Conserved mycobacteriophage protein uses structural mimicry to displace host initiation factors
Compact viral genomes encode sophisticated strategies to reprogram host gene expression, often by co-opting rather than replacing the host RNA polymerase. How bacteriophages achieve such control in Mycobacteria remains largely unknown. Here, time-resolved interaction proteomics of mycobacteriophage D29 infection identifies a conserved two-protein module, gp53-gp52, that binds the host RNA…
A team of researchers has discovered how a conserved protein module of mycobacteriophage D29 employs structural mimicry to displace host initiation factors during infection of Mycobacteria. The protein module, gp53-gp52, was identified through time-resolved interaction proteomics of the phage infection process. Affinity purification and native mass spectrometry confirmed the association of both gp53 and gp52 with the host RNA polymerase.
Structural modeling revealed that gp53 occupies the sigma-binding surface of the RNA polymerase, mimicking the engagement of the host sigma factor. This module is found throughout Cluster A mycobacteriophages, existing as either a fused or split genomic arrangement. The findings suggest that the displacement of the host sigma factor represents a mechanism of transcriptional takeover by viruses of mycobacteria, showcasing how a compact viral module can repurpose essential host molecular machinery.
Written by urgent.news from bioRxiv's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
