Karyology of the Antarctic scallop Adamussium colbecki, with some comments on the karyological evolution of pectinids

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• 作者：G. Odierna ; G. Aprea ; M. Barucca ; A. Canapa ; T. Capriglione and E. Olmo
• 关键词：Adamussium colbecki ; chromosomes ; intraindividual mosaicism ; karyotype ; rearrangements
• 刊名：Genetica
• 出版年：2006
• 出版时间：May, 2006
• 年：2006
• 卷：127
• 期：1-3
• 页码：341-349
• 全文大小：378 KB

文摘

Karyotype, location of the nucleolar organiser region (NOR) and heterochromatin presence and composition were studied in the Antarctic scallop Adamussium colbecki Smith, 1902. The karyotype exhibits 2n = 38 chromosomes with 11 pairs of metacentrics, 5 of submetacentrics, one subtelocentric and two telocentrics. Ag–NOR, CMA₃, DA/MM and NOR–FISH evidenced paracentromeric NORs on the short arm of 2nd pair chromosomes. Digestion with three restriction endonucleases followed by sequential staining with Giemsa, CMA₃ and DAPI evidenced on all chromosomes centromeric heterochromatin positive for both DAPI and CMA₃. In situ hybridisation analysis showed the presence of an AT-rich satellite DNA in the centromeric heterochromatin of several chromosomes. A mosaicism was detected in the germinal cell lines of one specimen, as in six of the 20 plates examined the set had 37 chromosomes with a missing pair of telocentrics and an unpaired metacentric. Comparison of the chromosome sets of all the pectinids studied to date and comparison with a phyletic tree obtained from molecular mitochondrial genes studies yielded good agreement between karyotype morphology and taxonomic classification.