|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Department of Biochemistry, Nijmegen Center for Molecular Life Sciences, Radboud University Nijmegen, NL-6500 HB, Nijmegen, The Netherlands
RNase MRP is a eukaryotic endoribonuclease involved in nucleolar and mitochondrial RNA processing events. RNase MRP is a ribonucleoprotein particle, which is structurally related to RNase P, an endoribonuclease involved in pre-tRNA processing. Most of the protein components of RNase MRP have been reported to be associated with RNase P as well. In this study we determined the association of these protein subunits with the human RNase MRP and RNase P particles by glycerol gradient sedimentation and coimmunoprecipitation. In agreement with previous studies, RNase MRP sedimented at 12S and 6080S. In contrast, only a single major peak was observed for RNase P at 12S. The analysis of individual protein subunits revealed that hPop4 (also known as Rpp29), Rpp21, Rpp20, and Rpp25 only sedimented in 12S fractions, whereas hPop1, Rpp40, Rpp38, and Rpp30 were also found in 6080S fractions. In agreement with their cosedimentation with RNase P RNA in the 12S peak, coimmunoprecipitation with VSV-epitope-tagged protein subunits revealed that hPop4, Rpp21, and in addition Rpp14 preferentially associate with RNase P. These data show that hPop4, Rpp21, and Rpp14 may not be associated with RNase MRP. Furthermore, Rpp20 and Rpp25 appear to be associated with only a subset of RNase MRP particles, in contrast to hPop1, Rpp40, Rpp38, and Rpp30 (and possibly also hPop5), which are probably associated with all RNase MRP complexes. Our data are consistent with a transient association of Rpp20 and Rpp25 with RNase MRP, which may be inversely correlated to its involvement in pre-rRNA processing.
Keywords: RNase MRP; RNase P; snoRNP; RNA processing; ribonuclease; ribonucleoprotein
![]()
CiteULike
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
N. Jarrous and R. Reiner Human RNase P: a tRNA-processing enzyme and transcription factor Nucleic Acids Res., June 28, 2007; 35(11): 3519 - 3524. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. J.M. Welting, F. M.A. Peters, S. M.M. Hensen, N. L. van Doorn, B. J. Kikkert, J. M.H. Raats, W. J. van Venrooij, and G. J.M. Pruijn Heterodimerization regulates RNase MRP/RNase P association, localization, and expression of Rpp20 and Rpp25 RNA, January 1, 2007; 13(1): 65 - 75. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Rosenblad, M. D. Lopez, P. Piccinelli, and T. Samuelsson Inventory and analysis of the protein subunits of the ribonucleases P and MRP provides further evidence of homology between the yeast and human enzymes Nucleic Acids Res., October 6, 2006; 34(18): 5145 - 5156. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |