This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Basics of DNA, Subject name: Biochemistry
Sumoylation of histones proteins is associated with 
Select and explain. 
A. Activation of gene transcription, B. Condensation of chromosome, C. Transcription repression, D. Inactivation of gene transcription
C: Transcription repression
Answer: C: Transcription repression 
Explanation: Sumoylation of histones is associated with Transcription repression Histone post-translational modifications & their role: Post-translational modifications Role Acetylation of histones H3 and H4 Activation or inactivation of gene transcription Acetylation of core histones Chromosomal assembly during DNA replication Phosphorylation of histone H1 Condensation of chromosomes during the replication cycle ADP-ribosylation of histone DNA repair Methylation of histone Activation and repression of gene transcription Mono-ubiquitylation Gene activation, repression, and heterochromatic gene silencing Sumoylation of histones Transcription repression