How is sequential gene expression controlled in bacterial viruses like E.coli phages T7 and T4 and Bacillus subtilis phage SP01?
A) Modifying the DNA topology
B) Sequential binding of a series of repressor molecules
C) Modifying the specificity of RNA polymerase for different promoter sequences
D) Sequential binding of inducer molecules to the repressor
E) None of these are correct.

Question

Quizplus · Accepted Answer

Sequential gene expression in bacterial viruses like E.coli phages T7 and T4 and Bacillus subtilis phage SP01 is controlled by modifying the specificity of RNA polymerase for different promoter sequences. The viral gene expression is regulated by a cascade of early and late phage-specific proteins that interact with host and phage proteins to control the timing and order of gene expression. This involves the binding of a series of specific transcription factors to the promoter region of each gene, which allows RNA polymerase to recognize and bind to the promoter to initiate transcription. The specificity of RNA polymerase for different promoter sequences is altered by the presence of these transcription factors, allowing for sequential gene expression in the appropriate order.

How Is Sequential Gene Expression Controlled in Bacterial Viruses Like