MRTF-B Activators

Uridine 5'-triphosphate (UTP), apart from its role in intracellular metabolism as a precursor to RNA, acts extracellularly as a signaling molecule by activating purinergic receptors. These receptors are widely recognized for their role in cellular signaling processes, including the regulation of the actin cytoskeleton. Actin dynamics are critical for numerous cellular functions, from cell motility and division to the maintenance of cell shape and volume.

When UTP engages these purinergic receptors, it can initiate a cascade of intracellular events that lead to the rearrangement of the actin cytoskeleton. This reorganization is key to the function of MRTF-B, a coactivator that, when released from its actin-bound form in the cytoplasm, translocates to the nucleus. Here, MRTF-B interacts with Serum Response Factor (SRF) to stimulate the transcription of genes associated with cytoskeletal organization and muscle cell differentiation. Therefore, by influencing the polymerization state of actin-promoting the formation of more F-actin and less G-actin-UTP can indirectly facilitate the activation of MRTF-B. This activation can lead to increased expression of genes under the control of MRTF-B and SRF, highlighting the indirect role extracellular signals like UTP can play in gene expression regulation.