Fluorescence and photochemical properties of phytochromes A and B in etiolated pea seedlings

A Dominant Mutation in the Pea PHYA Gene Confers Enhanced Responses to Light and Impairs the Light-Dependent Degradation of Phytochrome A

“…Growth and harvest of plant material and spectrophotometric measurements of phytochrome were carried out according to previously described methods (Weller et al, 1995;Sineshchekov et al, 1999).…”

Two modes of the light-induced phytochrome A decline – with and without changes in the proportion of its isoforms (phyA′ and phyA″): evidence from fluorescence investigations of mutant phyA-3D pea

“…The shape of the spectrum of the old light-treated roots was very close to that of the phyAphyB-deficient pea mutant [13]. (c, f) -seedlings grown under far-red light (k a P 720 nm).…”

“…3: Spectrum of 11-day-old wild-type pea root sections at its base after saturating red (633 nm) illumination to convert Pr into the far-red absorbing form (Pfr). Spectrum 3 is very close to the spectrum of etiolated seedlings of the double mutant [13] lacking phyA and phyB (phyAphyB) suggesting that the sample 3 contains almost no phytochrome. The spectrum is taken as a spectrum of background emission for corrections of the experimental spectra 1 and 2 to get real spectra of phytochrome (see Fig.…”

“…The experimental approach was the same as that used earlier (see [11][12][13][14]17,18,21,22] and the literature cited therein). To obtain the phytochrome parameters in the sample, low-temperature (85 K) emission spectra (wavelength of the excitation, k e , 610 or 650 nm) were taken under two different experimental settings (see Figs.…”

“…With the use of in situ low-temperature fluorescence spectroscopy, two phyA native species, phyA 0 and phyA 00 , were found in experiments on phyBdeficient mutants (of cucumber [11], Arabidopsis [12] and pea [13]) and on roots of the wild type tobacco, which according to [6] contains almost no phyB (V. Sineshchekov, unpublished results). The most pronounced phenomenological difference of the two phyA species, which allows their quantitative assay in plant tissues, is high and low extent (c 1 ) of the Pr conversion into the first photoproduct, lumi-R, %0.5 for phyA 0 and %0.05 for phyA 00 (Pr 0 and Pr 00 phenomenological types, respectively).…”