ABSTRACT
Intrinsic properties of Characean macroalgae and explicit electrical signaling properties provide a model system for complex investigation of instantaneous effects of neurotransmitters on plant bioelectrical signals in vivo. General characteristics of Characean physiology and electrical signaling properties are discussed, specifically focusing on those representing effects of neurotransmitters acetylcholine, dopamine, gamma-aminobutyric acid, and melatonin on single plant cells. Diverse experimental approaches and real-time electrical measurements on intact cells and cytoplasmic droplets after exposure to neurotransmitters are presented. Membrane potential (MP) alterations and action potential (AP) patterns represent the cell responses. The electrical properties of tonoplast ion channels can be studied using cytoplasmic droplets by patch clamping. Investigation of electrical cell-to-cell communication revealed evidence on the electrical signal transduction through plasmodesmata in Characean macroalgae.
