Cry2 Protein, Mouse (His, Myc)

Cry2 is a transcriptional repressor that forms a core component of the circadian clock, an internal time-keeping system regulating physiological processes through ~24-hour rhythms in gene expression, metabolism, and behavior. Derived from Latin 'circa' (about) and 'diem' (day), it governs functions like metabolism, sleep, and cardiovascular activity. The clock comprises the central clock in the brain's suprachiasmatic nucleus (SCN) and peripheral clocks in tissues, synchronized by Zeitgebers ('timegivers'), primarily light for the SCN. Cry2, alongside Cry1, participates in the transcription-translation feedback loop (TTFL): CLOCK/NPAS2-BMAL1/2 heterodimers activate E-box-containing clock genes, while PER/CRY proteins inhibit them to generate rhythms. Though functionally redundant with Cry1, Cry2 differentially tunes SCN pace by opposing Cry1's effects and is vital for intercellular rhythm synchrony. It mediates circadian cAMP/gluconeogenesis regulation by blocking glucagon-induced cAMP/CREB1 activation. Beyond clock maintenance, Cry2 modulates glucose/lipid metabolism (e.g., via LEP, ACSL4), represses glucocorticoid receptor NR3C1/GR, and limits skeletal muscle PPARD signaling to restrict exercise capacity (by similar: PubMed:28683290). It also inhibits NR1I2 transcriptional activity (by similar: PubMed:28751364).