ENZ function prevents premature differentiation of mouse neural stem cells. Kinase inhibitor treatment differentiates these cells prematurely. This is prevented if a specific serine-to-aspartate (S to D) mutation is introduced in ENZ. Based on this information, which one of the following statements is INCORRECT?

Correct option is C

Correct Answer
(c) 3
Explanation:
Serine-to-aspartate substitutions are commonly used as phosphomimetic mutations because aspartate carries a negative charge similar to a phosphate group. Asparagine, however, is uncharged and cannot mimic phosphorylation. Therefore, a serine-to-asparagine substitution would not yield the same functional outcome.
Information Booster
· Phosphorylation adds negative charge that changes protein conformation and regulates activity.
· Aspartate and glutamate can partially mimic phosphorylation because of their acidic side chains.
· Neutral amino acids cannot reproduce phosphorylation-dependent signaling effects.
Additional Knowledge
(a) Correct: S→D often mimics the effect of phosphorylation on protein function.
(b) Correct: The serine residue is likely a phosphorylation site regulated by a kinase.
(d) Correct: Glutamic acid, like aspartate, is negatively charged and often behaves similarly in phosphomimetic substitutions.