Cytogenetic and protein quantification in polyploid somatic tissue of Myrmeleon uniformis (Neuroptera, Myrmeleontidae)
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Myrmeleon unifomis Malpighian tubules cells were analyzed under two aspects: chro-matin structure and total protein quantifcation in the three larval phases (L<inf>1</inf>, L<inf>2</inf> and L<inf>3</inf>) and in adults. This insect Malpighian tubules present polyploid tissue resultant from endoreduplica-tion, which probably begins in the frst larval phases. The Malpighian tubule proximal region in L<inf>2</inf>, L<inf>3</inf> and adult cells has polyploid nuclei, although the polyploid degree does not cause change in its morphology; nevertheless in the L<inf>3</inf> larvae distal region, polyploidization changes the cell morphology from a round to a multilobulate shape. Chromatin analysis in these nuclei by cytochemical techniques showed that the whole nucleus is flled out with a granular chro-matin. In multilobulate nuclei during L<inf>3</inf> the chromatin is formed by a network of chromatin fbers. The nucleolar markings made in the several development phases of Myrmeleon sp showed the gradual increase that occurs during the larval phases and their reduction in the adult phase. This transcriptional activity was confrmed by total protein analyses, which were quantifed by SDS-PAGE. The 39.8-kDa band deserves prominence, because it can be seen from L<inf>2</inf> phase, increasing its intensity during L<inf>3</inf> and decreasing in the adult phase, indicating that this protein is related to production of the pupation cocoon.