mRNA expression of osteoclast specific genes is suppressed by SH3BP2 knockdown. Relative mRNA expression of osteoclast specific genes in infected Raw264.7 cells after 72 hours of RANKL stimulation was examined by quantitative real time PCR. SH3BP2 knockdown significantly suppressed the expression of TRAP (A), OSCAR (B) and β3 integrin (C) compared with controls. The differences in the expression of Cathepsin K (D) were not significant. (A) 32% of that with empty vector (*p<0.0001) and 34% of that with scramble shRNA (*p<0.05) at 72 hours, (B) *p<0.05 compared with both control vectors at 48 and 72 hours (28% of that with both controls at 72 hours), (C) *p<0.01 compared with empty vector at 48 hours and 42% of that with empty vector (**p<0.005) and 47% of that with scramble shRNA (**p<0.01) at 72 hours, (D) 56% of that with empty vector and 60% of that with scramble shRNA (no significant difference between the empty vector, scramble shRNA and SH3BP2 shRNA).