The light-induced reduction of the gravitropic growth-orientation of seedlings of Arabidopsis thaliana (L.) Heynh. is a photomorphogenic response mediated synergistically by the far-red-absorbing forms of phytochromes A and B

摘要: Hypocotyls of dark-grown seedlings Arabidosis thaliana exhibit a strong negative gravitropism, which is reduced by red and also long-wavelength, far-red light treatments. Light treatments using phytochrome A (phyA)- B (phyB)-deficient mutants showed that this response controlled phyB in red/far-red reversible way, phyA non-reversible, very-low-fluence response. Crosses the previously analyzed phyB-1 allele (in ecotype Landsberg erecta background) to Nossen wild-type (WT) background resulted WT-like gravitropism darkness, indicating described gravitropic randomization observed with dark likely due second mutation independent PHYB gene.