Figure 5. Gel filtration analysis of GAG chain length of cell-assciated PGs.

Cell lysate samples eluted from Sephadex G50-fine columns were subjected to alkaline treatment (see Materials and methods) to detach GAG chains from their protein cores. The samples were added the Vo and Vt markers Blue Dextran and K₂CrO₄, respectively, for V_e and K_av calculations, and then applied to Sepharose CL-6B columns to compare the chain lengths of GAGs synthesized by HEK293T cells and COG subunit deficient cell lines. Panel A shows two examples (HEK293T control and COG5) runs. The panels show the size distribution of GAG chains in at least three samples for each cell line. The fractionation range of Sepharose CL-6B being 10,000 to 1,000,000 (for dextrans). 0-0.2 are the longer chains, 0.2-0.8 are intermediate chains. In the V_t, are very short chains with full access to all of the column material, of less than (approximately) 20 disaccharides.