Exposure to environmental radionuclides is associated with altered metabolic and immunity pathways in a wild rodent

Wildlife inhabiting environments contaminated by radionuclides face putative detrimental effects of exposure to ionizing radiation, with biomarkers such as an increase in DNA damage and/or oxidative stress commonly associated with radiation exposure. To examine the effects of exposure to radiation on gene expression in wildlife, we conducted a de novo RNA sequencing study of liver and spleen tissues from a rodent, the bank vole Myodes glareolus. Bank voles were collected from the Chernobyl Exclusion Zone (CEZ), where animals were exposed to elevated levels of radionuclides, and from uncontaminated areas near Kyiv, Ukraine. Counter to expectations, we did not observe a strong DNA damage response in animals exposed to radionuclides, although some signs of oxidative stress were identified. Rather, exposure to environmental radionuclides was associated with upregulation of genes involved in lipid metabolism and fatty acid oxidation in the livers – an apparent shift in energy metabolism. Moreover, using stable isotope analysis, we identified that fur from bank voles inhabiting the CEZ had enriched isotope values of nitrogen: such an increase is consistent with increased fatty acid metabolism, but also could arise from a difference in diet or habitat between the CEZ and elsewhere. In livers and spleens, voles inhabiting the CEZ were characterized by immunosuppression, such as impaired antigen processing, and activation of leucocytes involved in inflammatory responses. In conclusion, exposure to low dose environmental radiation impacts pathways associated with immunity and lipid metabolism, potentially as a stress‐induced coping mechanism.     

Status of the reproductive system of bony fish from the Teterev River and the Kiev Reservoir 20 years after the Chernobyl accident

The status of the reproductive system is investigated in five species of Teleostei from the Teterev River and the Kiev Reservoir (Ukraine), descendants of F₄2–F₇ generations of fish exposed to radiation from the accident at the Chernobyl nuclear power plant. Twenty years after the accident, a wide range of morphofuinctional anomalies of this system is present in fish. The most significant of them are: asymmetry and anomalous morphology of gonads, proliferation of connective tissue—sterilization, mass destruction of follicular and sex cells of various developmental stages, and hermaphroditism. Among the investigated species, disturbances of reproductive glands were preset to the highest extent in pike Esox lucius and crucian carp Carassius carassius. In the series of investigated generations the maximum frequency of occurrence of gonad anomalies was noted in F₄ and F₅, due to prolonged mutagenesis (Dubinin, 1986).     

异源精子在银鲫雌核发育子代中的生物学效应

黑龙江省方正县双凤水库的两性型银鲫群体是三倍体雌核发育种群。异源精子不仅能刺激银鲫卵雌核发育,而且还能影响雌核发育子代的某些性状,如对于子代的生长、性比、体色和肝脏LDH同工酶等都产生了影响。为区别于原有术语“雌核发育gynogenesis”,我们把这种表现了异源精子生物学效应的雌核发育称之为“异精雌核发育allogynogenesis”,发育的子代称之为“异育银鲫”。异育银鲫已以其明显的生长优势在生产上显示了优良的经济性状。       

三种鲫鱼品系同工酶比较研究

采用聚丙烯酰胺凝胶垂直板电泳技术,对彭泽鲫、银鲫D系以及野鲫三种鲫鱼品系的心、肝和肾脏组织的乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)、苹果酸酶(ME)、酯酶(EST)和超氧化物歧化酶(SOD)同工酶表型进行了比较研究.结果表明彭泽鲫乳酸脱氢酶同工酶比银鲫D系在肝组织多出二条酶带(LDH7'和LDH8');超氧化物歧化酶在心和肾组织中分别多出一条酶带(SOD12'),表明彭泽鲫和银鲫已在生化水平产生明显的分化,推测它们可能起源于不同的地区,由不同的祖先,独立演化而形成.此外,彭泽鲫和银鲫D系的同工酶电泳图谱都包含野鲫的基本酶带,而彭泽鲫和野鲫的酯酶同工酶电泳图谱尤为相似,推测彭泽鲫和银鲫可能起源于野鲫,而彭泽鲫和野鲫的关系较近,银鲫和野鲫的关系较远.     

