Abstract: An AG to GC switch at nucleotide positions 3064-3065 encoding the wild type NG2　proteoglycan was made by sequential PCR reactions using overlapping primers, res ulting in the change of serine to alanine at amino acid position 999 in the NG2 core protein. Expression constructs pcDNA3.1+/NG2 and pcDNA3.1+/NG2/S999A were made. Transfection of wild-type and mutant forms of NG2 and expression vector pcNA3.1+in U251 cell were performed with LipofectAmine. The NG2 transfectants were isolated, identified by Western Blot. The NG2/S999A transfected U251 cells lack the chondroitin sulfate glycosaminoglycan (CS-GAG) chain. Cell migration assays were performed with these three U251 transfectants. The result suggests that NG2 plays a role in promoting the cell migration. Furthermore, it indicates that the CS-GAG of NG2 could modulate this process.

Key words: NG2 proteglycan, chondroitin sulfate glycosaminoglycan, U251 cells, cell migration