Bone morphogenetic protein and retinoic acid signaling cooperate to induce osteoblast differentiation of preadipocytes.

Mesenchymal cells can differentiate into osteoblasts, adipocytes, myoblasts, or chondroblasts. Whether mesenchymal cells that have initiated differentiation along one lineage can transdifferentiate into another is largely unknown. Using 3T3-F442A preadipocytes, we explored whether extracellular signals could redirect their differentiation from adipocyte into osteoblast.

Roles of autocrine TGF-beta receptor and Smad signaling in adipocyte differentiation.

TGF-beta inhibits adipocyte differentiation, yet is expressed by adipocytes. The function of TGF-beta in adipogenesis, and its mechanism of action, is unknown. To address the role of TGF-beta signaling in adipocyte differentiation, we characterized the expression of the TGF-beta receptors, and the Smads which transmit or inhibit TGF-beta signals, during adipogenesis in 3T3-F442A cells.