R&D Systems offers products related to the study of circadian rhythms, which include Clock, CRY1 and PER1.
Clock is a basic helix-loop-helix-PAS transcription factor that heterodimerizes with BMAL1. Together these transcription factors bind to E box elements (CACGTG) within the promoter of Period circadian genes (PER1 and PER2) stimulating their transcription. CRY1 is a critical component of the circadian oscillator that represses CLOCK-BMAL1 mediated transcription when translocated into the nucleus. PER1, also known as RIGUI, influences circadian rhythms by interacting with, and stabilizing, other circadian regulatory proteins.