Figure 3.

Blos1-null alleles possess normal-sized synaptic vesicles and presynapse ultrastructure. A, Adult head homogenates were differentially centrifuged and high-speed supernatants resolved by glycerol velocity sedimentation. Synaptic vesicles in fractions were detected by csp immunoblotting (IB). Csp-positive vesicles peaked at the same fractions regardless of the BLOC-1 genotype. B, Representative transmission electron micrographs of larval wild-type (W1118) and Blos1-null (Blos1^ex2) NMJs. Inserts correspond to threefold magnification of areas boxed. C, D, F, Dot plots of synaptic vesicle density, diameter, and the number of T-bars per presynapse, respectively. E, frequency plot of synaptic vesicle diameters. No differences were detected among genotypes. All comparisons were made with Wilcoxon–Mann–Whitney test. NS indicates nonsignificant p values. Dot plots depict number of animals analyzed. Black represents wild-type and blue symbols Blos1-null animals, respectively.