Functional conservation of RNase III-like enzymes: studies on a Vibrio vulnificus ortholog of Escherichia coli RNase III.
Bacterial ribonuclease III (RNase III) belongs to the RNase III enzyme family, which plays a pivotal role in controlling mRNA stability and RNA processing in both prokaryotes and eukaryotes. In the Vibrio vulnificus genome, one open reading frame encodes a protein homologous to E. coli RNase III, designated Vv-RNase III, which has 77.9 % amino acid identity to E. coli RNase III. Here, we report that Vv-RNase III has the same cleavage specificity as E. coli RNase III in vivo and in vitro. Expressing Vv-RNase III in E. coli cells deleted for the RNase III gene (rnc) restored normal rRNA processing and, consequently, growth rates of these cells comparable to wild-type cells. In vitro cleavage assays further showed that Vv-RNase III has the same cleavage activity and specificity as E. coli RNase III on RNase III-targeted sequences of corA and mltD mRNA. Our findings suggest that RNase III-like proteins have conserved cleavage specificity across bacterial species.
Department of Life Science, Chung-Ang University, 84 Heuksok-Ro, Dongjak-Gu, Seoul, 156-756, Republic of Korea.
Minho
M
Lee
Sangmi
S
Ahn
Boram
B
Lim
Dong-Ho
DH
Lee
Kangseok
K
Lee
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D043244:Ribonuclease III / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D041261:Vibrio vulnificus / Q000201:enzymology* / Q000235:genetics
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D012333:RNA, Messenger; D043244:Ribonuclease III; C468366:ribonuclease III, E coli