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.
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Question: The transcriptional events that control T cell tolerance to peripheral self Ags are still unknown .

Answer: peripheral self Ags

Question: 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 .

Answer: nuclear factor

Question: Introduction of Tax into resting Kit 225 cells induced activation of the G1 / S transition regulation cascade consisting of activation of cyclin dependent kinase 2 ( CDK2 ) and CDK4 , phosphorylation of the Rb family proteins and an increase in free E2F .

Answer:
Rb family proteins