This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (30) Citing Articles via Google Scholar Google Scholar Articles by Perdue, D. O. Articles by Leopold, A. C. Search for Related Content PubMed PubMed Citation Articles by Perdue, D. O. Articles by Leopold, A. C. Agricola Articles by Perdue, D. O. Articles by Leopold, A. C.

Environmental and Stress Physiology

Calcium in the Regulation of Gravitropism by Light ¹

Section of Plant Biology, Cornell University, Ithaca, New York 14853, Boyce Thompson Institute, Cornell University, Ithaca, New York 14853

The red light requirement for positive gravitropism in roots of corn (Zea mays cv "Merit") provides an entry for examining the participation of calcium in gravitropism. Applications of calcium chelators inhibit the light response. Calcium channel blockers (verapamil, lanthanum) can also inhibit the light response, and a calcium ionophore, A23187, can substitute for light. One can substitute for red light by treatments which have elsewhere been shown to trigger Ca²⁺ influx into the cytosol, e.g. heat or cold shock. Agents which are known to be agonists of the phosphatidylinositol second messenger system (serotonin, 2,4-dichlorophenoxyacetic acid, deoxycholate) can each partially substitute for the red light, and Li⁺ can inhibit the light effect. These experiments suggest that the induction of positive gravitropism by red light involves a rise in cytoplasmic Ca²⁺ concentration, and that a contribution to this end may be made by the phosphatidylinositol second messenger system.

This article has been cited by other articles:

				E. Cholewa and C. A. Peterson Evidence for Symplastic Involvement in the Radial Movement of Calcium in Onion Roots Plant Physiology, April 1, 2004; 134(4): 1793 - 1802. [Abstract] [Full Text] [PDF]

				H. G. Edelmann, G. Gudi, and F. Kuhnemann The gravitropic setpoint angle of dark-grown rye seedlings and the role of ethylene J. Exp. Bot., July 1, 2002; 53(374): 1627 - 1634. [Abstract] [Full Text] [PDF]