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.

 We conclude from these observations that the cTnC 3 ' Ile element is a composite enhancer that functions through the combined interactions of at least five regulatory elements and their cognate binding factors : three or four E - boxes , a MEF - 2 site , and a MEF - 3 site .
MEF - 2