Binding of cyclic nucleotides with proteins in malignant and adenosine cyclic 3':5'-monophosphate-induced "differentiated" neuroblastoma cells in culture (original) (raw)
The binding of adenosine cyclic 3':5'-monophosphate (cyclic AMP) with soluble (100,000 X g supernatant), pellet, and total homogenate proteins from cyclic AMP-induced "differentiated" mouse neuroblastoma cells increased by about two-fold. The extent of binding with soluble proteins was higher than that with pellet proteins. The binding of cyclic AMP with soluble proteins from 5'-adenosine monophosphate-treated, serum-free medium-treated, sodium butyrate-treated, 6-thioguanine-treated, or X-irradiated neuroblastoma cells did not significantly change. When the soluble proteins containing bound cyclic [3H]AMP were filtered through a Sephadex G-25 column, the relative amount of protein-bound cyclic [3H]AMP in differentiated cells was greater than that in malignant cells, but the amount of free cyclic [3H]AMP was correspondingly less. The electrophoretic characteristics of cyclic AMP-binding proteins of differentiated and malignant cells were identical. There were t...