Abstract
Adiponectin, an adipocyte-derived biologically active molecule, is a ∼30-kDa polypeptide containing an N-terminal signal sequence, variable domain, collagen-like domain, and C-terminal globular domain. Previously we demonstrated that full-length adiponectin up-regulated the expression of genes related to osteoblastic differentiation, although the free globular domain down-regulated them. It was hypothesized that the collagen-like domain may be involved in osteoblastic differentiation, so we investigated the effect of novel synthesized collagen-like peptide on osteoblastic differentiation of murine pro-osteoblastic cells.Microarray analysis showed that the collagen-like peptide up-regulated the genes related to various signaling pathways involved in osteoblastic differentiation. In contrast, the globular domain suppressed the above genes and induced the expression of genes related to cell morphogenesis and neurological system processes. Real-time RT-PCR for osteocalcin clarified the microarray observation. Therefore, the novel synthesized collagen-like peptide had positive action on osteoblastic differentiation.
