Question

Question 31 (2 points) Which of the following is likely to decrease expression of a eukaryotic gene? (Select all that apply) Adding methyl groups to CpG islands Adding acetyl groups to histones Removing the poly A tail from mRNAs Increasing the amount of TFID or TBP adding enhancer sequences to the regulatory region adding a 5' methyl guanine cap

Answer 1

Adding methyl groups to CpG islands decreases expression of an eukaryotic gene.

Normally CpG islands are in nonmethylated state while the whole genome is heavily methylated. Methylation of CpG islands silence the gene expression.

Other options like

• Histone acetylation
• Removal of poly A tail from mRNAs
• Increasing the amount of TFIID or TBP
• Adding enhancer sequences to the regulatory region
• Adding a 5’methyl guanine cap

will only increase the gene expression.