The Presence of Septin Proteins in the Neuromuscular Junction of Somatic Muscle in the Earthworm Lumbricus terrestris

Fluorescent confocal microscopy has shown the presence of the family of septin proteins types 2, 3, 5, 7, and 9 in the somatic muscle of the earthworm Lumbricus terrestris. Septins of types 2 and 9 lack their specific concentration in the cholinergic synapse zone, whereas septins of types 3 and 5, and especially type 7, have a quantitatively expressed binding localization at the zone of the motor end plate. It is assumed that septins of types 3 and 5 and, above all, type 7 may be participants in the mechanisms of modulation of the quantal secretion of the mediator.