Heavy meromyosin treatment forms characteristic arrowhead complexes with actin filaments in a variety of cell types not usually thought to contain actin filaments.
The study demonstrates that actin filaments are present and can form arrowhead complexes with heavy meromyosin in a variety of non-muscle cell types.
Heavy meromyosin (HMM) forms characteristic arrowhead complexes with actin filaments in situ. These complexes are readily visualized in sectioned muscle. Following HMM treatment similar complexes appear in sectioned fibroblasts, chondrogenic cells, nerve cells, and several types of epithelial cells. Thin filaments freshly isolated from chondrogenic cells also bind HMM and form arrowhead structures in negatively stained preparations. HMM-filament complexes are prominent in the cortex of a variety of normal metaphase and Colcemid-arrested metaphase cells. There is no detectable binding of HMM with other cellular components such as microtubules, 100-A filaments, tonofilaments, membranes, nuclei, or collagen fibrils. The significance of HMM-filament binding is discussed in view of the finding that arrowhead complexes form in types of cells not usually thought to contain actin filaments.
Ishikawa et al. (1969) studied Cellular actin filament visualization. Heavy meromyosin (HMM) treatment was evaluated on Formation of arrowhead complexes. Heavy meromyosin treatment forms characteristic arrowhead complexes with actin filaments in a variety of cell types not usually thought to contain actin filaments.