Juan C, Vazquez P, Rubio J M, Petitpierre E, Hewitt G M
Departament de Biologia Ambiental, Universitat de les Illes Balears, Palma de Mallorca, Spain.
Heredity (Edinb). 1993 Jan;70 ( Pt 1):1-8. doi: 10.1038/hdy.1993.1.
Digestion of genomic DNA from seven species of Tribolium (Coleoptera) with Sau3AI, TaqI and ClaI restriction enzymes shows the presence of remarkable amounts of highly repetitive DNA sequences in these species. In Tribolium freemani the sequences are tandemly repeated with a satellite monomer of 166 bp, A-T rich (70.5 per cent), representing 31 per cent of the total genome and located in centromeric chromosome areas as demonstrated by in situ hybridization. The sequence has the potential to form secondary structures such as stems or cruciforms due to the presence of frequent inverted repeats. Tribolium castaneum, T. anaphe and T. madens show homologous sequences to T. freemani satellite DNA but T. confusum, T. audax, T. brevicornis and other tenebrionid beetles, such as Tenebrio molitor and Misolampus goudoti, do not. A phylogenetic dendrogram, based on the homology and abundance of highly repetitive sequences deduced by dot-blot hybridization, chemotaxonomic and karyological characters, is proposed for the seven studied species of Tribolium.
用Sau3AI、TaqI和ClaI限制性内切酶消化七种拟步甲属（鞘翅目）昆虫的基因组DNA，结果表明这些物种中存在大量高度重复的DNA序列。在弗里曼拟步甲中，这些序列以166 bp的卫星单体串联重复，富含A-T（70.5%），占基因组总量的31%，原位杂交显示其位于着丝粒染色体区域。由于存在频繁的反向重复序列，该序列有可能形成茎或十字形等二级结构。赤拟谷盗、阿纳菲拟步甲和马登斯拟步甲显示出与弗里曼拟步甲卫星DNA的同源序列，但杂拟谷盗、奥达克斯拟步甲、短角拟步甲以及其他拟步甲科甲虫，如黄粉虫和古氏米索步甲，则没有。基于斑点杂交推断的高度重复序列的同源性和丰度、化学分类学和核型特征，为七种研究的拟步甲属物种构建了系统发育树状图。