Composition of leucocytes of the head kidney of the crucian carp (<Emphasis Type="Italic">Carassius auratus gibelio</Emphasis>, Cypriniformes: Cyprinidae) as affected by invasion of cestode <Emphasis Type="Italic">Digramma interrupta</Emphasis> (Cestoda; Pseudophyllidea)

The composition of leucocytes of the head kidney is studied in the crucian carps (Carassius auratus) either contaminated or uncontaminated with Digramma interrupta. The composition of leucocytes in the pronephros of the crucian carp from Lake Baikal basin has a lymphoid character. Compared to the crucian carp from the European part of Russia, in the fish from Baikal the granulocytopoetic processes are more pronounced. This is proved by the high content of young forms of granulocytes. In the fish infected with digramma, the immune suppression of proliferation of blasts and young forms of eosinophils was revealed. On the other hand, the inflammatory and humoral specific immune reactions are enhanced. Partial suppression of the immune response of C. auratus to invasion by D. interrupta facilitates development of the parasite.     

Studies on the Developmental Potentiality of Cultured Cell Nuclei of Fish

By means of the serial nuclear transplantation technique, the authors obtained a nuclear transplant fish from subcultured cell originated from the blastula cells of the crucian carp (Carassius auratus Linnaeus). This nuclear transplant fish survived for three years, but its sexual glands were undifferentiated. The authors have also obtained a sexually mature adult fish from short-term cultured kidney cell nucleus of an adult crucian carp.Results of the experiment implied that the subcultured cell nuclei of fish blastula cells and the specialized somatic cell nuclei of adult fish still retained their developmental totipotency, and thus, it indicated that there is a possibility of fish somatic cell breeding through the use of nuclear transplantation.     

Revision of the species composition of the wood mice from the genus Sylvaemus from the territory of Rostov oblast using karyological, allozyme and molecular genetic analysis

Using karyological, allozyme, and molecular genetic analysis, habitation of the four Sylvaemus wood mice species, pygmy wood mouse (S. uralensis), wood mouse (S. sylvaticus), yellow-necked mouse (S. flavicollis), and yellow-bellied mouse (S. fulvipectus) in Rostov oblast was demonstrated. Sylvaemus uralensis was distributed nearly over nearlythe whole territory of the oblast; S. sylvaticus was found in the central and western parts of the oblast on the right bank area of Don River; S. flavicollis inhabited northern and central parts of the right bank area of Don River; S. fulvipectus was found in the southern parts of the oblast, in the left bank area of Don River. Using the chromosome C-banding technique, it was demonstrated that the pygmy wood mice living in Rostov oblast in the right bank areas of Manych River and Don River in its low course, belonged to the eastern European chromosomal form of S. uralensis. The mice from the outskirts of the town of Salsk, the left bank area of Manych River, were probably hybrids between eastern European and southern European chromosomal forms. Based on the mitochondrial DNA cytochrome b gene fragment sequencing and chromosome C-banding, it was suggested that the wood mice inhabiting Rostov oblast belonged to the southern lineage of S. sylvaticus, living on Apennine Peninsula, Balkan Peninsula, and nearly throughout Ukraine.     

Difference in the hypoxia tolerance of the round crucian carp and largemouth bass: implications for physiological refugia in the macrophyte zone

The hypoxia tolerance of larval and juvenile round crucian carp, Carassius auratus grandoculis, and largemouth bass, Micropterus salmoides, was determined using respirometry to examine the potential of hypoxic areas in the macrophyte zone as physiological refugia for round crucian carp. The tolerance, which was measured as the critical oxygen concentration (Pc), was 1.32 mg O₂/l in the round crucian carp and 1.93 mg O₂/l in the largemouth bass. As the round crucian carp tolerated hypoxia better than the largemouth bass, hypoxic areas in the macrophyte zone might function as physiological refugia for round crucian carp.     

