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Structure and function of the native and recombinant mitochondrial MRP1/MRP2 complex from Trypanosoma brucei.

ABSTRACT: The mitochondrial RNA-binding proteins (MRP) 1 and 2 play a regulatory role in RNA editing and putative role(s) in RNA processing in Trypanosoma brucei. Here, we report the purification of a high molecular weight protein complex consisting solely of the MRP1 and MRP2 proteins from the mitochondrion of T. brucei. The MRP1/MRP2 complex natively purified from T. brucei and the one reconstituted in Escherichia coli in vivo bind guide (g) RNAs and pre-mRNAs with dissociation constants in the nanomolar range, and efficiently promote annealing of pre-mRNAs with their cognate gRNAs. In addition, the MRP1/MRP2 complex stimulates annealing between two non-cognate RNA molecules suggesting that along with the cognate duplexes, spuriously mismatched RNA hybrids may be formed at some rate in vivo. A mechanism of catalysed annealing of gRNA/pre-mRNA by the MRP1/MRP2 complex is proposed.

SUBMITTER: Zikova A

PROVIDER: S-EPMC2492832 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Structure and function of the native and recombinant mitochondrial MRP1/MRP2 complex from Trypanosoma brucei.

Zíková Alena A Kopecná Jana J Schumacher Maria A MA Stuart Kenneth K Trantírek Lukás L Lukes Julius J

International journal for parasitology 20080126 8-9

The mitochondrial RNA-binding proteins (MRP) 1 and 2 play a regulatory role in RNA editing and putative role(s) in RNA processing in Trypanosoma brucei. Here, we report the purification of a high molecular weight protein complex consisting solely of the MRP1 and MRP2 proteins from the mitochondrion of T. brucei. The MRP1/MRP2 complex natively purified from T. brucei and the one reconstituted in Escherichia coli in vivo bind guide (g) RNAs and pre-mRNAs with dissociation constants in the nanomola ...[more]

PMID: 18295767

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