Alkaline phosphatase from teratocarcinoma F9 cells: Isozyme type and effect of treatment of the cells with retinoic acid and dibutyryl cyclic AMP on the enzyme.

Abstract

Alkaline phosphatase [orthophosphoric monoester phosphohydrolase (alkaline optimum), EC 3. 1. 3. 1.] from the F9 mouse teratocarcinoma stem cell line showed properties similar to those of the enzymes from mouse calvaria, kidney, and submandibular gland with respect to sensitivity to inhibitors like L-homoarginine, L-phenylalanine, and levamisole; but the F9 enzyme was clearly distinguishable from the intestine type. A comparision of the effects of zinc ion and ethylendiamine tetraacetic acid on these enzymes, and of pH optima and heat stabilities of the enzymes, also supported the above result, indicating that the F9 alkaline phosphatase belongs to the liver/bone/kidney type of isozyme. The enzyme activity in F9 cells was transiently increased by short-term treatment of the cells with both retinoic acid and dibutyryl cyclic AMP: the activity reached the maximum level of 2.5-fold over that in the control cells by a 24-hour treatment; then it returned to a level similar to that of the control at 48 hours. Analysis of the enzyme by polyacrylamide gel electrophoresis showed that the F9 enzyme increased by the treatment was identical to that present in the control cells.