๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Effects of white, blue, red light and darkness on pH of the apoplast in theSamaneapulvinus

โœ Scribed by Youngsook Lee; Ruth L. Satter

Publisher
Springer-Verlag
Year
1989
Tongue
English
Weight
983 KB
Volume
178
Category
Article
ISSN
0032-0935

No coin nor oath required. For personal study only.

โœฆ Synopsis

Leaflet movements in Samanea saman (Jacq.) Merrill are driven by fluxes of K +, anions, and water through membranes of motor cells in the pulvinus (R.L. Satter et al., 1974, J. Gen. Physiol. 64, 413 430). Extensor cells take up K + and swell in white light (WL) while flexor cells take up K + and swell in darkness (D). Excised strips of extensor and flexor motor tissue acidify their bathing medium under conditions that normally promote increase in K + in the intact tissue, and alkalize the medium under conditions that normally induce decrease in K + (A. Iglesias and R.L. Satter, 1983, Plant Physiol. 72, 564). To obtain information on pH changes in the whole pulvinus, we measured effects of light on pH of the apoplast, using liquid membrane microelectrodes sensitive to H +. We report the following: (1) The pH of the extensor apoplast was higher than that of the flexor apoplast in WL and in D (pH gradient of 1.0 units in WL and 2.0 units in D). Apoplastic pH might affect K + transport through the plasma membranes of Samanea motor cells, since the conductance, gating, and selectivity of ionic channels in other systems depend upon external pH. (2) Extensor cells acidified and flexor cells alkalized their environment in response to irradiation with WL, while the reverse changes occurred in response to D. These results are consistent with the results of Iglesias and Satter (1983), and support the physiological relevance of data obtained with excised tissue. (3) The pH changes in response to irradiation with red light were similar to those obtained with D; also, the pH changes in response to blue light were similar to those obtained with WL. The pul-

๐Ÿ“œ SIMILAR VOLUMES

Effects of red and blue light on the com
Effects of red and blue light on the composition and morphology of maize kernels grownin vitro
โœ Frederick C. Felker; Douglas C. Doehlert; Kenneth Eskins ๐Ÿ“‚ Article ๐Ÿ“… 1995 ๐Ÿ› Springer ๐ŸŒ English โš– 452 KB

Growth and development of plants are known to be affected by exposure to red and blue light. Mechanisms by which light quality influences gene expression in maize (Zea mays L.) embryos have not been explored. Maize kernels can be cultured in vitro allowing experimental manipulation of environmental

Effects of light, temperature, pH, and i
Effects of light, temperature, pH, and inhibitors on the ATP level of the blue-green algaAnacystic nidulans
โœ T. Bornefeld; W. Simonis ๐Ÿ“‚ Article ๐Ÿ“… 1974 ๐Ÿ› Springer-Verlag ๐ŸŒ English โš– 517 KB

The dependence of the ATP level of the blue-green alga Anacystis nidulans on light intensity (300-20000 erg. cm -~. s -1 white light) and on temperature (0-50~ pH (6.5-9.0), and phosphate concentration (up to 10 -1 M) in light (20000 lx) and dark was measured. In contrast to a low ATP level in darkn

Long-term effects of blue or red light o
Long-term effects of blue or red light on ATP and ADP contents in primary barley leaves
โœ N. G. Bukhov; V. V. Bondar; I. S. Drozdova ๐Ÿ“‚ Article ๐Ÿ“… 1995 ๐Ÿ› Springer-Verlag ๐ŸŒ English โš– 566 KB

Levels of ATP and ADP were studied in primary leaves of barley (Hordeum vulgare L. cv. Viner) seedlings grown under blue (BL) or red light (RL) of various irradiances. In mature leaf segments, BL stimulated a greater accumulation of adenylates than RL. Transfer of barley seedlings from RL to BL for

Effects of narrow-beam irradiations with
Effects of narrow-beam irradiations with blue and far-red light on the timing of cell division inAdiantumgametophytes
โœ Masamitsu Wada; Masaki Furuya ๐Ÿ“‚ Article ๐Ÿ“… 1978 ๐Ÿ› Springer-Verlag ๐ŸŒ English โš– 650 KB

Protonemata of the fern Adiantum capillusveneris L., grown as single-cell filaments under continuous red light, were irradiated with a narrow beam of blue light. Only irradiation of the region containing the nucleus induced cell division. Beams of 30 ฮผm in width, which corresponds to the diameter of