Systematic reorganization of polytene chromosome architecture during the ontogenesis and phylogenesis of malaria mosquitoes. Structural features of the chromosomal nuclear membrane attachment zone
1991
Stegnii, V.N. | Sharakhova, M.V.
Chromocenter organization was studied in salivary gland chromosomes and the chromosomal nuclear membrane attachment zones were studied in ovary sustentacular cells in malaria mosquitoes. Blocks of dense juxtacentromeric heterochromatin (Hetz type alpha) were found not to form direct links with the nuclear membrane. Links were actually formed by "loose" beta-heterochromatin, and the predominance of highly repeated DNA at attachment zones supported this result. Homologous regions of chromosomes involved in nuclear membrane attachment in ovary sustentacular cells differ morphologically in different mosquito species, and have different types of chromosome-membrane links. The polytene chromosomes of the ovary sustentacular cells of Anopheles messeae Fall. were mapped cytogenetically, and were compared with the salivary gland chromosomes. There were no differences in the number of chromosomal bands, though the structures were "looser" in ovary sustentacular cells.
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