Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Published Online November 6, 2008
Science DOI: 10.1126/science.1163927

Reports

Submitted on July 29, 2008
Accepted on October 28, 2008

Photoexcited CRY2 Interacts with CIB1 to Regulate Transcription and Floral Initiation in Arabidopsis

Hongtao Liu 1, Xuhong Yu 1, Kunwu Li 1, John Klejnot 1, Hongyun Yang 1, Dominique Lisiero 1, Chentao Lin 1*

1 Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, CA 90095, USA.

* To whom correspondence should be addressed.
Chentao Lin , E-mail: clin{at}mcdb.ucla.edu

Cryptochromes (CRY) are photolyase-like blue light receptors that mediate light responses in plants and animals. How plant cryptochromes act in response to blue light is not well understood. We report here the identification and characterization of the Arabidopsis CIB1 (cryptochrome-interacting basic-helix-loop-helix) protein. CIB1 interacts with CRY2 (cryptochrome 2) in a blue light–specific manner in yeast and Arabidopsis cells, and it acts together with additional CIB1-related proteins to promote CRY2-dependent floral initiation. CIB1 binds to G box (CACGTG) in vitro with a higher affinity than its interaction with other E-box elements (CANNTG). However, CIB1 stimulates FT messenger RNA expression, and it interacts with chromatin DNA of the FT gene that possesses various E-box elements except G box. We propose that the blue light–dependent interaction of cryptochrome(s) with CIB1 represents an early photoreceptor signaling mechanism in plants.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
REVEILLE1, a Myb-like transcription factor, integrates the circadian clock and auxin pathways.
R. Rawat, J. Schwartz, M. A. Jones, I. Sairanen, Y. Cheng, C. R. Andersson, Y. Zhao, K. Ljung, and S. L. Harmer (2009)
PNAS 106, 16883-16888
   Abstract »    Full Text »    PDF »
Flowering Newsletter bibliography for 2008.
Compiled by, F. Tooke, T. Chiurugwi, and N. Battey (2009)
J. Exp. Bot.
   Full Text »    PDF »
Blue Light Induces Degradation of the Negative Regulator Phytochrome Interacting Factor 1 to Promote Photomorphogenic Development of Arabidopsis Seedlings.
A. Castillon, H. Shen, and E. Huq (2009)
Genetics 182, 161-171
   Abstract »    Full Text »    PDF »
Formation of Nuclear Bodies of Arabidopsis CRY2 in Response to Blue Light Is Associated with Its Blue Light-Dependent Degradation.
X. Yu, R. Sayegh, M. Maymon, K. Warpeha, J. Klejnot, H. Yang, J. Huang, J. Lee, L. Kaufman, and C. Lin (2009)
PLANT CELL 21, 118-130
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)