| Abstract: | DNAase I, an endonuclease which interacts with G-actin, also affects tropomyosin polymerization. With chicken pectoralis or bovine cardiac ventricle tropomyosin, DNAase I both prevents tropomyosin from polymerizing and disrupts already formed tropomysin filaments. DNAase I and filament tropomyosin can also form a precipitable complex. In the electron microscope, the complex is observed as irregularly margined stellate-shaped structures with a maximum size of 9 micron. Isolated DNAase I-tropomyosin stellate complex consists of a 2:1 molar ratio of DNAase I and tropomyosin, suggesting that each tropomyosin subunit can bind DNAase I. |
