Article

Global Identification of New Substrates for the Yeast Endoribonuclease, RNase Mitochondrial RNA Processing (MRP).

SUNY Upstate Medical University, United States
Journal of Biological Chemistry (Impact Factor: 4.6). 09/2012; DOI: 10.1074/jbc.M112.389023
Source: PubMed

ABSTRACT RNase MRP is an essential, evolutionarily conserved endoribonuclease composed of 10 different protein subunits and a single RNA. RNase MRP has established roles in multiple pathways including: ribosome biogenesis, cell cycle regulation, and mitochondrial DNA replication. Although each of these functions is important to cell growth additional functions may exist given the essential nature of the complex. In order to identify novel RNase MRP substrates, we have utilized RIP-chip (RNA Immuno-Precipitation and microarray chip analysis) to identify RNA that physically associates with RNase MRP. We identified several new potential substrates for RNase MRP including a cell-cycle regulated transcript, CTS1, the yeast homolog of the mammalian p27(Kip1), SIC1, and the U2 RNA component of the spliceosome. In addition, we found RNase MRP to be involved in the regulation of the TY1 transposon RNA. These results reinforce and broaden the role of RNase MRP in cell cycle regulation and help to identify new roles of this endoribonuclease.

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