Research Repository

Unanticipated regulatory roles for Arabidopsis phytochromes revealed by null mutant analysis

Hu, W and Franklin, KA and Sharrock, RA and Jones, MA and Harmer, SL and Lagarias, JC (2013) 'Unanticipated regulatory roles for Arabidopsis phytochromes revealed by null mutant analysis.' Proceedings of the National Academy of Sciences of the United States of America, 110 (4). pp. 1542-1547. ISSN 1091-6490

CurrentFormattedVersion_10Dec2012.pdf - Submitted Version

Download (564kB) | Preview


In view of the extensive literature on phytochrome mutants in the Ler accession of Arabidopsis, we sought to secure a phytochrome-null line in the same genetic background for comparative studies. Here we report the isolation and phenotypic characterization of phyABCDE quintuple and phyABDE quadruple mutants in the Ler background. Unlike earlier studies, these lines possess a functional allele of FT permitting measurements of photoperiod-dependent flowering behavior. Comparative studies of both classes of mutants establish that phytochromes are dispensable for completion of the Arabidopsis life cycle under red light, despite the lack of a transcriptomic response, and also indicate that phyC is nonfunctional in the absence of other phytochromes. Phytochrome-less plants can produce chlorophyll for photosynthesis under continuous red light, yet require elevated fluence rates for survival. Unexpectedly, our analyses reveal both light-dependent and -independent roles for phytochromes to regulate the Arabidopsis circadian clock. The rapid transition of these mutants from vegetative to reproductive growth, as well as their insensitivity to photoperiod, establish a dual role for phytochromes to arrest and to promote progression of plant development in response to the prevailing light environment.

Item Type: Article
Uncontrolled Keywords: photomorphogenesis; photoperiodism; light signaling; photoreceptor; shade sensing
Subjects: Q Science > QK Botany
Divisions: Faculty of Science and Health
Faculty of Science and Health > Life Sciences, School of
SWORD Depositor: Elements
Depositing User: Elements
Date Deposited: 04 Feb 2013 13:51
Last Modified: 06 Jan 2022 13:30

Actions (login required)

View Item View Item