[Isolation of ES-like lines of common voles of the genus Microtus from blastocysts and germ cells and as a result of the fusion of somatic cells with mouse embryonic stem cells]. / Poluchenie ES-podobnykh linii obyknovennykh polevok roda Microtus iz blastotsist, germinal'nykh kletok i ot sliianiia somaticheskikh kletok s émbryonal'nymi stvolovymi kletkami myshi.

Three and four independent cell lines with limited pluripotency were obtained from the inner cell mass cells of blastocysts and primordial germ cells of common voles, respectively. The results of cytogenetic analysis suggest that all these lines originated from the embryos of F1 Microtus rossiaemeridionalis x M. arvalis males and had a great number of near-triploid cells already during the early passages. The cells of these lines, like those of the inner cell mass, were characterized by the alkaline phosphatase activity. Nine independent cell lines were obtained as a result of hybridization of the mouse embryonic stem cells and vole splenocytes: eight lines and one line from hybridization with the M. kirgisorum and M. rossiaemeridionalis splenocytes, respectively. The cells of these lines expressed some properties of embryonic stem lines had a chromosome complement similar to the sum of two initial diploid sets of the mouse and vole.

[Phylogenetic relationships between 16 species of Lake Baikal sculpin fish based on a nucleotide sequence analysis of a mitochondrial DNA fragment of the cytochrome b gene]. / Filogeneticheskie vzaimootnosheniia sredi 16 vidov podkamenshchikovykh ryb oz. Baikal na osnove analiza nukleotidnoi posledovatel'nosti fragmenta gena tsitokhroma b mitokhondrial'noi DNK.

The fragment of mitochondrial cytochrome b gene from 16 species of Baikalian sculpins belonging to three families--Cottidae, Comephoridae and Abyssocottidae--was amplified by polymerase chain reaction and sequenced. Phylogenetic trees were built from data obtained. Some disconformity were noted between systematical and phylogenetic notions of today and obtained results. For example, branch lengths among some Cottidae species are larger than among any different family species. Moreover, schemes indicate separate position of Limnocottus euristomus from Limnocottus genus species. Phylogenetic trees confirm earlier conclusions, about recent--in geological scales of times--origin of baikalian Cottoidei (2-2.5 Myr).

[BspMII-family of tandemly organized DNA sequences of the Baikalian cottoid fish (Cottodei)]. / BspMII-semeistvo tandemno organizovannykh posledovatel'nostei DNK baikal'skikh kottoidnykh ryb (Cottoidei).

A new family of highly repetitive tandemly arrayed DNA sequences was revealed by electrophoretic analysis of BspMII (T'CCGGA) digest of genomic DNA from Baikalian cottoid fishes. Three such repeats from two species B. nikolskii and P. kneri were cloned and sequenced. The sizes of repeat elements are 238, 154, and 123 bp. All three repeats have highly homologous flanking regions 53 and 63 bp in length. It was shown that chains of DNA repeats had an ability to form stable secondary structures in vitro. It is supposed that shorter repeats (154 and 123 bp) originated from the 238 bp repeat by deletion its central fragments. An element having a the promoter for RNA polymerase III was found within the 238 bp repeat. The origin of this element from one of the tRNA genes is suggested. The possibility of using BspMII repeats as an evolutionary marker for studying the genesis of Cottoidei is discussed.

[Taxonometric analysis of DNA repeating elements]. / Taksonomicheskii analiz povtoriaiushchikhsia élementov DNK.

The method of analysis of low molecular weight fragments of high copied repeats of DNA hydrolysed by restriction nuclease is presented. The P labeled fragments (by means of DNA polymerase I) are electrophoresed in nondenaturing PAAG and radio-autographed. The specific band patterns are observed in region between approximately 20 and 300 bp. When studying some lizard and fish species DNA's it was shown that the patterns observed have species and genus specificity but not individual. The approach supposed can be applied to investigation of interspecies relationships, some evolutionary problems and to the studying of questions concerning the role of DNA repeats in evolution. The method is simple and comparatively cheap and may be called as "taxonomic DNA fingerprint" or "DNA taxonoprint" method.

[Use of high performance liquid chromatography for analysis of subfractions of lysine-rich histone H1 from Baikal fish--the sand sculpin Cottus kessleri Dyb]. / Primenenie vysokoéffektivnoi zhidkostnoi khromatografii dliia analiz subfraktsii lizin-bogatogo gistona H1 baikal'skogo bychka-peschanoi shirokolobki Cottus kessleri Dyb.

High performance liquid chromatography using PMSS-C18 resin was applied to separate variant-complicated histone H1 from liver of a Baikal lake endemic fish sand sculpin (Cottus Kessleri Dybow). Total H1 was resolved into 3 main fractions. One of them was resolved into two sub-fractions by rechromatography. All the fractions and sub-fractions obtained were studied for their amino acid composition. One of the subfractions (H1(3] contained no tyrosine residues, but very much (20%) proline. Hence, this subfraction may be a new type of lysine-rich histone H1.

[Microelectrophoretic analysis of histones from single chromosomes and nucleoli of mosquito (Chironomis plumosus) larvae]. / Mikroelektroforeticheskii analiz gistonov iz individual'nykh khromosom i iadryshek lichinki komara (Chironomus plumosus).

A simple method of microelectrophoresis for histone analysis from single fragments of polythenic chromosomes of chironomid salivary glands has been developed. The chromosomes or their fragments obtained micrurgically were dissolved in a microdroplet of 8 M urea and 1 N sulfuric acid solution. Electrophoresis was performed in 30--60 m diameter polyacrylamide gel cylinders under a layer of vaseline oil. The histones were separated into 6 electrophoretic bands which correspond to fractions H4, H2b, H2a+H3, H3-dimer, and two subfractions of histone H1. Comparison of histone electrophoregrams of the I, II, and III chromosomes showed their almost absolute identity. The ratio of fractions H4, H3, H2A, H2B as well as the ratio of histone H1 subfractions in the nucleus and in the rest of the IV chromosome cannot be visually distinguished.

[Functional activity of the salivary glands of Drosophila melanogaster in the course of metamorphosis: a comparative electrophoretic analysis of the proteins of the salivary glands, fat body and hemolymph]. / Funktsionl'naia aktivnost' sliumnykh zhelez Drosophila melanogaster v khode metamorfoza: sravnitel'nyi élektroforeticheskii analiz belkov sliunnykh zhelez, shirovogo tela i gemolimfy.

The proteins of the salivary gland secretion at the moment of puparium formation and the protein composition of the salivary glands, fat-body and hemolymph during the III larval instar and 12 hours prepupal period were investigated by means of electrophoresis in polyacrilamide gel, in the presence of urea. Both the qualitative and quantitative differences in the protein composition of the salivary glands were found which appeared to be due to the change of functions of the salivary glands in the process of development. 69 protein fractions were isolated in the salivary gland secretion, 40 of them being PAS-positive. A correlation was noted between the appearance of the first PAS-positive fractions at the stage of 95-100 hrs (from the moment of egg laying) and the cytological demonstration of PAS-positive secretion granules. New glycoproteins appeared in the salivary glands in prepupae (2 hrs after the puparium formation) and, later, in the hemolymph. A complicated pattern of the secretion formation in the salivary glands of the III instar larvae and possible change of its composition during metamorphosis are discussed.