Mutual interactions between subunits of the human RNase MRP ribonucleoprotein complex.
The eukaryotic ribonuclease for mitochondrial RNA processing (RNase MRP) is mainly located in the nucleoli and belongs to the small nucleolar ribonucleoprotein (snoRNP) particles. RNase MRP is involved in the processing of pre-rRNA and the generation of RNA primers for mitochondrial DNA replication. A closely related snoRNP, which shares protein subunits with RNase MRP and contains a structurally related RNA subunit, is the pre-tRNA processing factor RNase P. Up to now, 10 protein subunits of these complexes have been described, designated hPop1, hPop4, hPop5, Rpp14, Rpp20, Rpp21, Rpp25, Rpp30, Rpp38 and Rpp40. To get more insight into the assembly of the human RNase MRP complex we studied protein-protein and protein-RNA interactions by means of GST pull-down experiments. A total of 19 direct protein-protein and six direct protein-RNA interactions were observed. The analysis of mutant RNase MRP RNAs showed that distinct regions are involved in the direct interaction with protein subunits. The results provide insight into the way the protein and RNA subunits assemble into a ribonucleoprotein particle. Based upon these data a new model for the architecture of the human RNase MRP complex was generated.
Welting
Tim J M
TJ
Department of Biochemistry, Nijmegen Center for Molecular Life Sciences, University of Nijmegen, Nijmegen, The Netherlands.
van Venrooij
Walther J
WJ
Pruijn
Ger J M
GJ
D001483:Base Sequence; D004722:Endoribonucleases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D021122:Protein Subunits / Q000737:chemistry* / Q000378:metabolism*; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion
D046911:Macromolecular Substances; D021122:Protein Subunits; D012313:RNA; D004722:Endoribonucleases; C058330:mitochondrial RNA-processing endoribonuclease