Involvement of phosphoinositides, calmodulin and glyoxalase-I in cell proliferation in callus cultures of Amaranthus paniculatus

Abstract

The effect of lithium and trifluoperazine (TFP) was studied on cell proliferation in callus cultures of Amaranthus paniculatus. TFP (20 μM) and lithium (40 mM) inhibited the callus growth by 50% and 80%, respectively. The inhibition by lithium was reversed by the addition of myoinositol (2.5 mM). Equimolar concentration of NaCl, as that of LiCl, had no significant effect on callus growth. The activity of calmodulin was inhibited by TFP as tested both by in vivo and in vitro experiments. The level of phosphatidylinositol (PI) in calli grown on lithium was lower than the calli grown on the medium containing inositol alone. The activity of the enzyme glyoxalase-I was inhibited by lithium and TFP. The inhibition of the enzyme activity by lithium was reversed by the addition of inositol. Possible involvement of phosphoinositide cycle, calcium and calmodulin in cell proliferation in in vitro cultures is suggested.