TY - JOUR
T1 - Binding site of the M-domain of human protein SRP54 determined by systematic site-directed mutagenesis of signal recognition particle RNA
AU - Gowda, Krishne
AU - Chittenden, Kimberly
AU - Zwieb, Christian
N1 - Funding Information:
We thank Shaun D. Black for critical reading of the script and Kerfoot P. Walker III for exceptional technical help. This work was supported by NIH grant GM-49034 to C.Z.
PY - 1997
Y1 - 1997
N2 - The interaction of protein SRP54M from the human signal recognition particle with SRP RNA was studied by systematic site-directed mutagenesis of the RNA molecule. Protein binding sites were identified by the analysis of mutations that removed individual SRP RNA helices or disrupted helical sections in the large SRP domain. The strongest effects on the binding activity of a purified polypeptide that corresponds to the methionine-rich domain of SRP54 (SRP54M) were caused by changes in helix 8 of the SRP RNA. Binding of protein SRP19 was diminished significantly by mutations in helix 6 and was stringently required for SRP54M to associate. Unexpectedly, mutant RNA molecules that resembled bacterial SRP RNAs were incapable of interaction with SRP54M, showing that protein SRP19 has an essential and direct role in the formation of the ternary complex with SRP54 and SRP RNA. Our findings provide an example for how, in eukaryotes, an RNA function has become protein dependent.
AB - The interaction of protein SRP54M from the human signal recognition particle with SRP RNA was studied by systematic site-directed mutagenesis of the RNA molecule. Protein binding sites were identified by the analysis of mutations that removed individual SRP RNA helices or disrupted helical sections in the large SRP domain. The strongest effects on the binding activity of a purified polypeptide that corresponds to the methionine-rich domain of SRP54 (SRP54M) were caused by changes in helix 8 of the SRP RNA. Binding of protein SRP19 was diminished significantly by mutations in helix 6 and was stringently required for SRP54M to associate. Unexpectedly, mutant RNA molecules that resembled bacterial SRP RNAs were incapable of interaction with SRP54M, showing that protein SRP19 has an essential and direct role in the formation of the ternary complex with SRP54 and SRP RNA. Our findings provide an example for how, in eukaryotes, an RNA function has become protein dependent.
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U2 - 10.1093/nar/25.2.388
DO - 10.1093/nar/25.2.388
M3 - Article
C2 - 9016569
AN - SCOPUS:0030736479
VL - 25
SP - 388
EP - 394
JO - Nucleic Acids Research
JF - Nucleic Acids Research
SN - 0305-1048
IS - 2
ER -