Number and location of rDNA clusters in the superfamilies Tenthredinoidea and Cynipoidea (Hymenoptera): an update.

To identify nucleolus organizing regions (NORs), fluorescence hybridization (FISH) with 18S rDNA probe was performed on chromosomes of Linnaeus, 1758 (Tenthredinidae), (Linnaeus, 1767) (Argidae) (n = 10 in both) and (Bouché, 1834) (Cynipidae) (2n = 20). In all these species, a single pericentromeric rDNA cluster per haploid karyotype was detected. This number of NORs is confirmed as ancestral for the order Hymenoptera.

The First FISH-Confirmed Non-Canonical Telomeric Motif in Heteroptera: Linnaeus, 1758 and (Fabricius, 1803) (Hemiptera, Cimicidae) Have a 10 bp Motif (TTAGGGATGG).

Fluorescence in situ hybridization (FISH) with two different probes, the canonical insect telomeric sequence (TTAGG) and the sequence (TTAGGGATGG), was performed on meiotic chromosomes of two members of the true bug family Cimicidae (Cimicomorpha), the common bed bug Linnaeus, 1758 and the tropical bed bug . (Fabricius, 1803), whose telomeric motifs were not known. In both species, there were no hybridization signals with the first probe, but strong signals at chromosomal ends were observed with the second probe, indicating the presence of a telomeric motif (TTAGGGATGG).

Karyotype diversity in the genus Dallas, 1852 (Hemiptera, Heteroptera, Lygaeidae) is much greater than you might think.

We studied the karyotype and chromosomal distribution of 18S rDNA clustered in nucleolar organizer regions (NORs) in (Kolenati, 1845), belonging to the subfamily Orsillinae (Lygaeidae). It is shown that this species has a karyotype with 2n = 22(18+mm+XY), previously known in only one of 24 studied species of the genus Dallas, 1852, characterized by a similar karyotype, 2n = 14(12+mm+XY). In , 18S loci are located on sex chromosomes, which is a previously unknown trait for this genus.

Expanding the Chromosomal Evolution Understanding of Lygaeioid True Bugs (Lygaeoidea, Pentatomomorpha, Heteroptera) by Classical and Molecular Cytogenetic Analysis.

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.

Comparative Cytogenetics of Lace Bugs (Tingidae, Heteroptera): New Data and a Brief Overview.

The lace bug family Tingidae comprises more than 2600 described species in 318 genera that are classified into the subfamilies Tinginae (about 2500 species and 300 genera), Cantacaderinae, and Vianadinae. We provide data on karyotypes of 16 species belonging to 10 genera of the tribes Tingini and Acalyptaini (Tinginae) studied using conventional chromosome staining and FISH. The species of Tingini possess 2n = 12A + XY, whereas those of Acalyptaini have 2n = 12A + X(0).

New evidence for the presence of the telomere motif (TTAGG) in the family Reduviidae and its absence in the families Nabidae and Miridae (Hemiptera, Cimicomorpha).

Male karyotype and meiosis in four true bug species belonging to the families Reduviidae, Nabidae, and Miridae (Cimicomorpha) were studied for the first time using Giemsa staining and FISH with 18S ribosomal DNA and telomeric (TTAGG) probes. We found that (Herrich-Schäffer, 1846) and (Poda, 1761) (Reduviidae: Harpactorinae) had 2n = 28 (24 + XXXY), whereas Dohrn, 1862 (Nabidae) and (Gmelin, 1790) (Miridae) had 2n = 34 (32 + XY) and 2n = 32 (30 + XY), respectively. FISH for 18S rDNA revealed hybridization signals on a sex chromosome, the X or the Y, in , on both X and Y chromosomes in , and on two of the four sex chromosomes, Y and one of the Xs, in both species of Hahn, 1834.

Proteolytic and nonproteolytic activation mechanisms result in conformationally and functionally different forms of coagulation factor XIII A.

Factor XIIIA (FXIIIA) is a transglutaminase that cross-links intra- and extracellular protein substrates. FXIIIA is expressed as an inactive zymogen, and during blood coagulation, it is activated by removal of an activation peptide by the protease thrombin. No such proteolytic FXIIIA activation is known to occur in other tissues or the intracellular form of FXIIIA.

FISH-based karyotyping of (Pallas, 1766), Schulze, 1914, and Itô, 1947 (Cnidaria, Hydrozoa).

An account is given of the karyotypes of Itô, 1947, Schulze, 1914, and (Pallas, 1766) (Cnidaria, Hydrozoa, Hydridae). A number of different techniques were used: conventional karyotype characterization by standard staining, DAPI-banding and C-banding was complemented by the physical mapping of the ribosomal RNA (18S rDNA probe) and H3 histone genes, and the telomeric (TTAGGG) sequence by fluorescence hybridization (FISH). We found that the species studied had 2n = 30; constitutive heterochromatin was present in the centromeric regions of the chromosomes; the "vertebrate" telomeric (TTAGGG) motif was located on both ends of each chromosome and no interstitial sites were detected; 18S rDNA was mapped on the largest chromosome pair in and on one of the largest chromosome pairs in and ; in , the major rRNA and H3 histone multigene families were located on the largest pair of chromosomes, on their long arms and in the centromeric areas respectively.

Cytogenetic Characterization of Eight Odonata Species Originating from the Curonian Spit (the Baltic Sea, Russia) Using C-Banding and FISH with 18S rDNA and Telomeric (TTAGG)n Probes.

