Action of Cytochalasin D on Cells of Established Lines

Abstract

HeLa, Vero, L, HEp2, and MDBK cells respond immediately to 0.2–0.5 µg/ml cytochalasin D (CD) with sustained contraction (contracture), loss of microvilli, expression of endoplasmic contents (zeiosis), nuclear protrusion, and extension of cytoplasmic processes. The development of these changes is depicted, and the dose-response patterns in these cell lines are described. MDBK is generally most resistant and HeLa most sensitive to these effects of CD. Cells in G1 are most sensitive to CD; responsiveness decreases progressively during early S and is least in mid S through G2. CD inhibits transport of [14C]deoxyglucose in HeLa by about 45% but has no significant effect on hexose uptake in Vero and MDBK; sugar transport is thus apparently unrelated to any morphologic effect of CD. Although spreading and attachment are impeded, CD does not decrease and may even enhance the adhesiveness of established monolayers. Contraction appears to be a primary early effect of CD, upon which other visible changes follow. It is prevented by some inhibitors of energy metabolism (deoxyglucose and dinitrophenol) and does not occur in glycerinated models without ATP. The possible bases of the contractile response to CD are discussed. Although direct or indirect action of CD on some microfilaments may occur, a generalized structural disruption of contractile filaments by CD is considered unlikely.

Ultrastructural and Immunofluorescence Studies of Early Events in Adenovirus-HeLa Cell Interactions

“…2 d). As has been shown in other SEM studies (Miranda et al, 1974), cytochalasin B was found to cause HeLa cells to contract, lose microvilli and develop blunt, knobby projections. Such cells were unable to mediate redistribution of virus particles across their surface (Fig.…”

Actions of cytochalasins on the organization of actin filaments and microtubules in a neuronal growth cone.

“…As a control for possible CB effects caused by alteration of hexose transport, experiments were performed using cytochalasin D (18,31,36). Results similar to those described above were obtained with cytochalasin D; however, recovery from cytochalasin D was a slower process.…”

Cytochalasin D induces increased actin synthesis in HEp-2 cells.

“…One of the effects of cytochalasins on living cells which is not observed with pure actin in vitro is a rearrangement of the actin-containing components of their cytoskeletons into aggregated masses (references 20, 21, 35, and 52, among others; review in reference 18). This rearrangement is dependent on metabolic energy (20,21,34,43) and is accompanied by little or no depolymerization of cellular actin (3, 36). We have previously reported that treatment of HEp-2 cells with cytochalasin D (CD) induced an increase in the relative content of total cellular actin (36).…”