FUNCTIONAL-PROPERTIES OF NONMUSCLE TROPOMYOSIN ISOFORMS

Tropomyosins are a family of actin filament binding proteins. They hav e been identified in many organisms, including yeast, nematodes, Droso phila, birds and mammals. In metazoans, different forms of tropomyosin are characteristic of specific cell types. Most non-muscle cells, suc h as fibroblasts, express five to eight isoforms of tropomyosins. The various isoforms exhibit distinct biochemical properties that appear t o be required for specific cellular functions.