Population of silver crucian carp <Emphasis Type="Italic">Carassius auratus</Emphasis> (Cypriniformes,Cyprinidae) with “golden” individuals in the pond of the city of Volgograd

In the pond Gornaya Polyana of the city of Volgograd, the population of silver crucian carp Carassius auratus, some individuals of which have coloration similar to that of goldfish, were found. The studied “golden” individuals from this population morphologically do not differ from individuals of the same size from other populations of C. auratus that consist of typically colored individuals. Nevertheless, the total sample of C. auratus from Gornaya Polyana differs from samples of other populations of Volgograd oblast, besides the presence in it of “golden” individuals also, on average, in larger scales. The assumption is made that the population of C. auratus from Gornaya Polyana pond initially represented a naturalized goldfish. After mass dispersal of the Eurasian silver crucian carp C. auratus in the basin of the Lower Volga, hybridization between these two forms likely occurred. It is suggested that, over the territory of the former Soviet Union, several other populations of C. auratus that originated from the goldfish or have an admixture of its genes existed and exist.     

Polymorphism of the mtDNA control region in wild reindeer Rangifer tarandus (Mammalia: Artioodactyla) from the European part of Russia

Genetic diversity of wild reindeer (Rangifer tarandus) inhabiting the European part of Russia, including Komi Republic, Arkhangelsk oblast, Murmansk oblast, and the Republic of Karelia was characterized using sequence polymorphism of the mtDNA control region. Despite of currently low population number of wild reindeer, they were characterized by a high level of genetic diversity (?? = 0.018; H = 0.872 to 0.914). Phylogenetic analysis showed close relationships between European reindeer and wild reindeer of Siberia. In reindeer from Murmansk oblast a haplotype in common with the wild reindeer form Southwestern Norway was described. The reindeer sample examined contained no haplotypes earlier described for the reindeer of Central Norway. It is suggested that in recent past wild reindeer from the European north of Russia formed one population with the reindeer from the north of the Asian part of Eurasia.     

Intraspecific Scaling of the Resting and Maximum Metabolic Rates of the Crucian Carp (Carassius auratus)

The question of how the scaling of metabolic rate with body mass (M) is achieved in animals is unresolved. Here, we tested the cell metabolism hypothesis and the organ size hypothesis by assessing the mass scaling of the resting metabolic rate (RMR), maximum metabolic rate (MMR), erythrocyte size, and the masses of metabolically active organs in the crucian carp (Carassius auratus). The M of the crucian carp ranged from 4.5 to 323.9 g, representing an approximately 72-fold difference. The RMR and MMR increased with M according to the allometric equations RMR = 0.212M ^0.776 and MMR = 0.753M ^0.785. The scaling exponents for RMR (b _r) and MMR (b _m) obtained in crucian carp were close to each other. Thus, the factorial aerobic scope remained almost constant with increasing M. Although erythrocyte size was negatively correlated with both mass-specific RMR and absolute RMR adjusted to M, it and all other hematological parameters showed no significant relationship with M. These data demonstrate that the cell metabolism hypothesis does not describe metabolic scaling in the crucian carp, suggesting that erythrocyte size may not represent the general size of other cell types in this fish and the metabolic activity of cells may decrease as fish grows. The mass scaling exponents of active organs was lower than 1 while that of inactive organs was greater than 1, which suggests that the mass scaling of the RMR can be partly due to variance in the proportion of active/inactive organs in crucian carp. Furthermore, our results provide additional evidence supporting the correlation between locomotor capacity and metabolic scaling.     

