This Article Full Text Full Text (PDF) Other Versions of this Article: JB.00147-08v1 190/10/3774    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Google Scholar Articles by Yang, J. Articles by Schesser, K. PubMed PubMed Citation Articles by Yang, J. Articles by Schesser, K.

RNase E Regulates the Yersinia Type 3 Secretion System

Department of Microbiology and Immunology,¹ Department of Biochemistry and Molecular Biology, University of Miami, Miller School of Medicine, Miami, Florida²

Received 28 January 2008/ Accepted 12 March 2008

Yersinia spp. use a type 3 secretion system (T3SS) to directly inject six proteins into macrophages, and any impairment of this process results in a profound reduction in virulence. We previously showed that the exoribonuclease polynucleotide phosphorylase (PNPase) was required for optimal T3SS functioning in Yersinia pseudotuberculosis and Yersinia pestis. Here we report that Y. pseudotuberculosis cells with reduced RNase E activity are likewise impaired in T3SS functioning and that phenotypically they resemble pnp cells. RNase E does not affect expression levels of the T3SS substrates but instead, like PNPase, regulates a terminal event in the secretion pathway. This similarity, together with the fact that RNase E and PNPase can be readily copurified from Y. pseudotuberculosis cell extracts, suggests that these two RNases regulate T3SS activity through a common mechanism. This is the first report that RNase E activity impacts the T3SS as well as playing a more general role in infectivity.

Published ahead of print on 21 March 2008.