• 1 Synthetic Genomics Research Group, Biomass Engineering Research Division, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan
  • 2 Bio-Active Compounds Discovery Research Unit, RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
  • 3 Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
  • 4 Department of Botany and Plant Sciences, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, CA, USA
  • 5 Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
Plant Cell Physiol, 2017 01 01;58(1):95-105.
PMID: 28011868 DOI: 10.1093/pcp/pcw181


Plants have a remarkable ability to perceive and respond to various wavelengths of light and initiate regulation of different cascades of light signaling and molecular components. While the perception of red light and the mechanisms of its signaling involving phytochromes are largely known, knowledge of the mechanisms of blue light signaling is still limited. Chemical genetics involves the use of diverse small active or synthetic molecules to evaluate biological processes. By combining chemicals and analyzing the effects they have on plant morphology, we identified a chemical, 3-bromo-7-nitroindazole (3B7N), that promotes hypocotyl elongation of wild-type Arabidopsis only under continuous blue light. Further evaluation with loss-of-function mutants confirmed that 3B7N inhibits photomorphogenesis through cryptochrome-mediated light signaling. Microarray analysis demonstrated that the effect of 3B7N treatment on gene expression in cry1cry2 is considerably smaller than that in the wild type, indicating that 3B7N specifically interrupts cryptochrome function in the control of seedling development in a light-dependent manner. We demonstrated that 3B7N directly binds to CRY1 protein using an in vitro binding assay. These results suggest that 3B7N is a novel chemical that directly inhibits plant cryptochrome function by physical binding. The application of 3B7N can be used on other plants to study further the blue light mechanism and the genetic control of cryptochromes in the growth and development of plant species.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.