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.

[EX Q]:  We conclude that peritoneal fluid of endometriosis patients contains activators of PPAR - alpha that stimulate macrophage chemotaxis .
[EX A]: PPAR - alpha

[EX Q]:  Recent studies have increasingly implicated the proteasome in the regulation of cell surface receptors .
[EX A]: cell surface receptors

[EX Q]:  To study the presence of estrogen - binding sites ( EBS ) in the synovial tissues of male and female patients with rheumatoid arthritis ( RA ) and in age - and sex - matched healthy controls .
[EX A]:
binding sites