Molecular Biology and Applied Genetics: Control of Gene Expression

This article discusses the three main levels of gene expression control: transcriptional control, translational control, and post-translational control.

Questions:

• What are the three main levels of gene expression control?
• How does transcriptional control affect the amount of gene product realized?
• What factors influence the life expectancy of mRNA molecules?
• How does post-translational control affect the function of proteins?

Answers:

• The three main levels of gene expression control are transcriptional control, translational control, and post-translational control.
• Transcriptional control affects the amount of gene product realized by regulating the rate at which mRNA is transcribed from DNA.
• The life expectancy of mRNA molecules can vary, depending on the length of the mRNA molecule and the presence of non-coding segments at the 3′ cap and 5′ poly-A tail ends.
• Post-translational control affects the function of proteins by modifying their structure or by regulating their degradation.