As a General Principle of Gene Regulation Through Operons,regulatory Genes

Question

As a general principle of gene regulation through operons,regulatory genes encode
A) trans-acting proteins that interact with cis-acting DNA elements.
B) cis-acting proteins that interact with cis-acting DNA elements.
C) cis-acting proteins that interact with trans-acting DNA elements.
D) trans-acting proteins that interact with trans-acting DNA elements.
E) trans-acting proteins that act autonomously.

Accepted Answer

Regulatory genes typically encode trans-acting proteins that interact with cis-acting DNA elements on the same or different DNA molecules. This allows the protein to control the expression of multiple genes within an operon or even across different operons. Cis-acting proteins would only be able to regulate genes on the same DNA molecule, while trans-acting proteins that interact with trans-acting DNA elements or act autonomously would not be able to specifically regulate genes within an operon.