Functional Studies of Arabidopsis FIN219 Involvement in Phototropism
Date Issued
2015
Date
2015
Author(s)
Chen, Pei-Yin
Abstract
Environmental factors regulating multiple aspects of plant growth and development. Phototropism is controlled by auxin redistribution. Auxin and jasmonates are plant hormones that play important roles during many phases of the plant life cycle. Auxin and jasmonates use similar mechanisms in signal transduction pathways and they have some crosstalks that have been reported. How plants integrate the external light signal and endogenous Auxin and JA pathways during phototropism remains unknown. FIN219 has been shown to have roles in far-red light and jasmonate signaling and its mutant fin219-2 has a defect under unidirectional blue light. In order to understand the regulatory relationship among FIN219, PHOT, and NRL in MeJA and phototropism signal transduction in Arabidopsis, we examine phenotypic responses, mRNA and protein levels in fin219-2, pGR219, phot1, phot2 and their crossed mutants treated with or without MeJA under unidirectional blue light. Both fin219-2 and pGR219 had defect in phototropism under unidirectional blue light, and MeJA inhibited phototropism. DR5:GFP/fin219-2 had a defect in unidirectional blue light, which didn’t have asymmetric auxins distribution. Not only does FIN219 regulate PHOT1and PHOT2 mRNA levels, but also PHOT1 and PHOT2 redundantly inhibited FIN219. PHOT1 and PHOT2 indirectly participated in phyA-mediated signaling pathway. Our results revealed that FIN219 participates in phot1-mediated signaling pathway in phototropism, and JA signaling may influence phototropic responses in Arabidopsis.
Subjects
phototropism
jasmonate
Type
thesis