Ion-channel fragment directs transcription

Voltage-regulated calcium channels such as Ca_V1.2 alter the properties of neurons and muscle cells by controlling the movement of calcium ions into the cells in response to electrical signals. Stanford University neurobiologist Ricardo E. Dolmetsch and his colleagues have now found that these cells also produce a fragment of Ca_V1.2 that travels to the cell nucleus and regulates the transcription of genes into RNA (Cell 2006, 127, 591). The researchers learned that the fragment, which they call calcium-channel-associated transcription regulator, controls the expression of a wide variety of genes involved in activities such as neuronal signaling and growth. "This is the first example of a calcium channel having a dual function as an ion pore and a transcription factor," they point out. The team suggests that fragments of other calcium channels might serve as transcriptional regulators to link the electrical activity of cells to the regulation of genes in the nucleus.