Production of Antibody against Spinach Calmodulin and its Application to Radioimmunoassay for Plant Calmodulin

A rabbit antiserum against spinach calmodulin was prepared and characterized. In Ouchterlony's immunodiffusion test, the antiserum gave with spinach calmodulin rise to a single precipitin line. The antiserum crossreacted with pea, wheat and corn calmodulin with single precipitin lines which completely fused. However, it did not react with bovine brain calmodulin. NAD kinase purified from pea seedlings was inhibited when calmodulin was removed by treatment with the anti-calmodulin serum. A specific radioimmunoassay for plant calmodulin was developed to determine calmodulin content in pea plant tissues. Calmodulin contents were high in growing tissues such as shoot apex and hook in etiolated plants. In green plants, calmodulin content was high in leaf tissues.