Question

A particular type of glucose binding protein binds to glucose with an affinity of 0.43 µM. In other words, 1/K = 0.43 µM, where K is the equilibrium constant for the association of glucose with the protein. If glucose concentration is 1 mM, then approximately what fraction of glucose binding

A. Almost none

B. Almost all

C. About half

D. About 10%

In principle, a eukaryotic cell can regulate gene expression at any step in the pathway from DNA to the active protein, including marking proteins for degradation. The overall pathway can be drawn as:

            DNA –––> pre-mRNA –––> mRNA –––> protein –––> inactive or degraded protein

                    –––––                  –––––             –––––              –––––

On the line under each step, indicate what type of regulation occurs from the following list

A. Translation control

B. Transcription control

C. RNA processing control

D. Protein degradation control

Answer 1

1. When 1/K =0.43 at glucose concentration of 1mM, then almost 50% of glucose binding takes place. Option C is correct.

2. DNA –––> pre-mRNA –––> mRNA –––> protein –––> inactive or degraded protein

B. Transcription control C. RNA processing control        A. Translation control     D. Protein degradation control

The DNA to mRNA is formed through transcription and further protein synthesis occur by translation. The formation of mRNA from DNA includes a premRNA phase which is controlled by transcriptional control. The premRNA to mRNA is regulared by RNA processing control. The protein from mRNA is regulated by translational control and finally protein degradation is also regulated.