A Cryptic Prophage Transcription Factor Drives Phenotypic Changes via Host Gene Regulation

Area of Science:

• Bacteriology and Molecular Biology
• Genomics and Gene Regulation
• Microbial Genetics

Background:

• Cryptic prophages (CPs) are integrated bacteriophage DNA within bacterial genomes.
• CPs can encode proteins affecting host cell phenotypes.
• The regulatory role of CP-encoded transcription factors (TFs) on host gene expression is largely unexplored.

Purpose of the Study:

• To investigate the impact of CP-encoded TFs on bacterial host gene regulation and physiology.
• To identify host genes regulated by DicC, a TF from the Qin prophage in Escherichia coli.

Main Methods:

• Identification of host gene targets regulated by the DicC TF.
• Analysis of DicC-regulated genes in relation to known host phenotypes.
• Assessment of the DicC-induced growth defect's independence from other Qin prophage genes.

Main Results:

• Hundreds of host genes were identified as being regulated by DicC.
• DicC-regulated targets were linked to known phenotypes associated with Qin prophage induction.
• A DicC-induced growth defect was found to be largely independent of other Qin prophage genes.

Conclusions:

• CP-encoded TFs play a significant role in controlling bacterial host gene expression.
• DicC actively modulates Escherichia coli physiology through extensive gene regulation.
• CP TFs represent a greater influence on bacterial gene expression than previously understood.