Jarrous Nayef, Reiner Robert
Department of Molecular Biology, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
Nucleic Acids Res. 2007;35(11):3519-24. doi: 10.1093/nar/gkm071. Epub 2007 May 5.
Ribonuclease P (RNase P) has been hitherto well known as a catalytic ribonucleoprotein that processes the 5' leader sequence of precursor tRNA. Recent studies, however, reveal a new role for nuclear forms of RNase P in the transcription of tRNA genes by RNA polymerase (pol) III, thus linking transcription with processing in the regulation of tRNA gene expression. However, RNase P is also essential for the transcription of other small noncoding RNA genes, whose precursor transcripts are not recognized as substrates for this holoenzyme. Accordingly, RNase P can act solely as a transcription factor for pol III, a role that seems to be conserved in eukarya.
核糖核酸酶P（RNase P）迄今一直作为一种催化核糖核蛋白而为人熟知，它负责加工前体tRNA的5'前导序列。然而，最近的研究揭示了核形式的RNase P在RNA聚合酶（pol）III转录tRNA基因过程中的新作用，从而在tRNA基因表达调控中将转录与加工联系起来。然而，RNase P对于其他小非编码RNA基因的转录也是必不可少的，其前体转录本不被识别为该全酶的底物。因此，RNase P可以单独作为pol III的转录因子，这一作用在真核生物中似乎是保守的。
