MKL/Myocardin Like Protein 1 (MKL1)

MKL1 interacts with the transcription factor myocardin, a key regulator of smooth muscle cell differentiation. The encoded protein is predominantly nuclear and may help transduce signals from the cytoskeleton to the nucleus. This gene is involved in a specific translocation event that creates a fusion of this gene and the RNA-binding motif protein-15 gene.

The protein contains an N-terminal domain, followed by a basic region, a glutamine-rich region, a SAP domain, and a coiled-coil region. Epitope-tagged MKL1 was expressed as a nuclear protein of about 160 kD.Deletion of the first 250 amino acids of MKL1, including the N-terminal domain and the basic region, abolished its transcriptional activity and caused a relocalization of the protein from the nucleus to the cytoplasm.