Download MendeleyStructure of the nuclease subunit of human mitochondrial RNase P.
Reinhard, L., Sridhara, S., Hallberg, B.M.(2015) Nucleic Acids Res 43: 5664-5672
- PubMed: 25953853
- DOI: https://doi.org/10.1093/nar/gkv481
- Primary Citation of Related Structures:
4XGL, 4XGM - PubMed Abstract:
Mitochondrial RNA polymerase produces long polycistronic precursors that contain the mRNAs, rRNAs and tRNAs needed for mitochondrial translation. Mitochondrial RNase P (mt-RNase P) initiates the maturation of the precursors by cleaving at the 5' ends of the tRNAs. Human mt-RNase P is only active as a tripartite complex (mitochondrial RNase P proteins 1-3; MRPP1-3), whereas plant and trypanosomal RNase Ps (PRORPs)-albeit homologous to MRPP3-are active as single proteins. The reason for this discrepancy has so far remained obscure. Here, we present the crystal structure of human MRPP3, which features a remarkably distorted and hence non-productive active site that we propose will switch to a fully productive state only upon association with MRPP1, MRPP2 and pre-tRNA substrate. We suggest a mechanism in which MRPP1 and MRPP2 both deliver the pre-tRNA substrate and activate MRPP3 through an induced-fit process.
Organizational Affiliation:
Department of Cell and Molecular Biology, Karolinska Institutet, 17177 Stockholm, Sweden Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology, DESY-Campus, 22607 Hamburg, Germany.
