Abstract
Rat and bovine parotid gland and pancreas contain deoxyribonuclease I (DNAase I) activities in different amounts. The DNAase I activity in tissue homogenates of bovine and rat parotid gland can be inhibited by addition of monomeric actin, as with the enzyme of bovine pancreas. The isolated DNAase I species from bovine and rat parotid gland differ in their molecular weights and also in their affinities for monomeric actin, being lowest for rat parotid DNAase I (5 X 10(6)M(-1). Antibodies raised against rat and bovine parotid and bovine pancreatic DNAase I can be used to study the subcellular localization of DNAase I in these tissues by indirect immunofluorescence. DNAase I was found to be confined solely to the secretory granules of the tissue from which it was isolated.