In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
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Question:  This regulation is mediated by several kinases that phosphorylate specific residues in the different functional domains of the p53 molecule .

Answer: p53 molecule


Question:  Platelet factor 4 levels in patients with coronary artery disease .

Answer: Platelet factor 4


Question:  In contrast , postmitotic neurons possessed extremely low levels of E2F1 protein as assessed by the electrophoretic mobility shift assay and Western blotting .

Answer:
E2F1 protein