Signal sequence cleavage of peptidyl-tRNA prior to release from the ribosome and translocon.
Many secretory polypeptides undergo cleavage of their signal sequence. In this study, we observed and quantitated the presence of a tRNA-bound, ribosome-associated polypeptide subpopulation present in vitro. This subpopulation was accessible to signal peptidase on ribosome-associated polypeptides longer than 114 amino acids. This demonstrates that it is possible for a peptidyl-tRNA species, in the midst of translation, to be processed by the endoplasmic reticulum signal peptidase implying that the peptidase is closely associated with the mammalian translocon.
Wollenberg
Michael S
MS
Laboratory of Cellular Biophysics, Rockefeller University, New York, New York 10021, USA.
Simon
Sanford M
SM
D004721:Endoplasmic Reticulum / Q000378:metabolism; D008970:Molecular Weight; D014176:Protein Biosynthesis; D021382:Protein Sorting Signals / Q000502:physiology*; D021381:Protein Transport; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
D021382:Protein Sorting Signals; D012346:RNA, Transfer, Amino Acyl; C019037:tRNA, peptidyl-; D001618:beta-Lactamases