Fig. 4.

LT induces glucosylation of GTPases inAplysia. A, Immunochemical detection of small GTPases present in Aplysia nerve tissue. Total protein homogenates (20 μg) were subjected to gel electrophoresis and transferred to nitrocellulose sheets, and the GTPases were detected using anti-Rho, anti-Rac1, anti-Cdc42, anti-Ras, anti-Ral, and anti-Rap antibodies. B, Samples of Aplysia nerve tissue fractions (S, soluble; I, insoluble) containing 100 μg of neuronal proteins were incubated with LT82 or LT9048 (5 μg/ml each) and UDP-¹⁴C-glucose alone (denoted as −) or in the presence of 10 mm UDP-mannose (denoted as +), submitted to SDS-PAGE, and autoradiographed. The position of molecular weight markers is indicated.