| 英文摘要
| Light and plant hormones play important roles in the regulation of plant growth and development. Cryptochrome 2 (CRY2) is one of the blue light (BL) receptors that mediate de-etiolation primarily under weak blue light and photoperiodic control of flowering in Arabidopsis. Under BL stimulus, CRY2 is quickly ubiquitinated and degraded by CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). FAR-RED INSENSITIVE219 (FIN219) catalyzes the biosynthesis of Jasmonoyl-isoleucine (JA-Ile), a bio-active form of Jasmonic Acid (JA), and is a positive regulator of phytochrome A (phyA) mediated far-red light signaling. Previous studies showed that FIN219 was also involved in CRY2-mediated blue light signaling. The overexpression of FIN219 would resulted in a hypersensitive phenotype in response to blue light, ectopic expression of FIN219 in cry2 mutant did not exhibit obvious phenotype, and overexpression of FIN219 would lead to early flowering phenotype. This study verified the physical interaction between CRY2 and FIN219 protein under blue light, and observed that the CRY2 protein stability decreased with MeJA treatment but increased with the overexpression of FIN219 under blue light. CRY2 and FIN219 functioned together in BL-mediated inhibition of hypocotyl elongation, and CRY2 alleviated the inhibition of hypocotyl elongation caused by MeJA depending on FIN219. In short day (SD) condition, more Flowering Locus T (FT) gene was detected in FIN219 overexpression line. However, more evidence was needed to elucidate the role of FIN219 in CRY2-mediate regulation of flowering. Taken together, FIN219 is involved in CRY2-mediated blue light signaling pathway, and promotes photomorphogenesis in Arabidopsis. |
