Events in the Phytochrome Molecule After Irradiation

Rüdiger, Wolfhart

doi:10.1111/j.1751-1097.1992.tb02236.x

Cited by 31 publications

(22 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2). This result clearly suggests that a red light and a far-red light-absorbing intermediate are reversibly interconverted upon irradiation as it is the case in the plant photoreceptor phytochrome [8,9].…”

Section: Resultsmentioning

confidence: 71%

A photoreceptor with characteristics of phytochrome triggers sporulation in the true slime mould Physarum polycephalum

Starostzik

Marwan

1995

FEBS Letters

View full text Add to dashboard Cite

Phytochrome is a ubiquitous photoreceptor in plants that controls a variety of responses to light, including gene expression, differential cell growth and intracelhilar movement of organelles. All phytochromes analysed so far are reversibly interconverted by light between an inactive and an active conformation, each of which has a different and characteristic absorbance spectrum. Based on photophysiological measurements we provide evidence, that a photoreceptor with these unique properties of phytochrome triggers sporulation in the true slime mould Physarum polycephalum.

show abstract

Section: Resultsmentioning

confidence: 71%

A photoreceptor with characteristics of phytochrome triggers sporulation in the true slime mould Physarum polycephalum

Starostzik

Marwan

1995

FEBS Letters

View full text Add to dashboard Cite

show abstract

“…The resulting Pfr chromophore is more exposed to the medium than the Pr chromophore (Furuya & Song, 1994;Hahn et al, 1984;Chai et al, 1987;Singh et al, 1989;Vierstra & Quail, 1983). Studies have shown that in Pfr the distance between the N-terminus and the chromophore decreases by 12 Å Parker et al, 1992), and the protein responds with an increase in the N-terminus helicity (Singh et al, 1989;Rüdiger, 1992). The importance of this increase in helicity for the regulation of photomorphogenic processes by Pfr is underscored by the observation that the N-terminus is required for full physiological activity (Cherry et al, 1992;Stockhaus et al, 1992).…”

mentioning

confidence: 96%

Mechanism of Native Oat Phytochrome Photoreversion: A Time-Resolved Absorption Investigation

et al. 1996

View full text Add to dashboard Cite

The regulation of plant photomorphogenesis is mediated by the thermal reactions that follow light absorption by the phytochrome photoreceptor. Phytochromes are tetrapyrrolic chromoproteins that exist in two photochromically interconvertible forms, a red light absorbing species, Pr, and a far-red light absorbing form, Pfr. Upon irradiation with 670 nm light, the inactive, red light sensing Pr form is converted to the active Pfr form. Although the forward phototransformation has been studied extensively by several groups using various techniques, the Pfr-->Pr photoreversion reaction that occurs upon irradiation with 730 nm light is not as thoroughly characterized. In this study, time-resolved absorption (TROD) spectroscopy is used to examine the intermediate species involved in the phytochrome photoreversion mechanism at 10 degrees C. Analysis of the TROD data identifies three species with lifetimes of 320 ns, 265 microseconds, and 5.5 ms. TROD results are described in terms of the simplest parallel and sequential kinetic models. Comparison of intermediate spectra from these mechanisms with those of previously reported species from flash photoreversion and low-temperature studies indicates that Pfr photoreversion follows a sequential pathway that does not share any intermediates with the Pr phototransformation pathway.

show abstract

“…The photochemical interconversion processes of phytochromes have been extensively studied for many years (Butler 1972;Kendrick and Spruit 1977;Rüdiger 1992;Braslavsky et al 1997;Braslavsky 2003). Since Pr and Pfr have overlapping absorption spectra in most regions of the light spectrum, Pr-to-Pfr and Pfr-to-Pr photoconversion processes lead to the formation of a photoequilibium consisting of a mixture of Pr and Pfr forms under saturating illumination.…”

Section: Phytochrome Photointerconversionsmentioning

confidence: 99%