Gravicurvature loss, changes in ultrastructure and calcium balance of pea root statocytes treated with EGTA.

Calcium is known to play a key role in the regulation of a wide variety of cellular events in plants, in particular as a second messenger in the transduction of gravity signals in statocytes. In order to investigate the role of extracellular calcium in gravity perception, many investigators have used ethylene glycol-bis-(aminoethyl ether)-N,N'-tetraacetic acid (EGTA), whose main property is the ability to form stable water-soluble complex compounds with divalent metals, particularly with Ca2+ ions, that do not penetrate across plasma membrane into a cell.