Impaired trafficking of Glut3 to cell surfaces in primary HD
neurons. Primary neurons at DIV8 were used for studies. A) Western blot analysis of biotinylated cell surface proteins and corresponding post-nuclear supernatants of WT and HD cortical neurons. Shown is one blot analysis of three experiments. B) Densitometry. Intensities of signals for biotinylated Glut3 (cell surface) and for total Glut3 in post-nuclear supernatants were measured using NIH ImageJ. The ratio of biotinylated Glut3 to total Glut3 was used for calculating the percentage of WT, which was set as 100%. Mean ± SD percentage of WT was graphed (n = 3 experiments, Student’ t -test: * p < 0.05). C) Western blot shows distribution of Glut3 compared to that of NCAM, a protein known to locate mainly on the neuronal cell surface, and to that of actin, which is predominantly intracellular. Shown is one of 3 sets of analysis of Glut3, NCAM and actin distribution in primary WT cortical neurons. All of the aqueous solution eluted from the Streptavidin beads and 30% of unbiotinylated proteins were used for Western blot analysis.