"myofila" - 1 õppematerjal

Liha töötlemine

attached to the cell membrane (sarcolemma) required for enzymatic activity, and the other by intermediate filaments that interact not has regulatory functions. only with the Z-line, but also with structures Actin is the second-most abundant protein at the sarcolemma known as costameres in the myofibril, accounting for approxi- (Robson et al. 2004). mately 20% of the total protein in the myo- Myofibrils are made up of many myofila- fibril. Actin is a globular protein (G-actin) ments, of which there are two major types, that polymerizes to form filaments (F-actin). classified as thick and thin filaments. There G-actin has a molecular weight of approxi- is also a third filament system composed pri- mately 42,000. There are approximately marily of the protein titin (Wang et al. 1979; 400 actin molecules per thin filament. Thus Wang 1984; Wang et al