Relationships of eelpouts of the genus <Emphasis Type="Italic">Zoarces</Emphasis> (Zoarcidae,Pisces) inferred from molecular genetic and morphological data

Abstract-Molecular genetic and morphological analysis of eelpouts of the genus Zoarces was carried out. Based on the mitochondrial DNA sequence variation, haplotypes of notched-fin eelpout, Z. elogatus, more closely related Fedorov eelpout, Z. fedorovi, and common eelpout, Z. viviparus, as well as of Andriyashev eelpout, Z. andriashevi, were grouped in one macrocluster. Haplotypes of American eelpout, Z. americanus, and blotched eelpout, Z. gillii, clustered separately from other species. The genetic differences between Z. gillii and the other eelpout species were very high for within-genus comparisons, constituting 7.62%. Species divergence in terms of morphological characters was generally consistent with molecular genetic data and confirmed distinct isolation of American eelpout, and especially of blotched eelpout.     

Restriction fragment variation of the mitochondrial gene of cytochrome b in some taxa of the Eelpout Family (Pisces, Perciformes, Zoarcidae) from the northern Sea of Okhotsk

The first analysis of restriction fragment length polymorphism (RFLP) of the mitochondrial gene of cytochrome b of fish from the Eelpout Family (Zoarcidae) from the northern Sea of Okhotsk has been performed. The mean genetic distances between the subfamilies Zoarcinae and Lycodinae, subfamilies Lycodinae and Gymnelinae, and subfamilies Zoarcinae and Gymnelinae are 11.14, 13.87, and 14.00%, respectively. Species of the genus Lycodes (Lycodinae) are characterized by a mtDNA small divergence (on average, 2.04%) and are divided into two groups on the basis of lateral line morphology. Magadania skopetsi, an endemic of Tauiskaya Bay of the Sea of Okhotsk, is genetically close to Hadropareia middendorffii from the same subfamily (Gymnelinae). The mtDNA sequences of species from the genus Lycogrammoides (Lycodinae) differ by 3.83%. The genetic differences between the eelpout Zoarces elongatus Zoarces sp. (d = 4.54%) suggest that the latter is a separate species.     

Differences Between two Subspecies of Dolly Varden, Salvelinus malma, Revealed by RFLP—PCR Analysis of Mitochondrial DNA

Genetic differences between two subspecies of Dolly Varden, northern Salvelinus malma malma and southern Salvelinus malma krascheninnikovi, from rivers of eastern Russia were studied. Mitochondrial DNA was analyzed by restriction fragment length polymorphisms (RFLP) performed on products amplified with polymerase chain reaction. Three adjacent segments (approximately 7670 bp), comprising 47% of the mitochondrial genome were used: two encoding the five complete NADH dehydrogenase subunits and the other the cytochrome b gene and the control region (D-loop). Total composite haplotypes 46 were found among 136 fishes using RFLP analysis with 14 restriction enzymes. The amount of nucleotide divergence between haplotypes of two subspecies of Dolly Varden was estimated to be approximately 4%. The differences in the level of nucleotide diversity, mismatch distribution between haplotypes, and population-genetic structure of two subspecies of Dolly Varden suggest that these two forms have existed separately for a long time.     

Relationships and divergence of some taxa of the subfamily Lycodinae (Zoarcidae,Pisces) based on molecular-genetic and morphological data

An integrated molecular-genetic and morphological study of 14 species of 6 genera of Zoarcidae of the subfamily Lycodinae was performed. A high coincidence of study results obtained using both methods was found. The generic independence of the genus Petroschmidtia that includes species P. albonotata and P. toyamensis was justified. It was shown that species L. schmidti and L. nigrocaudatus belong to the genus Lycogrammoides; and the generic status of the genus Bothrocarichthys with species B. microcephalus and of the genus Allolepis with species A. hollandi was restored. The studied taxa fall into three large monophyletic groups that include species of the genus Petroschmidtia, species of the genus Lycodes, and species of the genera Bothrocara, Allolepis, Bothrocarichthys, and Lycogrammoides. Taxa of the last group are characterized by a large complex of morphological differences from the first two groups, including the absence of ventral fins. A key to species and genera of Lycogrammoides and Bothrocarichthys was compiled. The problem of determination of the time of divergence of the studied zoarcid-like fish using the concept of “molecular clock” and its calibration according to paleontological and paleogeographic data is discussed.     

