Purification and subunit structure of bovine brain modulator binding protein.

摘要: A protein which can associate with the Ca”-dependent modulator resulting in inhibition of Ca’+-activatable cyclic nucleotide phosphodiesterase has been discovered recently and designated as binding (Wang, J. H., Desai, R. (1977) Biol. Chem. 252,4175-4183; Klee, C. B., Krinks, M. H. (1978) Biochemistry 17, 120-126). This is purified from bovine brain to near homogeneity. The purification procedure based mainly on Ca’+dependent association this highly acidic protein. shown be a globular molecular weight 85,000. It contains two distinct subunits, subunits B, weights about 60,000 14,500, respectively. mass ratio A/ B determined 2.3 : 1. From these results, subunit structure suggested AB2. In presence 6 M urea, dissociates into its constituent separated G-100 Sephadex column. isolated exhibits inhibitory activity against Ca”-activatable phosphodiesterase. Subunit no inhibiting activity, nor does it affect enzyme reaction. These results suggest that responsible for function not known at present.