The particular amino acid sequence in the helix-turn-helix domain of a regulatory protein
A)determines which DNA sequence is recognized by this protein.
B)determines which RNA polymerase will bind to the promoter.
C)controls the catalytic activity of an enzyme.
D)allows this protein to change shape when it binds cAMP.

Question

Quizplus · Accepted Answer

The helix-turn-helix domain of a regulatory protein is involved in binding to the DNA molecule at a specific sequence. The amino acid sequence of this domain determines which DNA sequence will be recognized by the protein, allowing it to activate or repress gene expression at the appropriate target site. This is a critical mechanism of gene regulation in both prokaryotes and eukaryotes.

The Particular Amino Acid Sequence in the Helix-Turn-Helix Domain of a Regulatory