Regulation of chromatin dynamics by a calcium-dependent nucleoskeleton

The present study shows that growth factors increase inositol 1,4,5-trisphosphate (IP3) in the nucleus, which in turn releases calcium from intranuclear IP3 receptors (ITPRs), which then leads to transient assembly of an actin nucleoskeleton that associates with intranuclear MYH9.

Mass spectrometry suggests that much of the MYH9 cargo consists of components of the gene transcription machinery, while chromatin immunoprecipitation identified a number of specific genes that associate with the myosin in response to stimulation with growth factors. Together, these findings suggest that growth factors initiate gene transcription by transiently assembling an actin nucleoskeleton that works with MYH9 to bring specific genes to the transcription machinery.