Editorial review: Journal of Bone and Mineral Research “CRMP 4 Inhibits Bone Formation by Negatively Regulating BMP and RhoA Signaling”

Collapsin response-mediated protein 4 (CRMP4) regulates the differentiation of mouse bone marrow skeletal stem cells (mBMSCs) into osteoblastic cells. CRMP4 was shown to control the early commitment of murine bone marrow-derived stromal stem cells into the osteogenic lineage. The inhibitory effect of CRMP4 on bone mass revealed its direct involvement in mediating BMP2-induced osteogenesis signaling and a role in osteoblast adhesion and proliferation via regulation of cytoskeletal dynamics in a RhoA-focal adhesion kinase (FAK)-dependent mechanism (1). In this editorial, we discuss the details of Rho and its downstream targets, especially Rho-kinase and CRMP families.