Glycoprotein 130 regulates bone turnover and bone size by distinct downstream signaling pathways

Abstract

The gp130-dependent cytokines, which signal through at least two intracellular pathways, regulate osteoclast and osteoblast formation. To define their roles in regulating bone mass, we analyzed mice in which gp130 signaling via either the signal transducer and activator of transcription (STAT) 1/3 (gp130ΔSTAT/ΔSTAT) or SHP2/ras/MAPK (gp130 Y757F/Y757F) pathway was attenuated. In gp130ΔSTAT/Δ STAT mice, trabecular bone volume (BV/TV) and turnover were normal, but bone length was reduced by premature growth plate closure, indicating an essential role for gp130-STAT1/3 signaling in chondrocyte differentiation. In contrast, while bone size was normal in gp130Y757F/Y757F mice, BV/TV was reduced d..