Where is smooth muscle actin found?
Alpha-smooth muscle actin, a differentiation marker of smooth muscle cells, is present in microfilamentous bundles of pericytes.
What does smooth muscle actin do?
Alpha-smooth muscle actin (SMA), an actin isoform that contributes to cell-generated mechanical tension, is normally restricted to cells of vascular smooth muscle, but SMA can also be expressed in certain non-muscle cells, most notably myofibroblasts.
What cells express smooth muscle actin?
Alpha-smooth muscle actin is expressed by fibroblastic cells of the ovine anterior cruciate ligament and its free tendon graft during remodeling. J Orthop Res. 2002 Mar;20(2):310-7.
What is alpha SMA a marker for?
α-Smooth muscle actin (α-SMA) is used as a marker for a subset of activated fibrogenic cells, myofibroblasts, which are regarded as important effector cells of tissue fibrogenesis. α-SMA is not a functional marker of fibrogenic cells in skeletal muscle fibrosis associated with muscular dystrophy.
How does smooth muscle contract?
Smooth muscle contraction is caused by the sliding of myosin and actin filaments (a sliding filament mechanism) over each other. Contraction is initiated by a calcium-regulated phosphorylation of myosin, rather than a calcium-activated troponin system.
What does ACTA2 stand for?
ACTA2 (actin alpha 2) is an actin protein with several aliases including alpha-actin, alpha-actin-2, aortic smooth muscle or alpha smooth muscle actin (α-SMA, SMactin, alpha-SM-actin, ASMA). Actins are a family of globular multi-functional proteins that form microfilaments.
What are benign smooth muscle tumors called?
A leiomyoma, also known as fibroids, is a benign smooth muscle tumor that very rarely becomes cancer (0.1%). They can occur in any organ, but the most common forms occur in the uterus, small bowel, and the esophagus.
What is the function of desmin?
Desmin is a myofibrillar protein that is the chief intermediate filament of skeletal and cardiac muscle [40]. It maintains the structural and functional integrity of the myofibrils and functions as a cytoskeletal protein linking Z bands to the plasma membrane.
What are examples of smooth muscle tumors?
Benign smooth muscle tumors include smooth muscle hamartoma and angioleiomyoma. A specific category of leiomyomas are estrogen-receptor positive ones in women. These are similar to uterine leiomyomas and can occur anywhere in the abdomen and abdominal wall.
What are smooth muscle antibodies?
Smooth muscle antibodies (SMA) are autoantibodies, proteins produced by the body’s immune system that recognize and attack its own actin, a protein found in smooth muscle and other tissues, especially the liver. This test detects and measures the amount ( titer) of SMA (or antibody against actin) in the blood.
What causes elevated actin antibodies?
A significant increase in the blood titer of SMA or actin antibody and/or ANA is usually due to autoimmune hepatitis type 1. A small increase in SMA or actin antibody may be present in up to 50% of patients with primary biliary cholangitis ( PBC ).
What is the abbreviation for smooth muscle actin?
How is Smooth Muscle Actin abbreviated? SMA stands for Smooth Muscle Actin. SMA is defined as Smooth Muscle Actin very frequently.
What is an anti smooth muscle?
Anti-smooth muscle antibody is a blood test that detects the presence of antibodies against smooth muscle. The antibody is useful in making a diagnosis of autoimmune hepatitis.