Abscisic acid and stress regulate the expression of calmodulin in germinating chick-pea seeds

A full-length cDNA clone for calmodulin has been isolated from a cDNA libra ry constructed from mRNAs of chick-pea seeds germinated for 48 h in H2O, us ing a calmodulin cDNA clone from Fagus sylvatica as a probe. The amino acid sequence of the clone shows high homology ( > 80%) with other plant and an imal calmodulins. The corresponding transcripts, analysed by northern blot, are present during embryogenesis, increase along with seed germination and are repressed by abscisic acid and by several stress conditions (water, sa lt and heat stress) which inhibit chick-pea seed germination. The results o btained suggest that the expression of calmodulin is related to the ability of these seeds to germinate.