Evidence for Endoreduplication: Germ Cell DNA Levels Prior to Chromatin Diminution in Mesocyclops edaxEllen M. Rascha and Grace A. Wyngaardba Department of Anatomy and Cell Biology, East Tennessee State University, Johnson City, Tennessee b Department of Biology, James Madison University, Harrisonburg, Virginia Correspondence to: Ellen M. Rasch, Dept. of Anatomy and Cell Biology, J.H. Quillen College of Medicine, Johnson City, TN 37604. E-mail: emrasch@worldnet.att.net We studied the functional significance of marked differences in the DNA content of somatic cells and germ line nuclei by static FeulgenDNA cytophotometry for several species of microcrustaceans that exhibit chromatin diminution during very early stages of embryogenesis. Mature females and males showed many gonadal nuclei with elevated amounts of DNA that persist until dispersal of this "extra" DNA throughout the cytoplasm as fragments and coalescing droplets of chromatin during anaphase of the diminution division. (J Histochem Cytochem 49:795796, 2001) Key Words: somatic cells, germ line nuclei, DNA, microcrustaceans
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