Department of Karyosystematics, Zoological Institute, Russian Academy of Sciences, Universitetskaya emb. 1, 199034 St. Petersburg, Russia.
Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Sławkowska 17, 31-016 Kraków, Poland.
Genes (Basel). 2023 Mar 15;14(3):725. doi: 10.3390/genes14030725.
The Lygaeoidea comprise about 4660 species in 790 genera and 16 families. Using standard chromosome staining and FISH with 18S rDNA and telomeric (TTAGG) probes, we studied male karyotypes and meiosis in 10 species of Lygaeoidea belonging to eight genera of the families Blissidae, Cymidae, Heterogastridae, Lygaeidae, and Rhyparochromidae. Chromosome numbers were shown to range from 12 to 28, with 2n = 14 being predominant. All species have an XY system and all but one have a pair of m-chromosomes. The exception is (Lygaeidae: Lygaeinae); in another species of Lygaeinae, , m-chromosomes were present, which represents the first finding for this subfamily. All species have an inverted sequence of sex chromosome divisions ("post-reduction"). The 18S rDNA loci were observed on one or both sex chromosomes in and , respectively (Lygaeidae), while on an autosomal bivalent in all other species. The rDNA loci tended to be close to the end of the chromosome. Using (TTAGG)-FISH, we were able to show for the first time that the Lygaeoidea lack the canonical "insect" telomere motif (TTAGG). We speculate that this ancestral motif is absent from the entire infraorder Pentatomomorpha being replaced by some other telomere repeat motif sequences.
菱蝽总科包含约 4660 种，隶属于 790 属和 16 科。我们使用标准染色体染色和 FISH 技术，用 18S rDNA 和端粒（TTAGG）探针研究了 10 种菱蝽总科的雄性染色体核型和减数分裂，这些物种隶属于菱蝽科、长蝽科、异蝽科、猎蝽科和沫蝉科的 8 个属。染色体数目范围为 12-28 条，以 2n = 14 为主。所有物种都具有 XY 系统，除一种外，所有物种都具有一对 m 染色体。例外是 （猎蝽科：猎蝽亚科）；在猎蝽亚科的另一个物种中，存在 m 染色体，这是该亚科的首次发现。所有物种的性染色体分裂都呈倒位序列（“减数后”）。在 和 中，分别观察到 18S rDNA 基因座位于一个或两个性染色体上（猎蝽科），而在其他所有物种中都位于一个常染色体二价体上。rDNA 基因座往往靠近染色体的末端。使用（TTAGG）-FISH，我们首次表明菱蝽总科缺乏经典的“昆虫”端粒基序（TTAGG）。我们推测，这个原始基序在整个半翅目下目 Pentatomomorpha 中缺失，被其他一些端粒重复基序序列所取代。
