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.

 Biochemical studies have identified a cellular non - P element - encoded DNA binding protein , termed the inverted repeat binding protein ( IRBP ) , that specifically interacts with the outer half of the 31 - bp terminal inverted repeats .

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
P element