Relationships and position of the taxa of the subfamily Xiphisterinae in the system of the suborder Zoarcoidei (Perciformes)

Analysis of the nucleotide sequences of mitochondrial and nuclear DNA genes was used to examine the relationships and position of the subfamily Xiphisterinae in the system of the suborder Zoarcoidei. This study showed the genetic heterogeneity of Xiphisterinae and the propriety of its division into two subfamilies: Xiphisterinae with the genera Xiphister and Phytichthys and Cebidichthyinae with the genera Cebidichthys, Dictyosoma, Esselenichthys, and Nivchia. The genetic differences between the two subfamilies were not less, but in some cases even greater than the differences between families within the suborder; therefore, they should be raised to the rank of a family, Xiphisteridae and Cebidichthyidae, and classified not within the superfamily Stichaeoidae but rather as independent taxa of the suborder Zoarcoidei.     

Foregut Mesenchyme Contributes Cells to Islets during Pancreatic Development in a 3-Dimensional Avian Model

Current interest in the potential use of pancreatic stem-cells in the treatment of insulin dependent diabetes mellitus has led to increased research into normal pancreatic development. Pancreatic organogenesis involves branching morphogenesis of undifferentiated epithelium within surrounding mesenchyme. Current understanding is that the pancreatic islets develop exclusively from the epithelium of the embryonic buds. However, a cellular contribution to islets by mesenchyme has not been conclusively excluded. We present evidence that the mesenchyme of both the dorsal pancreatic bud and stomach rudiment make a substantial contribution of cells to islets during development in a three-dimensional avian model. These data suggest that mesenchyme can be a source not only of signals but also of cells for the definitive epithelia, making pancreatic organogenesis more akin to that of the kidney than to other endodermal organs. This raises the possibility for the use of mesenchymal cells as stem-or progenitor-cells for islet transplantation.Key Words: islets, stem-cells, development, epithelium, mesenchyme, pancreas, stomach, chick-quail, 3-dimensional, endocrine     

Ants of the Genus <Emphasis Type="Italic">Fallomyrma</Emphasis> Dlussky et Radchenko (Hymenoptera,Formicidae, Myrmicinae) from Late Eocene European Ambers

The extinct monotypic ant genus Fallomyrma was described by Dlussky and Radchenko in 2006 based on workers from Late Eocene Rovno (Ukraine), Scandinavian (Denmark), and Bitterfeld (Germany) ambers. Three new Fallomyrma species from the Rovno amber are here described based on workers: F. anodonta sp. nov., F. marginata sp. nov., and F. robusta sp. nov. A key to all known species of this genus is compiled. The quantity ratios (of the numbers of species and specimens) of Fallomyrma and other amber Myrmicinae genera are considered. The opinion of the autochthonous origin of the Rovno amber is confirmed.     

Molecular genetic and karyological analysis of antlered sculpins of <Emphasis Type="Italic">Enophrys diceraus</Emphasis> group (Cottidae)

Molecular genetic and karyological analyses of antlered sculpin, Enophrys diceraus, from the Sea of Japan and the Sea of Okhotsk were carried out. The karyotype of this species was studied for the first time. On the basis of karyological analysis, it was established that E. diceraus from the Sea of Japan and the Sea of Okhotsk was polymorphic in terms of the number of chromosomes and their morphology (2n = 36, 35, and 37, NF = 40). It was suggested that the karyotype with 35 chromosomes could have been produced as a result of Robertsonian translocation; the karyotype with 37 chromosomes could have been produced by crossing of individuals with different number of chromosomes. On the basis of the molecular genetic analysis of the mitochondrial COI and 16S rRNA genes, considerable differences between E. diceraus from the Sea of Japan and the Sea of Okhotsk corresponding to the level of interspecies genetic variability were established. It is concluded that E. diceraus from the Sea of Japan belongs to another species, most likely, E. namiyei.     

