TMEM16A is a major component of Ca(2+)-activated Cl(-) channel (CaCC) conductance in murine portal vein smooth muscle cells (mPVSMCs). Here, the regulation of CaCC activity by the actin cytoskeleton was examined in mPVSMCs. Actin disruption by cytochalasin D did not affect the current density, but increased the deactivation time constant in mPVSMCs. The elongated deactivation was recovered by j...

In previous investigations, we have shown that aggregates of normal human fibroblasts displayed a remarkable number of morphogenetic properties in suspension and on a substratum. The present investigation has attempted to illustrate more clearly the role of colchicine- and cytochalasin-sensitive structures in the observed ultrastructural properties of the fibroblasts in this system. Cytochalasi...

Extraction of SC-1 cells (African green monkey kidney) with the detergent Triton X-100 in combination with stereo high-voltage electron microscopy of whole mount preparations has been used as an approach to determine the mode of action of cytochalasin D on cells. The cytoskeleton of extracted BSC-1 cells consists of substrate-associated filament bundles (stress fibers) and a highly cross-linked...

The motile tips of elongating axons consist of growth cones from which microspikes protrude. Cytochalasin B causes retraction of microspikes, rounding-up of growth cones, and cessation of axon elongation. Drug withdrawal is followed by resumption of growth cone and microspike activity and of axon elongation. In contrast, colchicine causes shortening and retraction of axons, but it does not init...

Human tumor cell lines derived from melanoma, glioblastoma, and carcinoma of the prostate, bladder, and kidney multinucleated in response to growth in cytochalasin B-supplemented medium, whereas cell lines derived from normal prostate, kidney, skin, lung, and other nonmalignant diseases remained predominantly binucleate under comparable conditions. The multinucleate cytochalasin B phenotype was...

In mammals, memory formation and stabilization requires polymerization of actin. Here, we show that, in the honeybee, inhibition of actin polymerization within the brain centres involved in memory formation, the mushroom bodies (MBs), enhances associative olfactory memory. Local application of inhibitors of actin polymerization (Cytochalasin D or Latrunculin A) to the MBs 1 h before induction o...

The redistribution of melanin granules within dermal and epidermal melanocytes of the frog is responsible for changes in skin color . Surviving frog skin can be lightened and darkened by many different compounds (I). When the granules are dispersed into the branched processes of individual melanocytes, the skin appears dark . When melanin granules are aggregated in the perikaryon, the melanocyt...