|Qin, Min - USDA/UCB PGEC|
|Kuhn, R - USDA/UCB PGEC|
|Moran, S - USDA/UCB PGEC|
|Quail, Peter - USDA/UCB PGEC|
Submitted to: Plant Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 1, 1997
Publication Date: November 1, 1997
Citation: Qin, M., Kuhn, R., Moran, S., Quail, P.H. 1997. Overexpressed phytochrome C has similar photosensory specificity to phytochrome B but a distinctive capacity to enhance primary leaf expansion. Plant Journal 12(5):1163-1172. Interpretive Summary: Phytochrome C (phyC) is a low-abundance member of the five-membered phytochrome family of photoreceptors in Arabidopsis. Experimental data indicate that phyC may have some physiological roles that are different to those of phyA and phyB in the control of seedling responses to light signals.
Technical Abstract: Phytochrome C (phyC) is a low-abundance member of the five-membered phytochrome family of photoreceptors in Arabidopsis. Towards developing an understanding of the photosensory and physiological functions of phyC, transgenic Arabidopsis plants were generated that overexpress cDNA-encoded phyC and seedling responses to continuous white, red, or farred light (Wc, Rc or FRc, respectively) were examined. Transgenic seedlings overexpressing phyC displayed enhanced inhibition of hypocotyl elongation in Rc, but were unchanged in responsiveness to FRc relative to wildtype. These data indicate that phyC has photosensory specificity that is similar to that of phyB and thus distinct from that of phyA. phyC overexpressors with levels only 3 to 4 times the level of endogenous phyC exhibited enhanced primary leaf expansion in Wc. This is in contrast to phyA or phyB overexpressors which respectively have levels that are 500- and 100-fold that of overexpressed phyC but showed no enhancement of primary leaf expansion. Therefore, phyC may have some physiological roles that are different to those of phyA and phyB in the control of seedling responses to light signals.