Leaf movement, controlling

Heterocycles controlling leaf movement of plants 99YGK571. 

Potassium channels can have a frequency of one or more channels per square micrometer of membrane surface area. Cellular control can be exerted on the opening of such K+ channels, because concentrations of cytosolic Ca2+ above 3 x 10-4 mol m-3 (0.3 p,M) can inhibit channel opening. Other ion channels in plant membranes are specific for Ca2+ or Cl-. Besides being sensitive to the electrical potential difference across a membrane, some channels apparently open upon stretching of a membrane. Also, many plant cells are excitable and can transmit action potentials, a process in which ion channels are undoubtedly involved. For example, action potentials have been measured for plants responsive to tactile stimuli, such as rapid leaf movements in Mimosa pudica and insectivorous plants (Dionaea spp., Drosera spp.), as well as along the phloem for many species. In addition, ion channels are involved in the long-term maintenance of specific ion concentrations in plant cells. 

Ueda M, Nakamura Y (2010) Plant phenolic compounds controlling leaf-movement. In Santos-Buelga C, Escribano-Bailon MT, Lattanzio V (eds) Recent advances in polyphenol research, vol II. Wiley-Blackwell, Oxford, UK, pp 226-237 Lee DW, Gould KS (2002) Why leaves turn red. Am Sci 90 524-531 Gould KS (2004) Nature s Swiss army knife the diverse protective roles of anthocyanins in leaves. J Biomed Biotech 5 314-320... 

Plant Phenolic Compounds Controlling Leaf Movement... 

Nakamura, Y, Miyatake, R. Ueda, M. (2008). Enantiodifferential approach for the detection of the target membrane protein of the jasmonate glycoside that controls the leaf movement of Albizzia saman. Angewandte Chemie International Edition, 47,7289-7292. 

Ohniiki, T., Ueda, M. Yamamura, S. (1998). Molecular mechanism of the control of nyctinastic leaf-movement in ies/redeza cuneata G. Don. Tetrahedron, 54,12173-12184. 

Ueda, M., OhnuM, T. Yamamura, S. (1997a). The chemical control of leaf-movement in a nyctinastic plant, Lespedeza cuneata G. Don. Tetrahedron Letters, 38,2497 2500. 

Ueda, M., Shigemori, H., Sata, N. Yamamura, S. (2000a). The diversity of chemical substances controlling the nyctinastic leaf-movement in plants. Phytochemistry, 53, 39-44. 

Treatment of Com. Ten microliters of an 80% acetone solution, containing 100 fig. of C14-gibberellin, was applied with a micropipet near the middle of the upper surface of the first leaf, followed by 10 fjl. of 0.1% Tween 20 and 50% ethyl alcohol in order to increase absorption of the radioactive material. The drop of solution was kept from running down by means of lanolin paste. Four normal and four dwarf com plants were thus treated, while untreated plants were kept as controls. The same number of dwarf plants was treated with 0.05 fic. of C14-5-aminotriazole in order to compare the pattern of translocation of gibberellin with that of a compound whose movement has been studied previously (4). The treated plants and controls were then placed in the growth chamber, and one or two specimens were harvested at the end of 1, 2, and 7 days, freeze-dried, and autoradiographed. 

Volatilization rates of chemicals from surface deposits are directly proportional to their relative vapor pressures. The actual rates of loss, or the proportionality constant relating vapor pressure to volatilization rates, are dependent upon external conditions that affect movement away from the evaporating surface, such as wind speed and air turbulence. Initial volatilization of pesticide deposits from leaf surfaces and grass or litter on the forest floor are examples of this type of volatilization. Factors controlling volatilization rates from plants was discussed by Taylor (1). 

The characteristics of the phloem loading system can be summarized as follows. Sucrose loading is (1) dependent on metabolism (2) carrier-mediated (3) selective for sucrose (4) maintains a high concentration inside the phloem which is the basis for the osmotically-driven mass flow of solutions and (5) dependent on the factors which control assimilate supply to the loading sites (e.g., photosynthesis, sucrose synthesis, and sucrose movement between leaf cells, and within subcellular compartments such as the cytoplasm and vacuole) ((>, 7 ). 

Three to four days after the application of C-macu1osin to an unwounded leaf surface there is little or no movement of radioactivity from the inoculation site. Even in a previously wounded leaf, there is only slight movement of labelled material from the point of application. However, there was uptake of radiolabel by knapweed roots suspended in a solution of maculosin. These initial studies have provided useful leads for the practical application of maculosin as a knapweed control agent derivatization of the compound may be necessary for entry and distribution of maculosin in the plant. 

Osmosis contributes to the movement of water through plants. Solute concentrations increase going from soU to root cells to leaf cells, and the resulting differences of osmotic pressure help to draw water upward. Osmosis also controls the evaporation of water from leaves by regulating the size of the openings (stomata) in the leaves surfaces. 

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