Given the task definition and input, reply with output. 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.

In the case of the pT181 plasmid , inactivation of the initiator RepC protein occurs by the attachment of an oligonucleotide to its active tyrosine residue .
initiator RepC protein