLa cells and precipitate catalytically active RNase P. Rpp29 shows 23% identity with Pop4p, a subunit of yeast nuclear RNase P and the ribosomal RNA processing enzyme RNase MRP. Rpp14, by contrast, exhibits no significant homology to any known yeast gene. Thus, human RNase P differs in the details of its protein composition, and perhaps in the functions of some of these proteins, from the yeast enzyme.
在HeLa细胞中，tRNA加工酶核糖核酸酶P（RNase P）由一个与至少八个蛋白质亚基（hPop1、Rpp14、Rpp20、Rpp25、Rpp29、Rpp30、Rpp38和Rpp40）相关联的RNA分子组成。其中五个蛋白质（hPop1p、Rpp20、Rpp30、Rpp38和Rpp40）已得到部分表征。在此，我们报告Rpp14和Rpp29的cDNA克隆及免疫生化分析。针对重组Rpp14和Rpp29产生的兔多克隆抗体可识别HeLa细胞中的相应抗原，并沉淀出具有催化活性的RNase P。Rpp29与酵母核RNase P及核糖体RNA加工酶RNase MRP的一个亚基Pop4p具有23%的同一性。相比之下，Rpp14与任何已知的酵母基因均无明显同源性。因此，人类RNase P在蛋白质组成细节上，或许在其中一些蛋白质的功能上，与酵母酶有所不同。
