CHANGES IN CONTENT OF CALMODULIN IN IAA-AND 6-BA-INDUCED SWELLING OF PROTOPLASTS FROM HYPOCOTYL IN ETIOLATED MUNG BEAN SEEDLINGS

Abstract:

Calmodulin (CaM) content in protoplasts cultured with CaCl₂-or IAA (or 6-BA)-bearing medium raised after being incubated for 30 minutes. When treated with IAA (or6-BA)+CaCl₂, the CaM content decreased sharply, which just coincided with the increase of ⁴⁵Ca²⁺ accumulation and protoplast swelling as indicated in our previous studies. Eitherverapadril, LaCl₃, EGTA or W7 could increase the low CaM content to an approximate oreven higher value than that of control. A23187 and cations such as K⁺ and Zn²⁺,however, could reduce CaM level just as the influences of IAA or 6-BA with Ca²⁺, It was also consistent with the changes of ⁴⁵Ca²⁺ accumulation and protoplast volume．These results showed that CaM did act with Ca²⁺ during the modulation of protoplast swelling induced by IAA or 6-BA．