The revision of chromosome III (EF) mapping in (Linnaeus, 1758) group (Diptera, Chironomidae).

A revision of mapping of main and alternative banding sequences in chromosome III (EF) has been made for 14 species of the group. In total, new versions of mapping are presented for 18 banding sequences of arm E and 18 banding sequences of arm F. A new way of tracing the origins of banding sequences in chromosome III of the group in comparison with basic banding sequences of the genus is suggested.

Redescription of larva, pupa and imago male of Chironomus (Chironomus) salinarius Kieffer from the saline rivers of the Lake Elton basin (Russia), its karyotype and ecology.

Cytology and ecology of Chironomus (Chironomus) salinarius Kieffer, 1915 (Diptera, Chironomidae) was examined from material collected in the saline rivers of the Lake Elton basin (Volgograd region, Russia). Larvae of salinarius-type were identified as C. salinarius on the basis of their karyotype.

A revision of chromosome II (CD) mapping in Chironomus plumosus (Linnaeus, 1758) group (Diptera, Chironomidae).

A revision of the main and alternative banding sequences in chromosome II (CD) has been made for all 14 species of the Chironomus plumosus (Linnaeus, 1758)group. A new version of mapping has been suggested for 10 out of 18 banding sequences of arm C and 12 out of 22 banding sequences of arm D. Mapping of 7 banding sequences has been done for the first time according to the Keyl-Devai system.

Karyotypes of Chironomus Meigen (Diptera: Chironomidae) species from Africa.

The karyotypes of six African Chironomus species (Chironomus alluaudi Kieffer, 1913, Chironomus transvaalensis Kieffer, 1923, Chironomus sp. Nakuru, Chironomus formosipennis Kieffer, 1908, Chironomus prope pulcher Wiedemann, 1830, Chironomus sp. Kisumu) were investigated; four of these karyotypes were described for the first time (Chironomus sp.

[Differentiation of chromosome banding sequence pools and genomic DNA in holarctic natural populations of Chironomus entis Shobanov (Diptera, Chironomidae)].

Polymorphism and differentiation of the chromosome banding sequence pools and genomic DNA were studied in three natural populations of Chironomus entis from Europe and North America. These populations showed a moderate level of chromosome polymorphism and high RAPD polymorphism of genomic DNA. The Palearctic and Nearctic populations of this species did not differ significantly in the levels of chromosome and genomic DNA polymorphism.

[Chromosomal variability in natural populations of Chironomus cingulatus Meigen (Diptera, Chironomidae)].

Chromosomal polymorphism has been investigated in 7 natural populations from West Europe, West Siberia and Sakha Republic (Yakutia). The pool of polytene chromosome banding sequences of this species includes 15 banding sequences. The chromosomal polymorphism has been revealed in 5 of chromosomal arms.

[Geographic differentiation of genomic DNA of Chironomus plumosus (Diptera, Chironomidae) in natural holarctic populations].

Using RAPD markers, polymorphism and differentiation of genomic DNA was examined in seven natural populations of Chironomus plumosus from Europe, Siberia, and North America. All these populations showed high polymorphism of genomic DNA. The Palearctic and Nearctic populations of this species were not statistically significantly different in the genomic DNA polymorphism level.

[The geographic varyability of the polytene chromosome banding sequence of non-biting midje Chironomus pseudothummi str. (Diptera, Chironomidae)].

The karyotypes and chromosomal polymorphism of Chironomus pseudothummi were investigated in different parts of its range. It was established that chromosomal variability in the natural populations of this species was represented mainly by the inversion polymorphism of arm G. Only rare and unique inversions were found as heterozygous in arms C, D, and E.

Polytene chromosomes and phylogenetic relationships of Chironomus atrella (Diptera: Chironomidae) in North America.

The identity of Chironomus atrella Townes has been confusing because the name has been used for at least 2 quite different species. This situation is clarified karyosystematically by describing the banding patterns and chromosomal polymorphisms from a number of locations in Canada and the US. Most populations show only moderate levels of polymorphism (average heterozygosity, 0.

[The chromosomal polymorphism and divergence of populations in Chironomus nuditarsis Str. (Diptera, Chironomidae)].

The karyotype structure and chromosomal polymorphisms were investigated in 6 natural and 2 laboratory populations of Chironomus nuditarsis from Europe and Asia. The pool of rearranged polytene chromosome banding sequences of this species was determined that includes 16 inversion banding sequences and sequences with giant DNA-knobs (ndtG1k, ndtG2k). Obvious differences were demonstrated in the level of chromosomal polymorphism between European and Asian (Siberian) populations: the former were highly polymorphic, while the latter were practically monomorphic.

[Karyotype structure in species of Propsilocerus genus (Diptera, Chironomidae)].

Karyotype structure and polytene chromosome banding patterns were studied in two Orthocladiinae siblings--Propsilocerus akamusi (China) and Propsilocerus jacuticus (Russia). Both species have haploid number of chromosome typical for Orthocladiinae (n = 3). An unusual structure of centromeric regions was observed in all three chromosomes of karyotypes in both species.

[Variation and divergence of multilocus genome markers in the species of the genus Chironomus (Diptera, Chironomidae)].

Variation and divergence patterns of the multilocus genome markers in twelve Chironomus species belonging to the plumosus and piger sibling-species groups were examined by use of polymerase chain reaction with random primers (RAPD method). The chironomid species showed high levels of the RAPD markers polymorphism. The genetic distances (GD) were determined between the species within the group of closely related species, as well as between the species from different groups.