We studied the karyotypes of 8 dragonfly species originating from the Curonian Spit (the Baltic Sea, Russia) using C-banding and FISH with 18S rDNA and "insect" telomeric (TTAGG)n probes. Our results show that Leucorrhinia rubicunda, Libellula depressa, L. quadrimaculata, Orthetrum cancellatum, Sympetrum danae, and S.

Activation of factor XIII is accompanied by a change in oligomerization state.

Unlabelled: Factor XIII A (FXIIIA) is a member of the transglutaminase enzyme family that cross-links both intra- and extracellular protein substrates. To prevent undesired cross-linking, FXIIIA is expressed as an inactive zymogen and exists intracellularly as an A homodimer. In plasma, FXIII A is complexed with two protective factor XIII B subunits (A B ) that dissociate upon activation of the zymogen.

Screening cleavage of Factor XIII V34X Activation Peptides by thrombin mutants: A strategy for controlling fibrin architecture.

In blood coagulation, thrombin converts fibrinogen into fibrin monomers that polymerize into a clot network. Thrombin also activates Factor XIII by cleaving the R37-G38 peptide bond of the Activation Peptide (AP) segment. The resultant transglutaminase introduces covalent crosslinks into the fibrin clot.

Cytogenetic study on antlions (Neuroptera, Myrmeleontidae): first data on telomere structure and rDNA location.

Myrmeleontidae, commonly known as "antlions", are the most diverse family of the insect order Neuroptera, with over 1700 described species (in 191 genera) of which 37 species (in 21 genera) have so far been studied in respect to standard karyotypes. In the present paper we provide first data on the occurrence of the "insect-type" telomeric repeat (TTAGG) and location of 18S rDNA clusters in the antlion karyotypes studied using fluorescence hybridization (FISH). We show that males of (Linnaeus, 1764) (Palparinae), (Villers, 1789) (Acanthaclisinae) and (Fabricius, 1798) (Nemoleontinae) have rDNA clusters on a large bivalent, two last species having an additional rDNA cluster on one of the sex chromosomes, most probably the X.

Karyotype stability in the family Issidae (Hemiptera, Auchenorrhyncha) revealed by chromosome techniques and FISH with telomeric (TTAGG) and 18S rDNA probes.

We report several chromosomal traits in 11 species from 8 genera of the planthopper family Issidae, the tribes Issini, Parahiraciini and Hemisphaeriini. All species present a 2n = 27, X(0) chromosome complement known to be ancestral for the family. The karyotype is conserved in structure and consists of a pair of very large autosomes; the remaining chromosomes gradually decrease in size and the X chromosome is one of the smallest in the complement.

First evidence for (TTAGG)n telomeric sequence and sex chromosome post-reduction in Coleorrhyncha (Insecta, Hemiptera).

Telomeric repeats are general and significant structures of eukaryotic chromosomes. However, nothing is known about the molecular structure of telomeres in the enigmatic hemipteran suborder Coleorrhyncha (moss bugs) commonly considered as the sister group to the suborder Heteroptera (true bugs). The true bugs are known to differ from the rest of the Hemiptera in that they display an inverted sequence of sex chromosome divisions in male meiosis, the so-called sex chromosome post-reduction.

Ribosomal DNA clusters and telomeric (TTAGG)n repeats in blue butterflies (Lepidoptera, Lycaenidae) with low and high chromosome numbers.

Ribosomal DNA clusters and telomeric repeats are important parts of eukaryotic genome. However, little is known about their organization and localization in karyotypes of organisms with holocentric chromosomes. Here we present first cytogenetic study of these molecular structures in seven blue butterflies of the genus Polyommatus Latreille, 1804 with low and high chromosome numbers (from n=10 to n=ca.

Homoploid hybrid speciation and genome evolution via chromosome sorting.

Genomes of numerous diploid plant and animal species possess traces of interspecific crosses, and many researches consider them as support for homoploid hybrid speciation (HHS), a process by which a new reproductively isolated species arises through hybridization and combination of parts of the parental genomes, but without an increase in ploidy. However, convincing evidence for a creative role of hybridization in the origin of reproductive isolation between hybrid and parental forms is extremely limited. Here, through studying Agrodiaetus butterflies, we provide proof of a previously unknown mode of HHS based on the formation of post-zygotic reproductive isolation via hybridization of chromosomally divergent parental species and subsequent fixation of a novel combination of chromosome fusions/fissions in hybrid descendants.

Distribution of 18S rDNA sites and absence of the canonical TTAGG insect telomeric repeat in parasitoid Hymenoptera.

Karyotypes of six species belonging to three main clades of parasitoid Hymenoptera, the superfamilies Ichneumonoidea (Ichneumonidae: Ichneumon amphibolus), Cynipoidea (Cynipidae: Diplolepis rosae) and Chalcidoidea (Eurytomidae: Eurytoma robusta, Eu. serratulae and Eu. compressa, and Torymidae: Torymus bedeguaris) were studied using FISH with 18S rDNA and telomeric (TTAGG)n probes.

The first finding of (TTAGG)n telomeric repeat in chromosomes of true bugs (Heteroptera, Belostomatidae).

Using the fluorescence in situ hybridization (FISH), the presence of (TTAGG)n telomeric sequence was detected in the chromosomes of Lethocerus patruelis (Stål, 1854) belonging to the family Belostomatidae (Heteroptera: Nepomorpha). This sequence was exclusively present at the ends of chromosomes in this species. This is the first evidence of the insect-type TTAGG telomeric repeats in Heteroptera.