Figure 3.

 Deletion of PS loop increases motor binding to membranes. (A) Subcellular fractionation of adult fly brain membranes on sucrose step gradients from WT flies and flies expressing hPSloop show that the levels of active GSK3β, KHC and DIC bound to the membranes (35/8 fraction) are comparable. (B) Quantification analysis indicated that there were no significant changes in the levels of active GSK3β, KHC or DIC in the 35/8 fraction from hPSloop compared with WT (using Student’s t-test). For quantification, the ratio of the intensity of KHC/DIC/active GSK3β for the PNS or the 35/8 fraction was determined against the intensity of Rab5 and normalized to WT from three independent experiments. Y axis depicts the intensity in arbitrary units (AU). Data are presented as mean ± SEM. (C) Subcellular fractionation of adult fly brain membranes from flies expressing PSΔE9 show that the level of active GSK3β and KHC bound to membranes were elevated compared with WT brains. (D) Quantification analysis indicates that the level of membrane bound KHC but not active GSK3β or DIC was significantly increased compared with WT. Statistical analysis using Student’s t-test, Tukey’s HSD test and Bonferroni’s test indicate that only KHC levels were significant. For KHC, **P < 0.005 (P = 0.00425) using Student’s t-test, Tukey’s HSD test (indicated by &&) and Bonferroni’s test (indicated by ##). For active GSK3β, P = 0.05374 and for DIC, P = 0.06909 using Student’s t-test, Tukey’s HSD test and Bonferroni’s test. Y axis depicts the intensity in AU. N = 3 independent experiments. Data are presented as mean ± SEM.