title: Phytochrome control of electrical potentials and intercellular coupling in oat-coleoptile tissue.
abstract: Microelectrodes were used to demonstrate two electrical responses which occur in oat (Avena sativa L.) coleoptile parenchyma-cells during exposure to red light. The membrane potential of these cells depolarized 5-10 mV in several seconds in red light and repolarized more slowly in far-red light. By pulsing current through the cells, it was found that cellular coupling along the longitudinal axis of the coleoptile increased about 2-fold in red light, but that coupling along the lateral axis was not affected. The rapid changes in membrane potential are consistent with the idea of a membrane locale for early phytochrome action. The coupling experiments suggest that phytochrome may also affect plasmodesmata in this system.
authors.affiliation: Department of Biology, Yale University, 06520, New Haven, CT, USA.
authors.forename: R H
authors.initials: RH
authors.lastname: Racusen