Ref ID : 3722
Janine Dupy-Blanc; Biological Cycle of the Ciliate Enchelys mutans: Cytophotometric Study of the Variations of Macronuclear DNA content. Arch.Protistenk 125:309-321, 1982
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The variations in macronuclear DNA content during the biological cycle of the amicronucleated polymorphic ciliate Enchelys mutans were determined by cytophotometry in the dividing forms and in the nuclei of the small cysts which allow the G1 content of the macronuclei of the piriform types to be estimated. During the cell growth phase of the piriform types, the amount of DNA quadruples, probably by means of two successive replications. If the medium is prey-rich, the trophonts divide actively, maintaining a DNA value twice that of the piriform cells. It is thus probable that there is a return to piriform cells as a result of 2 successive divisions without a phase of DNA synthesis. Anomalies of the cortical structure and of division appear in cultures under conditions of continuous excess of prey (distome, then polystome, forms). In the giant forms the amount of DNA can reach 26 times the Mn content in G1 of the small cysts.