학술논문
Monitoring substrate enables real-time regulation of a protein localization pathway
Physiology & Biochemistry
Physiology & Biochemistry
Document Type
Report
Author
Source
FEMS Microbiology Letters. June 1, 2018, Vol. 365 Issue 11, p1K, 11 p.
Subject
Language
English
ISSN
0378-1097
Abstract
PROTEIN LOCALIZATION PATHWAYS IN BACTERIA One of the critical issues in the processes of protein localization is how proteins get translocated across or integrated into the membrane (Wickner and Schekman [...]
Protein localization machinery supports cell survival and physiology, suggesting the potential importance of its expression regulation. Here, we summarize a remarkable scheme of regulation, which allows real-time feedback regulation of the machinery expression. A class of regulatory nascent polypeptides, called monitoring substrates, undergoes force-sensitive translation arrest. The resulting ribosome stalling on the mRNA then affects mRNA folding to expose the ribosome-binding site of the downstream target gene and upregulate its translation. The target gene encodes a component of the localization machinery, whose physical action against the monitoring substrate leads to arrest cancellation. Thus, this scheme of feedback loop allows the cell to adjust the amount of the machinery to correlate inversely with the effectiveness of the process at a given moment. The system appears to have emerged late in evolution, in which a narrow range of organisms selected a distinct monitoring substrate-machinery combination. Currently, regulatory systems of SecM-SecA, VemP-SecDF2 and MifM-YidC2 are known to occur in different bacterial species. Keywords: ribosome stalling; nascent polypeptide; SecM; VemP; MifM; translation arrest
Protein localization machinery supports cell survival and physiology, suggesting the potential importance of its expression regulation. Here, we summarize a remarkable scheme of regulation, which allows real-time feedback regulation of the machinery expression. A class of regulatory nascent polypeptides, called monitoring substrates, undergoes force-sensitive translation arrest. The resulting ribosome stalling on the mRNA then affects mRNA folding to expose the ribosome-binding site of the downstream target gene and upregulate its translation. The target gene encodes a component of the localization machinery, whose physical action against the monitoring substrate leads to arrest cancellation. Thus, this scheme of feedback loop allows the cell to adjust the amount of the machinery to correlate inversely with the effectiveness of the process at a given moment. The system appears to have emerged late in evolution, in which a narrow range of organisms selected a distinct monitoring substrate-machinery combination. Currently, regulatory systems of SecM-SecA, VemP-SecDF2 and MifM-YidC2 are known to occur in different bacterial species. Keywords: ribosome stalling; nascent polypeptide; SecM; VemP; MifM; translation arrest