Blue Light Response

Sci. Signal.  09 Dec 2008:
Vol. 1, Issue 49, pp. ec426
DOI: 10.1126/scisignal.149ec426

Plants respond to light with a variety of developmental and physiological changes. The receptor for the blue-light wavelengths is cryptochrome. How blue light causes cryptochrome to alter cellular function has been a puzzle. Now, using a yeast two-hybrid screen, Liu et al. have identified a protein from Arabidopsis, CIB1, which, in the presence of blue light, interacts with cryptochrome. CIB1 and cryptochrome colocalize in the plant cell nucleus, where CIB1 functions as a transcription factor. Together, these proteins bring the input of blue light into the signaling pathways that regulate flowering.

H. Liu, X. Yu, K. Li, J. Klejnot, H. Yang, D. Lisiero, C. Lin, Photoexcited CRY2 interacts with CIB1 to regulate transcription and floral initiation in Arabidopsis. Science 322, 1535–1539 (2008). [Abstract] [Full Text]