Protein factors associated with the SsrA.SmpB tagging and ribosome rescue complex.
SsrA RNA acts as a tRNA and mRNA to modify proteins whose synthesis on ribosomes has stalled. Such proteins are marked for degradation by addition of peptide tags to their C termini in a reaction mediated by SsrA RNA and SmpB, a specific SsrA-RNA binding protein. Evidence is presented here for the existence of a larger ribonucleoprotein complex that contains ribosomal protein S1, phosphoribosyl pyrophosphate synthase, RNase R, and YfbG in addition to SsrA RNA and SmpB. Biochemical, genetic, and phylogenetic results suggest potential roles for some of these factors in various stages of the ribosome rescue and tagging process and/or the presence of functional interactions between one or more of these proteins and SsrA.
Karzai
A W
AW
Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Sauer
R T
RT
D001483:Base Sequence; D005822:Genetic Vectors; D006639:Histidine / Q000235:genetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012261:Ribonucleoproteins / Q000378:metabolism*; D012268:Ribose-Phosphate Pyrophosphokinase / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D016324:Sequence Tagged Sites; D012995:Solubility
D012329:RNA, Bacterial; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D012261:Ribonucleoproteins; D012269:Ribosomal Proteins; C015494:ribosomal protein S1; C430328:small protein B; C096222:tmRNA; D006639:Histidine; D012343:RNA, Transfer; D012268:Ribose-Phosphate Pyrophosphokinase