The nuclear content isolated from middle and large size oocytes of two species of newts has been incubated in tritiated phenylalanine. The most peculiar structures of lampbrush chromosomes have been observed after autoradiographic technique. Spheres, globules and every kind of loop appear to be labelled; the tracts of chromosome axis which do not bear any loops, and possibly telomeres and centromeres do not incorporate phenylalanine. Carrying on such researches, more extensive work will be done in order to characterize specifically the single morphological landmarks, which allow lampbrush chromosomes to be mapped, also on the basis of their functional meaning.
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Con il contributo del Ministero per i Beni e le Attività Culturali