Title of article :
Importance of the +73/294 Interaction in Escherichia coli RNase P RNA Substrate Complexes for Cleavage and Metal Ion Coordination
Author/Authors :
Mathias Br?nnvall، نويسنده , , B.M.Fredrik Pettersson، نويسنده , , Leif A. Kirsebom، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2003
Pages :
13
From page :
697
To page :
709
Abstract :
We have studied an interaction, the “73/294-interaction”, between residues 294 in M1 RNA (the catalytic subunit of Escherichia coli RNase P) and +73 in the tRNA precursor substrate. The 73/294-interaction is part of the “RCCA-RNase P RNA interaction”, which anchors the 3′ R+73CCA-motif of the substrate to M1 RNA (interacting residues underlined). Considering that in a large fraction of tRNA precursors residue +73 is base-paired to nucleotide −1 immediately 5′ of the cleavage site, formation of the 73/294-interaction results in exposure of the cleavage site. We show that the nature/orientation of the 73/294-interaction is important for cleavage site recognition and cleavage efficiency. Our data further suggest that this interaction is part of a metal ion-binding site and that specific chemical groups are likely to act as ligands in binding of Mg2+ or other divalent cations important for function. We argue that this Mg2+ is involved in metal ion cooperativity in M1 RNA-mediated cleavage. Moreover, we suggest that the 73/294-interaction operates in concert with displacement of residue −1 in the substrate to ensure efficient and correct cleavage. The possibility that the residue at −1 binds to a specific binding surface/pocket in M1 RNA is discussed. Our data finally rationalize why the preferred residue at position 294 in M1 RNA is U.
Keywords :
RNase P , tRNA precursors , tRNA processing , ribozyme , Divalent metal ions
Journal title :
Journal of Molecular Biology
Serial Year :
2003
Journal title :
Journal of Molecular Biology
Record number :
1242324
Link To Document :
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