[Divergence of the polytene chromosome banding sequences as a reflection of evolutionary rearrangements of the genome linear structure].

Banding sequences of five chromosomal arms (A, C, D, E, and F), accounting for about 70% of the total genome size in 63 Chironomus species, were used as phylogenetic markers to analyze divergence patterns of the linear genome structure during the evolution. The number of chromosomal breakpoints between the pairs of banding sequences compared served as a measure of divergence. It was demonstrated that the greater the divergence between the species compared, the higher the number of chromosomal breakpoints and the smaller the size of the conserved chromosomal regions.

[Molecular-cytogenetic characteristics of B-chromosomes in chironomid (Diptera, Chironomidae)].

Morphological and molecular study of B-chromosomes of three Chironomus species (siblings Ch. borokensis and Ch. phumosus from plumosus group, and Ch.

[Evidence of species specific pericentric inversion in the karyotype of the midge Chironomus balatonicus].

Pericentric inversions do not play any important role in chromosomal rearrangements in the karyotype evolution of the genus Chironomus. However, a unique case of the fixed pericentric inversion was discovered in chromosome 2 of Chironomus balatonicus--one of the members of plumosus-species group (Kikhadze et al., 1996a; Golygina et al.

[The functional morphology of polytene chromosomes in the midge Chironomus pilicornis F. from the permafrost zone reservoirs].

The karyotype and chromosomal polymorphism of Chironomus pilicornis from the reservoirs of Yakutian permafrost zone are described. In the Yakutian populations, of 10 inversion sequences 11 genotypical combinations of these were registered. The level of inversion heterozygosity is 50-70%, but in several populations it makes only 11-29%.

[Karyofund of Chironomus plumosus (Diptera, Chronomidae) in the Palearctic region].

Quantitative and qualitative analyses of chromosomal polymorphism in 38 Palearctic populations of Chironomus plumosus were made. It was shown that most of the populations studied were highly polymorphic: in average 63.2 +/- 4.

Polyploidization in the trophoblast and uterine glandular epithelium of the endotheliochorial placenta of silver fox (Vulpes fulvus Desm.), as revealed by the DNA content.

Dynamics of genome multiplication during establishment of interrelations between trophoblast and glandular epithelium of the endometrium has been studied in the course of formation of placenta in the silver fox. During formation of the placenta, penetration of the trophoblast into the zone of the endometrial glandular epithelium and of endometrial blood vessels into the zone of expanding trophoblast occurs. The trophoblast, which gradually replaces epithelium and a part of the stroma of the endometrium, closely adjoins endometrial vessels but does not disrupt them, thereby the endotheliochorial placenta is formed.

Intercontinental karyotypic differentiation of Chironomus entis Shobanov, a Holarctic member of the C. plumosus group (Diptera, Chironomidae).

Analysis of banding sequences of polytene chromosomes in Palearctic (Russian) and Nearctic (North American) Chironomus entis shows strong karyotype divergence between populations on the two continents. Four out of seven chromosomal arms in the North American C. entis karyotype are characterized by sequences found only in the Nearctic.

[Genome multiplication in the trophoblasts and glandular epithelium of endometrium during embryo implantation and placentation of silver fox].

Dynamics of genome multiplication during establishment of interrelations between the trophoblast and the glandular epithelium of endometrium was studied in the course of placenta formation in the silver fox. Endometrium response on the embryo implantation exhibits some features of inflammation. In the course of placenta formation the trophoblast gains access to the endometrial glandular epithelium zone, while the endometrial blood vessels grow the other way into the expanding trophoblast zone.

[Karyotype of the midge Chironomus heterodentatus Konstantinov from the group Obtusidens (Diptera, Chironomidae)].

The karyotype of Chironomus heterodentatus, belonging to the obtusidens-group described by Konstantinov from the Volga in 1956, was studied in detail. Combinations of chromosomal arms are AB, CD, EF and G (cytocomplex thummi). The Ch.

[Divergence of karyofunds in sibling species of the plumosus group (Diptera: Chironomidae)].

Cytogenetic differentiation of eight sibling species of the plumosus group was examined. The karyofunds of these sibling species were shown to diverge incompletely. In each species karyofund, the banding sequences homologous to those of the remaining species of this group were revealed.

Centromeric heterochromatin and satellite DNA in the Chironomus plumosus species group.

Species of the Chironomus plumosus group display significant differences in their amount of centromeric heterochromatin. A tandem-repetitive satellite-like DNA has been isolated from C. plumosus.

[Polyploid mitoses in mink trophoblast cells].

Mitotic figures in the mink placental trophoblasts have been observed under the light microscope using actions and air-dried preparations. The tetra- and octaploid metaphase chromosome spreads were found on Giemsa-stained air-dried preparations. A high percentage (up to 80%) of abnormal metaphases, including k-mitoses as well as a portion of restitution anaphases, was revealed on sections of the placental trophoblast suggesting a possible block of mitosis at the meta- and anaphase.

[Polyploidy and polyteny in the trophoblast cells of the mink].

According to cytophotometry, trophoblast cells in the mink placenta are both diploid and polyploid, the ploidy level ranging from 2c to 64c. A great number of mink trophoblast cells were seen to divide mitotically. In addition to the ordinary mitotic figures, polyploid mitoses as well as abnormal mitotic figures were observed.