Srisawat Chatchawan, Houser-Scott Felicia, Bertrand Edouard, Xiao Shaohua, Singer Robert H, Engelke David R
Department of Biological Chemistry, University of Michigan, Ann Arbor 48109-0606, USA.
RNA. 2002 Oct;8(10):1348-60. doi: 10.1017/s1355838202027048.
The RNA-protein subunit assembly of nuclear RNase P was investigated by specific isolation and characterization of the precursor and mature forms of RNase P using an RNA affinity ligand. Pre-RNase P was as active in pre-tRNA cleavage as mature RNase P, although it contained only seven of the nine proteins found in mature RNase P. Pop3p and Rpr2p were not required for maturation of the RPR1 RNA subunit and virtually absent from pre-RNase P, implying that they are dispensable for pre-tRNA substrate recognition and cleavage. The RNase P subunit assembly is likely to occur in the nucleolus, where both precursor and mature forms of RNase P RNA are primarily localized. The results provide insight into assembly of nuclear RNase P, and suggest pre-tRNA substrate recognition is largely determined by the RNA subunit.
利用RNA亲和配体对核酶RNase P的前体和成熟形式进行特异性分离和表征，研究了核RNase P的RNA-蛋白质亚基组装。前体RNase P在切割前体tRNA方面与成熟RNase P一样活跃，尽管它只含有成熟RNase P中发现的九种蛋白质中的七种。Pop3p和Rpr2p对于RPR1 RNA亚基的成熟不是必需的，并且在前体RNase P中几乎不存在，这意味着它们对于前体tRNA底物的识别和切割是可有可无的。RNase P亚基组装可能发生在核仁中，RNase P RNA的前体和成熟形式主要定位于此。这些结果为核RNase P的组装提供了见解，并表明前体tRNA底物的识别很大程度上由RNA亚基决定。
