Synaptic plasma membrane tubulin may be an integral constituent.

Mild detergent extraction of chick brain synaptic plasma membranes followed by gel electrophoresis suggests that synaptic plasma membrane tubulin is an integral component. Although some of the synaptic plasma membrane tubulin might be aggregates, that possibility is not supported by the observation that tubulin aggregates that are added to synaptosomes before synaptic subfractionation do not partition with synaptic plasma membranes during membrane isolation.