Blue light–specific elongation compound in plants identified

December 14, 2016

A novel inhibitory compound affecting cryptochrome blue-light information

RIKEN CSRS researchers have successfully isolated a low molecular weight compound that inhibits the effects of cryptochrome blue-light receptors. Researchers clarified that the compound, named 3B7N, suppresses cell elongation by directly binding to the cryptochrome-1 (CRY1) protein.

Cryptochrome proteins are blue-light receptors that inhibit de-etiolation, stomatal opening and closing, flowering time and shade avoidance. Seizing on the fact that blue light suppresses cell growth in seedling cells, researchers searched among 4,000 low-molecular-weight compounds capable of interfering with blue-light suppression, using Arabidopsis to test their hypothesis. They discovered that 3B7N affected only blue-light suppression, leaving red and infrared (far red) light receptors unaffected.

A pulldown assay of 3B7N and proteins revealed that 3B7N binds solely to CRY1, leaving other proteins involved in blue-light signaling (such as the previously reported BIC2 protein that inhibits CRY2 signaling) unaffected. In other words, 3B7N specifically interrupts the cryptochrome function that controls cell elongation in seedlings.

Because cryptochrome controls important agronomic traits such as growth and flowering, these results are expected to contribute to increased yields of crop biomass, etc.

 

Original article
Plant and Cell Physiology doi:10.1093/pcp/pcw181
W.-D. Ong, E. Okubo-Kurihara, Y. Kurihara, S. Shimada, Y. Makita, M. Kawashima, K. Honda, Y. Kondoh, N. Watanabe, H. Osada, S. R Cutler, K. Sudesh, M. Matsui,
"Chemical-Induced Inhibition of Blue Light-Mediated Seedling Development Caused by Disruption of Upstream Signal Transduction Involving Cryptochromes in Arabidopsis thaliana".

Contact
Emiko Kurihara; Postdoctoral Researcher
Minami Matsui; Group Director
Synthetic Genomics Research Group