Cytoskeleton Proteins

Calponin-1 is a thin filament-associated protein that is implicated in the regulation and modulation of smooth muscle contraction. Calponin-1 is capable of binding to actin, calmodulin, troponin C and tropomyosin. The interaction of calponin-1 with actin inhibits the actomyosin Mg-ATPase activity.

Calretinin is a vitamin D-dependent calcium-binding protein which is abundant in auditory neurons. Calretinin plays a role in diverse cellular functions, including message targeting and intracellular calcium buffering. Calretinin also functions as a modulator of neuronal excitability, and is a diagnostic marker for some human diseases, including Hirschsprung disease and some cancers.

Tubulin is a major cytoskeleton protein that has five distinct forms designated alpha, beta, gamma, delta and epsilon tubulin. The alpha and beta tubulins form a heterodimer that polymerize into the cylindrical microtubule fibers. Both alpha and beta tubulin isomer can be modified by addition of a C-terminal tyrosine residue. This modification may influence polymerization rates. The gamma tubulin isomer is localized to centrosomes which compose the heart of the microtubule organizing center from which microtubule fibers emanate.

Actin, cytoplasmic 1 (beta-actin) is a conserved protein that is involved in various types of cell motility and is ubiquitously expressed in all eukaryotic cells. Defects in beta-actin are a cause of dystonia juvenile-onset (DYTJ). DYTJ is a form of dystonia with juvenile onset. Dystonia is defined by the presence of sustained involuntary muscle contraction, often leading to abnormal postures