MYO9B Antibody – Rabbit

This gene encodes a member of the myosin family of actin-based molecular motor heavy chain proteins. The protein represents an unconventional myosin; it should not be confused with the conventional non-muscle myosin-9 (MYH9). The protein has four IQ motifs located in the neck domain that bind calmodulin, which serves as a light chain. The protein complex has a single-headed structure and exhibits processive movement on actin filaments toward the minus-end. The protein also has rho-GTPase activity. Polymorphisms in this gene are associated with celiac disease and ulcerative colitis susceptibility. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

MYO9B: Myosins are actin-based motor molecules with ATPase activity. Unconventional myosins serve in intracellular movements. May be involved in the remodeling of the actin cytoskeleton. Binds actin with high affinity both in the absence and presence of ATP and its mechanochemical activity is inhibited by calcium ions. Also acts as a GTPase activating protein on Rho. Genetic variation in MYO9B is the cause of susceptibility to celiac disease type 4 (CELIAC4). It is a multifactorial disorder of the small intestine that is influenced by both environmental and genetic factors. It is characterized by malabsorption resulting from inflammatory injury to the mucosa of the small intestine after the ingestion of wheat gluten or related rye and barley proteins. In its classic form, celiac disease is characterized in children by malabsorption and failure to thrive. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: Motility/polarity/chemotaxis; GAPs, Rac/Rho; Actin-binding; GAPs; Motor

Chromosomal Location of Human Ortholog: 19p13.1

Cellular Component: ruffle; filamentous actin; filopodium tip; membrane; lamellipodium; perinuclear region of cytoplasm; cytoplasm; cell cortex; cytosol; myosin complex; actin cytoskeleton

Molecular Function: microfilament motor activity; calmodulin binding; actin filament binding; ATP-dependent protein binding; protein binding; protein homodimerization activity; zinc ion binding; ATPase activity; actin-dependent ATPase activity; ADP binding; actin binding; ATP binding

Biological Process: monocyte chemotaxis; regulation of small GTPase mediated signal transduction; ARF protein signal transduction; actin filament-based movement; establishment of cell polarity; metabolic process; small GTPase mediated signal transduction; macrophage chemotaxis

Disease: Celiac Disease, Susceptibility To, 4