Cyanophage MarR-type transcription factor regulates host RNase E expression

ABSTRACT: The marine picocyanobacterium Prochlorococcus contributes significantly to global primary production, and its abundance and diversity is shaped in part by viral infection. Here, we identified a cyanophage-encoded MarR-type transcription factor that induces gene expression of host Prochlorococcus MED4 endoribonuclease (RNase) E during phage infection. The increase in rne transcript levels relies on the phage (p)MarR-mediated activation of an alternative promoter that gives rise to a truncated, yet, enzymatically fully functional RNase E isoform. In this study, we demonstrate that pMarR binds to an atypical activator site downstream of the transcriptional start site and that binding is enhanced in the presence of Ca2+ ions. Furthermore, we show that dimeric pMaR interacts with the α subunit of RNA polymerase, and we identified amino acid residues S66, R67 and G106, which are important for Ca2+ binding, DNA binding and dimerization of pMarR, respectively.

INSTRUMENT(S):

ORGANISM(S): Prochlorococcus Marinus Subsp. Pastoris Str. Ccmp1986

TISSUE(S): Cell Suspension Culture, Photosynthetic Cell

SUBMITTER: Frederik Sommer  

LAB HEAD: Dr. Claudia Steglich

PROVIDER: PXD035458 | Pride | 2023-03-11

REPOSITORIES: Pride