Impact of bacterial autoregulatory molecules (homoserine lactones and alkylhydroxybenzenes) on the oxidative metabolism of the cell effectors of natural immunity

We investigated the impact of bacterial regulators homoserine lactones (HSLs) and alkylhydroxybenzenes (AHBs) (which are present in human fluids at pico- and nanomolar concentrations) on neutrophile oxidative metabolism. The HSL and AHB effects were determined using a test based on induced luminol-dependent chemoluminescence of neutrophiles in human peripheral blood. In this test, neutrophiles were preincubated with chemical analogs of bacterial autoregulators with different lengths of the hydrocarbon radical, such as HSL · HCl, C6- and C12-HSL, and C1-, C6-, and C12-AHB. We revealed that they suppressed the chemoluminescence and, accordingly, the oxidative metabolism of neutrophiles. This effect was more significant with HSLs than with AHBs. Within each of the two groups, the effect increased with an increase in the length of the hydrocarbon chain of the homologues. High concentrations of long-chain autoregulators of both types produce a cytotoxic effect that is associated with apoptosis in the case of C12-HSL and with cell membrane damage in the case of C12-AHB. The effects of low HSL and AHB concentrations involve their protein-modifying properties and result in changes in the activities of neutrophile oxidative enzymes. To a lesser extent, these effects are due to the pro- and antioxidant activities of HSLs and AHBs, respectively. In light of the results obtained, the HSL and AHB effects are to be considered as a novel mechanism of regulating the activities of cell effectors of natural innate immunity. In symbiotic and parasitic systems, the mechanism involves the bimodal pattern of the effects of HSLs and AHBs that vary depending on their structure and concentrations.     

Relationships among several species of the subfamily Gymnelinae (Zoarcidae) inferred from mitochondrial DNA sequence analysis

Nucleotide sequences of the mtDNA COI and cytochrome b genes were determined in Magadanichthys skopetsi, a member of the new monotypic genus Magadanichthys, endemic to the northern coast of the Sea of Okhotsk. Comparison of this species with other representatives of the subfamily Gymnelinae (family Zoarcidae) revealed high genetic similarity of M. skopetsi to Hadropareia middendorffii and considerable differences between these species and Gymnelopsis ochotensis.     

Molecular bases of immune complex pathology

The binding of antigens with antibodies forms immune complexes in the body. Usually these complexes are eliminated by the system of mononuclear phagocytes without development of pathological changes. This review highlights principal mechanisms responsible for safe removal of immune complexes in primates and humans. Special attention is given to diseases known as “immune complex diseases”, when antigen-antibody complexes induce inflammatory reactions. The review considers key experimental works that significantly contributed to current knowledge of etiology and pathogenesis of type III hypersensitivity. Some factors of the development of immune complex syndrome such as level of humoral immune response to antigen, isotype and affinity of forming antibodies, the amount of immune complexes, and the consequences of their interaction with the complement system and Fc-receptors are analyzed based on the molecular mechanisms involved. The review contains a retrospective analysis of the most significant scientific achievements in immune complex pathology investigation within the last 100 years.     

Role of α-fetoprotein in differentiation of regulatory T lymphocytes

The effect of native α-fetoprotein (AFP) on the expression of T-regulatory lymphocyte (Treg) markers by activated CD4⁺ lymphocytes with different proliferative status was studied. α-Fetoprotein did not affect the ratio of proliferating and non-proliferating activated CD4⁺ cells. In the study of Treg differentiation, it was found that AFP at concentrations of 50 and 100 μg/mL significantly inhibited the number of nonproliferating CD4⁺FOXP3⁺ and CD4⁺FOXP3⁺HELIOS⁺ lymphocytes without affecting the expression of Treg markers by proliferating CD4⁺ lymphocytes.