2020 Volume 2 Issue 1 Pages 19-23
C1q/TNF-related protein 3 (CTRP3), a member of the CTRP family, is a soluble protein that is expressed during chondrogenic differentiation and promotes proliferation in chondrogenic cells. However, functional receptor(s) for CTRP3 has not been identified yet. In this study, we reveal progestin and adipoQ receptor family member 2 (PAQR2) [adiponectin receptor 2 (AdipoR2)] as a functional receptor of CTRP3 in chondrogenic cell line (ATDC5). Using RNA interference, we found that PAQR2 inhibition, and not PAQR1, PAQR3, or PAQR4, suppresses CTRP3-induced chondrogenic cell proliferation. In addition, a peptide blocker against PAQR2, and not against PAQR1, was observed to neutralize the growth promoting effect of CTRP3 on chondrogenic cells. Thus, our results suggested that PAQR2 is a functional receptor of CTRP3 in promoting proliferation in chondrogenic cells.