Proteomic identification of tmRNA substrates.

Proc Natl Acad Sci U S A

Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA.

Published: October 2007

AI Article Synopsis

  • * Mutations that impair tmRNA function lead to growth issues, particularly in Caulobacter crescentus, which experiences delays in DNA replication initiation and overall cell cycle disruption.
  • * A study identified 73 C. crescentus proteins tagged by tmRNA that play roles in DNA processes, suggesting that the failure of tmRNA activity leads to misregulation of these critical proteins, impacting DNA replication timing.

Article Abstract

The tmRNA-SmpB system releases ribosomes stalled on truncated mRNAs and tags the nascent polypeptides to target them for proteolysis. In many species, mutations that disrupt tmRNA activity cause defects in growth or development. In Caulobacter crescentus cells lacking tmRNA activity there is a delay in the initiation of DNA replication, which disrupts the cell cycle. To understand the molecular basis for this phenotype, 73 C. crescentus proteins were identified that are tagged by tmRNA under normal growth conditions. Among these substrates, proteins involved in DNA replication, recombination, and repair were overrepresented, suggesting that misregulation of these factors in the absence of tmRNA activity might be responsible for the delay in initiation of DNA replication. Analysis of the tagging sites within these substrates revealed a conserved nucleotide motif 5' of the tagging site, which is required for wild-type tmRNA tagging.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2040454PMC
http://dx.doi.org/10.1073/pnas.0707671104DOI Listing

Publication Analysis

Top Keywords

tmrna activity
12
dna replication
12
delay initiation
8
initiation dna
8
tmrna
6
proteomic identification
4
identification tmrna
4
tmrna substrates
4
substrates tmrna-smpb
4
tmrna-smpb system
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!