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.

[Q]:  Bone resorption is regulated by the immune system , where T - cell expression of RANKL ( receptor activator of nuclear factor ( NF ) - kappaB ligand ) , a member of the tumour - necrosis factor family that is essential for osteoclastogenesis , may contribute to pathological conditions , such as autoimmune arthritis .
[A]: nuclear factor


[Q]:  One element is located in the intron between the variable ( V ) and constant ( C ) regions of both heavy and kappa light - chain genes and acts as a transcriptional enhancer .
[A]: transcriptional enhancer


[Q]:  Here we report that cAMP - induced effects in Th2 cells occur independently of the protein kinase A pathway , which is the major mediator of cAMP - induced signaling events in most cell types .
[A]:
protein kinase A