Preparation of megabase DNA from adult insects and mammalian spleen for pulsed-field gel electrophoresis

Abstract

While std. techniques for obtaining megabase-size DNA from microorganisms and cells in tissue culture are now available, new methods are needed for handling solid tissues and, in the case of small-sized animals, whole organisms. A simple and rapid method is described for prepg. large DNA mols. from mammalian spleen, whole insects of Drosophila, and Planococcus lilacinus, a mealybug. Briefly the method involves gentle steps for prepg. cell suspensions and handling of these cells within agarose blocks for prepg. the DNA. In mammals like mice, the spleen, rather than the liver, is the organ of choice because, in the latter, endogenous nuclease activity is high.