CONTROL OF CILIARY ACTIVITY IN PARAMECIUM .3. EVIDENCE FOR SPECIFIC MEMBRANE-BINDING SITES FOR IONS AND CHOLINERGIC LIGANDS

1. Relative distribution (chemotaxis") of Paramecium aurelia in a T-maze in response to various inorganic salts and nicotinic cholinergic ligands was studied. 2. Several common accumulation responses with a narrow concentration range are shown for ligands with common structural or chemical characteristics indicating specific recognition (receptor) sites (proteins) on the ciliary membrane. 3. "Jamming" experiments demonstrate interactions between some of these sites such that a tentative identity assignment can be made. 4. The chemoaccumulation responses appear to be primarily mediated through a kinesis rather than chemotaxis. © 1979."