Abstract
Expression of genes encoding the light-harvesting chlorophyll a/b binding proteins of photosystem II (Cab) in etiolated wheat seedlings is controlled by phytochrome and a circadian clock. Even photoconversion of <1% of phytochrome to its active form, which can be achieved by moonlight, induces the expression of the Cab genes, particularly that of the Cab-1 gene, in circadian fashion. Thus, this reaction shows the characteristics of a low and a very low fluence response. A single far-red light pulse given to an etiolated seedling is sufficient for a persistence of the circadian oscillation of the Cab-1 mRNA level for at least 100 h. Subsequent red (R) or long-wavelength far-red (RG9) light irradiations alter the free running rhythm. These observations indicate a change in sensitivity to phytochrome and/or a control by stable phytochrome. The latter hypothesis is supported by the observation that the level of Cab-1 mRNA is increased or decreased by a second R or RG9 light pulse, respectively.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
