6. Histone acetylation is generally associated with gene activation. What is the primary molecular mechanism underlying this phenomenon?
(A) Acetylation neutralizes the positive charge on lysine residues, weakening the electrostatic attraction to the negatively charged DNA backbone and creating a more open chromatin structure.
(B) The addition of acetyl groups increases hydrophobicity, thereby strengthening the Van der Waals forces between histones and DNA to stabilize the nucleosome.
(C) Acetylation acts as an enzymatic cofactor that directly catalyzes the phosphorylation of RNA Polymerase II to initiate transcription elongation.
(D) Acetyl marks specifically recruit DNA methyltransferases to promote CpG island methylation, effectively locking the gene in a silenced state.
(E) Acetylation serves as an irreversible signal that targets histones for degradation via the ubiquitin-proteasome pathway, clearing the DNA for transcription.