CRY2 Antibody

CRY2 is a photoreceptor that primarily mediates blue light inhibition of hypocotyl elongation and photoperiodic control of floral initiation. It also regulates other light responses, including circadian rhythms, tropic growth, stomata opening, guard cell development, root development, bacterial and viral pathogen responses, abiotic stress responses, cell cycles, programmed cell death, apical dominance, fruit and ovule development, seed dormancy, and magnetoreception. Photoexcited cryptochromes interact with signaling partner proteins to alter gene expression at both transcriptional and post-translational levels, consequently regulating the corresponding metabolic and developmental programs. CRY2 is a blue-light absorbing flavoprotein that activates reversible flavin photoreduction via an electron transport chain comprising a tryptophan triad (W-321, W-374, and W-397), or via an alternative electron transport involving small metabolites, including NADPH, NADH, and ATP. The half-life of the activated signaling state is approximately 16 minutes.

CRY2 perceives low blue light (LBL) and responds by directly contacting two bHLH transcription factors, PIF4 and PIF5, at chromatin on E-box variant 5'-CA[CT]GTG-3' to promote their activity and stimulate specific gene expression to adapt global physiology (e.g., hypocotyl elongation and hyponastic growth in low blue light). In response to blue light, CRY2 binds to CIB proteins (e.g., BHLH63/CIB1 and BHLH76/CIB5) to activate transcription and floral initiation. It mediates blue light-induced gene expression, floral initiation, and hypocotyl elongation through the interaction with SPA1, which prevents the formation of the SPA1/COP1 complex but stimulates COP1 binding, thus inhibiting COP1-mediated degradation of transcription factors (e.g., CO and HY5). CRY2 promotes flowering time in continuous light (LL).

CRY2 is involved in shortening the circadian clock period, especially at 27 degrees Celsius, in blue light (BL). It is required to maintain clock gene expression rhythms. CRY2 triggers nuclear accumulation of ROS in response to blue light illumination. It is involved in blue light-dependent stomatal opening, transpiration, and inhibition of stem and root growth, probably by regulating abscisic acid (ABA). CRY2 regulates the timing of flowering by promoting the expression of 'FLOWERING LOCUS T' (FT) in vascular bundles. It is negatively regulated by 'FLOWERING LOCUS C' (FLC). CRY2 is a general positive regulator of reversible low light-induced chromatin decompaction. It is involved in triggering chromatin decondensation during floral transition. Together with phototropins, CRY2 is involved in phototropism regulation by various blue light fluence; blue light attenuates phototropism in high fluence rates (100 umol.m-2.s-1) but enhances phototropism in low fluence rates (<1.0 umol.m-2.s-1). The effect of near-null magnetic field on flowering is altered by changes of blue light cycle and intensity in a CRY1/CRY2-dependent manner. CRY2 is involved in the strigolactone signaling that regulates hypocotyl growth in response to blue light.

CRY2 confers resistance to turnip crinkle virus (TCV) by preventing COP1-mediated proteasome-mediated degradation of RPP8/HRT, thus promoting its stability in light. Exposure to darkness or blue-light induces degradation of CRY2, and in turn of RPP8/HRT, resulting in susceptibility to TCV.