Fig. 7

Reciprocal regulation of GPR55 expression and RANKL-induced osteoclastogenesis of RAW264.7 macrophages. a Time-course of Gpr55 mRNA levels in precursor RAW264.7 cells in absence (w/o) or presence of 30 ng/mL RANKL. Transcripts were quantified by real-time PCR and normalised using β₂-microglobulin expression, as the housekeeping gene. Data are means ± SEM from three independent experiments. b–f Real-time PCR analysis of osteoclastogenesis markers (as indicated) in RAW264.7 cells interfered with non-targeting (si-NT) or Gpr55-targeting (si-GPR55) siRNAs, and subsequently treated without (w/o) or with 15–30 ng/mL RANKL for 72 h. The transcripts were quantified and normalised using β₂-microglobulin expression, as the housekeeping gene. Data are means ± SEM from four independent experiments. *p < 0.05; **p < 0.01 (Student’s t-tests). w/o, cells incubated without RANKL; RANKL, RANKL-differentiated cells