Protein complex Ppz1p/Hal3p and the efficiency of nonsense suppression in yeasts <Emphasis Type=Italic>Saccharomyces cerevisiae</Emphasis>

It is known that the efficiency of nonsense suppression in yeasts is controlled both genetically and epigenetically. Since many components of translation machinery are represented by phosphoproteins, the efficiency depends, in particular, on the activity of kinases and phosphatases that include the Ppz1p/Hal3p complex. It contains Ppz1p phosphatase, which is a catalytic subunit, and Hal3p that negatively regulates its function. The aim of this work was to study the mechanisms which relate the activity of Ppz1p/Hal3p complex to nonsense suppression efficiency. In this study, we used a genetic approach implicating the analysis of nonsense suppression phenotype of the strains overexpressing HAL3 or PPZ1 genes and also bearing deletions or mutant alleles of genes, which presumably could participate in the manifestation of these overexpressions. We have shown that Hal3p inhibits not only Ppz1p but also the homologous phosphatase Ppz2p. Our data indicate that Ppz2p is also involved in the control of nonsense suppression efficiency. In the course of search for Ppz1p target protein, it was shown that Ppz1p dephosphorylates at least two proteins involved in translation. Moreover, Ppz1p affects the efficiency of nonsense suppression not only due to its phosphatase activity but also due to another mechanism triggered by its interaction with Hsp70 chaperones.     

The ant <Emphasis Type="Italic">Aphaenogaster dlusskyana</Emphasis> sp. nov. (Hymenoptera,Formicidae) from the Sakhalin amber—the earliest described species of an extant genus of Myrmicinae

The earliest member of an extant ant genus of the subfamily Myrmicinae, Aphaenogaster dlusskyana sp. nov., from the Sakhalin amber (Russia, Middle Eocene, 43–47 Ma) is described. Fossil representatives of the genus Aphaenogaster are critically analyzed and it is proposed to transfer many of these to the fossil morphotaxon Paraphaenogaster. The morphology, distribution, and possible evolutionary trends of the genus Aphaenogaster are reviewed and it is suggested that this genus appeared in the territory currently occupied by the Palearctic not later than the Early Eocene (over 50 Ma). Aphaenogaster dlusskyana can be considered the oldest described representative of an extant genus of the subfamily Myrmicinae, although earlier, as yet undescribed, records of extant genera of Myrmicinae belong to the Early Eocene.     

The subfamily Myoxocephalinae of cottid fishes (Cottidae): Genetic divergence and phylogenetic relationships

A comprehensive study based on molecular marker and karyotype analyses has provided evidence for the monophyly of the subfamily Myoxocephalinae, which includes the genera Myoxocephalus, Megalocottus, Microcottus, Porocottus, Enophrys and Argyrocottus. In addition, the karyotype of the threadfoot sculpin Argyrocottus zanderi Herzenstein 1892 has been studied for the first time. Marker traits of karyotypes identified 13 species among six cottid genera. As the molecular genetic results confirmed, the subfamily is divided into two groups corresponding to Enophrys and Myoxocephalus. The molecular genetic data did not support the formation of tribes within the subfamily Myoxocephalinae, as proposed earlier based on morphological characters. Moreover, the genera Trichocottus and Taurocottus should be excluded from the Myoxocephalinae. The evolutionary transformations of karyotypes in cottid fish tended towards a reduction in the number of chromosomes and chromosome arms.     

Ants (Hymenoptera,Formicidae) of Kyiv

Entomological Review - Altogether, 59 ant species from 22 genera of 4 subfamilies have been recorded in Kyiv. Four of them are occasionally introduced species which occur only in premises heated in...     

Variation of cytochrome b gene in sympatric chars from kronotsky lake (Kamchatka Peninsula)

In previously identified sympatric char forms (species) from Kronotsky Lake (Kamchatka Peninsula) and a number of other chars from the genus Salvelinus, nucleotide sequences of the mtDNA cytochrome b gene were determined and phylogenetic analysis of these chars was performed. The divergence estimate of the cytochrome b gene in the Kronotsky char group (0.48%) coincided with the interpopulation difference estimates in northern Dolly Varden, which indicates a relatively recent divergence of the chars from Kronotsky Lake. Haplotypes of each form of the Kronotsky Lake chars are divided into two groups, which belonged to two different phylogenetic mtDNA lineages of northern Dolly Varden from Chukotka and Kamchatka. The formation of the Kronotsky char forms proved to be unrelated to the observed variability of the mtDNA cytochrome b gene.