Anti-Ca2+, Mg2+-dependent endonuclease antibody detects specifically a class of chromatin-bound endonuclease

A polyclonal antibody against purified bull seminal plasma Ca2+, Mg2+-dependent endonuclease was raised in a rabbit. The antibody specifically cross-reacted with chromatin-bound Ca2+, Mg2+-dependent endonucleases from bovine thymus, human placenta, and bovine, rat and mouse liver in addition to the bovine seminal enzyme. The antibody did not cross-react with other endonucleases examined, including the acid-endonucleases from bovine thymus and liver, porcine spleen DNase II, micrococcal nuclease, and bovine pancreas DNase I, a known Ca2+ and Mg2+ requiring endonuclease. The present results indicate that this antibody specifically recognizes a class of so-called Ca2+, Mg2+-dependent endonuclease, which is localized in cell nuclei of various tissues and is probably involved in chromatin degradation during apoptosis. The antibody will be used to study the functional role of this class of endonuclease.