Faculty Collaboration Database

Actin cytoskeleton disassembly affects conductive properties of stretch-activated cation channels in leukaemia cells. Biochim Biophys Acta 2005 May 15;1669(1):53-60

Date

04/22/2005

Pubmed ID

15842999

DOI

10.1016/j.bbamem.2005.02.013

Scopus ID

2-s2.0-17444410044 (requires institutional sign-in at Scopus site)   29 Citations

Abstract

Mechanosensitive channels in various eucaryotic cells are thought to be functionally and structurally coupled to the cortical cytoskeleton. However, the results of electrophysiological studies are rather controversial and the functional impact of cytoskeleton assembly-disassembly on stretch-activated channel properties remains unclear. Here, the possible involvement of cytoskeletal elements in the regulation of stretch-activated Ca2+-permeable channels was studied in human leukaemia K562 cells with the use of agents that selectively modify the actin or tubulin system. F-actin disassembly resulted in a considerable reduction of the amplitude of stretch-activated currents without significant change in channel open probability. The effects of treatments with cytochalasins or latrunculin were principally similar, developed gradually and consisted a strong decrease of single channel conductance. Microtubule disruption did not affect stretch-activated channels. The data presented here are in principal agreement with the general conclusion that mechanosensitive channel functions are largely dependent on the integrity of the cortical actin cytoskeleton. Specifically, changes in conductive properties of the pore may provide an essential mechanism of channel regulation underlying functional modulation of membrane currents. Our results allow one to speculate that microfilament organization may be an important determinant in modulating biophysical characteristics of stretch-activated cation channels in cells of blood origin.

Author List

Staruschenko A, Negulyaev YA, Morachevskaya EA

MESH terms used to index this publication - Major topics in bold

Actins
Bridged Bicyclo Compounds, Heterocyclic
Cytochalasin D
Cytoskeleton
Humans
Ion Channels
K562 Cells
Leukemia
Microtubules
Thiazoles
Thiazolidines