The characteristics of karyotype and telomeric satellite DNA sequences in the cricket, <i>Gryllus bimaculatus</i> (Orthoptera, Gryllidae)

Abstract

The chromosomes derived from the Japanese population of Gryllus bimaculatus were characterized by C-banding and Ag-NOR staining. The chromosome number, 2n = 28 + XX (female)/XO (male), corresponded with that of other populations of G. bimaculatus, but the chromosome configuration in idiograms varied between the populations. NORs were carried on one pair of autosomes and appeared polymorphous. The positive C-bands located at the centromere of all chromosomes and the distal regions of many chromosome pairs, and the size and the distribution pattern of the distal C-heterochromatin showed differences among the chromosomes. In addition, this paper reports on the characteristics of HindIII satellite DNA isolated from the genome of G. bimaculatus. The HindIII repetitive fragments were about 0.54 kb long, and localized at the distal C-bands of the autosomes and the interstitial C-bands of the X chromosome. Molecular analysis showed two distinct satellite DNA sequences, named the GBH535 and GBH542 families, with high AT contents of about 67 and 66%, respectively. The two repetitive families seem to be derived from a common ancestral sequence, and both families possessed the same 13-bp palindrome sequence. The results of Southern blot hybridization suggest that the sequence of the GBH535 family is conserved in the genomic DNAs of Gryllus species, whereas the GBH542 family is a species-specific sequence.

Molecular evolution of the pDo500 satellite DNA family in Dolichopoda cave crickets (Rhaphidophoridae)

“…Unfortunately, very few other examples are found in the literature with both fast-evolving and slowly-evolving satDNAs found within the same species e.g. [69,70]. …”

Satellite DNA in insects: a review

“…The two speciesspecific satDNA families from the grasshopper Oxya hyla showed similar sequence variability (Yoshimura et al, 2006a). The two satDNAs from the cricket G. bimaculatus also showed similar sequence variability, although one is species specific and the other is present in different congeneric species (Yoshimura et al, 2006b). However, the pBuM-1 and pBuM-2 evolutionarily related satDNA subfamilies from the D. buzzatii species cluster (repleta group) showed different sequence variability, indicating a slower rate of evolution of the pBuM-2 subfamily (Kuhn and Sene, 2005).…”

“…In relation to its specific distribution (Table 1 in Supplementary information), satDNA is sometimes species specific, as in the case of the 542-bp satDNA from Gryllus bimaculatus (Yoshimura et al, 2006b), whereas other variants are shared among more or less related species, such as the 180-bp satDNA from Drosophila ambigua, which is also present in D. tristis and D. obscura (Bachmann and Sperlich, 1993). It bears mentioning that certain satDNAs that are presently considered species specific may actually be present in other related species, in low copy number detectable only by PCR assays, as discussed below.…”

Telomere structure in insects: A review

“…Orthoptera are subdivided into two suborders, i.e., Caelifera, with approximately 11,000 species, including grasshoppers and locusts (Acrididae), and Ensifera (about 9,000 species), which includes crickets and katydids (Song et al, 2015). Up to now, telomere structure of 59 species (including three subspecies of a particular species) in 34 genera belonging to both Caelifera (the families Acrididae, Pamphagidae, and Pyrgomorphidae) and Ensifera (Raphidiophoridae, Gryllidae, and Tettigoniidae) was studied (Bueno, Palacios-Gimenez, & Cabral-de-Mello, 2013;Buleu et al, 2019;Frydrychová et al, 2004;Jetybayev, Bugrov, Dzuybenko, & Rubtsov, 2018;Jetybayev et al, 2012;Kociński et al, 2018;Kojima, Kubo, & Fujiwara, 2002;López-Fernández, Arroyo, Fernández, & Gosálvez, 2006;López-Fernández et al, 2004;Okazaki et al, 1993;Sahara et al, 1999;Vitturi, Lannino, Mansueto, Mansueto, & Colomba, 2008;Warchałowska-Śliwa, Grzywacz, Maryańska-Nadachowska, Hemp, & Hemp, 2015;Warchałowska-Śliwa et al, 2009;Yoshimura, Nakata, Mito, & Noji, 2006). The (TTAGG) n telomere motif apparently presents in all members of both major orthopteran lineages, and is therefore presumed the ancestral telomere motif in the order in general.…”