Publications by authors named "Ssu-Jean Chang"
Regulation of ribonuclease E activity by the L4 ribosomal protein of Escherichia coli.
Proc Natl Acad Sci U S A
January 2009
Article Synopsis
- Certain ribosomal proteins, like L4, have functions beyond their role in protein synthesis, specifically in regulating RNA degradation in E. coli.
- L4 interacts with RNase E, inhibiting its cleavage activity, which leads to increased mRNA stability and affects plasmid DNA replication.
- The study shows that L4's influence results in significant changes in the abundance of various stress response mRNAs, suggesting its role in helping bacteria adapt to stressful environments.
Recently, two sequence-specific cleavage sites were found in the ceiE7 gene of the cea-cei-cel polycistronic transcript from the ColE7 operon. The crystal structure of the ColE7 immunity protein (ImE7) suggested that a novel ribonuclease active site is created at the interface of the dimeric structure of the protein. Frame shift mutation of the ceiE7 gene and mutation of histidine residues at the putative active site of the dimeric ImE7 protein respectively abolished and significantly reduced the observed ribonucleolytic cleavage indicating that the dimeric ImE7 protein is indeed involved in this sequence-specific cleavage at the ceiE7 mRNA.
View Article and Find Full Text PDFCharacterization of the specific cleavage of ceiE7-mRNA of the bactericidal ColE7 operon.
Biochem Biophys Res Commun
December 2002
Posttranscriptional control of the bactericidal ColE7 operon has been implicated by a feedback endonucleolytic cleavage of its own mRNA. The cleavage site has been located at the coding region of ceiE7, the second cistron of the ColE7 cea-cei-cel polycistronic transcript. Interestingly, Im7 protein, the translation product of ceiE7, is required for the specific cleavage.
View Article and Find Full Text PDF