L-type lectin domain L-type lectin domain In molecular biology the L-like lectin domain is a protein domain found in lectins which are similar to the leguminous plant lectins. Lectins are structurally diverse proteins that bind to specific carbohydrates. This family includes the VIP36 and ERGIC-53 lectins. Although proteins containging this domain were originally identified as a family of animal lectins, there are also yeast representatives. ERGIC-53 is a 53kDa protein, localised to the intermediate region between the endoplasmic reticulum and the Golgi apparatus (ER-Golgi-Intermediate Compartment, ERGIC). It was identified as a calcium-dependent, mannose-specific lectin. Its dysfunction has been associated with combined factors V
Myosin head Myosin head Muscle contraction is caused by the sliding action of thick filaments over thin filaments of the myofibril. Myosin is a major component of thick filaments and most myosin molecules are composed of a head, neck, and tail domain; the myosin head binds to thin filamentous actin, and uses ATP hydrolysis to generate force and "walk" along the thin filament. Myosin exists as a hexamer of two heavy chains, two alkali light chains, and two regulatory light chains. The heavy chain can be subdivided into the globular head at the N-terminal and the coiled-coil rod-like tail at the C-terminal,