A conserved MADS-box phosphorylation motif regulates differentiation and mitochondrial function in skeletal, cardiac, and smooth muscle cells.

Exposure to metabolic disease during fetal development alters cellular differentiation and perturbs metabolic homeostasis, but the underlying molecular regulators of this phenomenon in muscle cells are not completely understood. To address this, we undertook a computational approach to identify cooperating partners of the myocyte enhancer factor-2 (MEF2) family of transcription factors, known regulators of muscle differentiation and metabolic function. We demonstrate that MEF2 and the serum response factor (SRF) collaboratively regulate the expression of numerous muscle-specific genes, including microRNA-133a (miR-133a).

Rab GTPase mediated procollagen trafficking in ascorbic acid stimulated osteoblasts.

Despite advances in investigating functional aspects of osteoblast (OB) differentiation, especially studies on how bone proteins are deposited and mineralized, there has been little research on the intracellular trafficking of bone proteins during OB differentiation. Collagen synthesis and secretion is the major function of OBs and is markedly up-regulated upon ascorbic acid (AA) stimulation, significantly more so than in fibroblast cells. Understanding the mechanism by which collagen is mobilized in specialized OB cells is important for both basic cell biology and diseases involving defects in bone protein secretion and deposition.

Classically activated macrophages use stable microtubules for matrix metalloproteinase-9 (MMP-9) secretion.

As major effector cells of the innate immune response, macrophages must adeptly migrate from blood to infected tissues. Endothelial transmigration is accomplished by matrix metalloproteinase (MMP)-induced degradation of basement membrane and extracellular matrix components. The classical activation of macrophages with LPS and IFN-γ causes enhanced microtubule (MT) stabilization and secretion of MMPs.