Does the MS2 L protein work with E. coli host factors?

Abstract

MS2 is a small single stranded RNA bacteriophage that escapes its infected Escherichia coli host through an L protein‐driven lysis mechanism. The L protein consists of 75 amino acids, with a hydrophilic N‐terminal that contains mainly basic residues and a hydrophobic C‐terminal end. Prior studies have shown that the L protein is necessary for the cell to lyse, however it is not known if L alone is sufficient for cell lysis. In our laboratory we have shown that expression of the L protein in the absence of other viral proteins causes E. coli lysis within 40 minutes of expression. Further, the actual mechanism for lysis is not completely understood and potentially requires a protein‐protein interaction with E. Coli host factors. Recent studies by Chamakura et. al [Journal of Bacteriology, 12, 199 (2017)] using a genetic screen identified DnaJ, a chaperone protein, as a host factor involved in the lysis mechanism. However, this study did not describe a direct protein‐protein interaction between L and DnaJ. Thus, the question remains whether DnaJ along with MS2 L is necessary and sufficient for lysis, or are there additional host proteins involved? In order to answer this question and investigate host protein interactions using a biochemical approach, a hemagglutinin epitope tag (HA) will be inserted into a plasmid containing the MS2 L gene and an arabinose‐inducible promoter. Once transformed into E. coli, the HA tagged L protein can be detected using a Western Blot and purified by immunoprecipitation. Using these methods, it is expected that any host protein that interacts with the L protein will be co‐immunoprecipitated. Future studies will use mass spectrometry to identify these co‐immunoprecipitated proteins.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.