In situ management options to improve crucian carp (Carassius carassius,L.) and brown trout (Salmo trutta,L.) population status in Central Europe: A case study from the Czech Republic

The crucian carp (Carassius carassius, L.) and the brown trout (Salmo trutta, L.) are vanishing from freshwater ecosystems of central Europe. To conserve both species, tailor‐made conservation management of habitats and populations of both species was implemented and tested in the Czech Republic (central Europe). This management was adjusted to reflect the ecological needs of both species. This study aimed to describe the results of a tested in situ management and to analyze the population growth of brown trout and crucian carp under ideal conditions. An experiment was performed at 14 small gravel pit lakes. Seven of them were adjusted to fit the crucian carp habitat requirements while the other seven were treated as a control group. The same experiment was done on 14 smaller streams and with brown trout. The occurrence and growth of crucian carp and brown trout were surveyed over 2 years. A significantly faster growth of both crucian carp and brown trout was observed on the adjusted lakes and streams in comparison to the control group ones. Trout and carp prospered on small streams and gravel pit lakes (respectively) that were free of angling, fish stocking, pollution, piscivorous predators, and competition with hybridizing species like Prussian carp (Carassius auratus, L.) or hatchery‐reared brown trout.     

Assessment of Possible Causes of Changes in Аbundance and Sexual Structure in Populations of Prussian Carp (<Emphasis Type="Italic">Carassius auratus gibelio</Emphasis> Bloch., 1783)

The prevalence of processes of the increase in abundance and changes in the sexual structure of Prussian carp populations in waterbodies differing dramatically in ecological properties and distant from each other (Lake Sevan and Rybinsk Reservoir) indicates the presence of global factors affecting climatic zones. The increase in environmental temperature due to global warming may be such a factor. Experimentally proven high thermophilicity and the thermal stability of Prussian carp, as well as its low sensitivity to hypoxia, provide some advantages for this species over many other fish inhabiting the same waterbodies.     

异源四倍体鲫鲤、三倍体湘云鲫和它们父母本线粒体DNA 12S rRNA基因遗传变异的分析

采用质粒克隆测序方法,获得了异源四倍体鲫鲤5个个体、异源四倍体鲫鲤雌核发育二倍体后代2个个体、三倍体湘云鲫2个个体及红鲫、湘江野鲤和日本白鲫各1个个体的线粒体DNA 12S rRNA基因的全序列。经对比发现,异源四倍体5个个体共享2种单元型,异源四倍体鲫鲤雌核发育二倍体后代2个个体、三倍体湘云鲫2个个体以及红鲫、湘江野鲤和日本白鲫各1个个体分别共享1种单元型。用MEGA 1.0 软件分析了它们的碱基组成和核苷酸序列差异,用邻接法构建系统进化树。它们间的序列同源性在95%~99%之间,异源四倍体鲫鲤、三倍体湘云鲫和它们母本（分别为红鲫和日本白鲫）之间的序列同源性大于异源四倍体鲫鲤、三倍体湘云鲫和它们父本（分别为湘江野鲤和异源四倍体鲫鲤）之间的序列同源性,结果表明：异源四倍体鲫鲤和三倍体湘云鲫在线粒体DNA 12S rRNA基因上具有母性遗传特征。本研究另一值得注意地方的是异源四倍体鲫鲤经过9代(F3-F11)繁殖后,在5个个体中发现了2种单元型,说明在四倍体基因库中存在遗传多样性,为四倍体基因库的繁殖、保护和种群复壮提供了一些有价值的信息。     

Effect of chronic irradiation on plant resistance to biotic stress in 30-km chernobyl nuclear power plant exclusion zone

It was established in greenhouse experiments that infection with powdery moldew (Erysiphe graminis DC. f. sp. tritici Em. Marchal) and brown rust (Puccinia triticana Erikss. & Henn.) of three wheat (Triticum aestivum L.) cultivars (Mironovskaya 808, Polesskay 70, and Kiyanka) grown from seeds, collected in the Chernobyl exclusion zone, was 1.5–2.0 times higher than of plants grown from control seeds. On field trials in the Chernobyl zone, wheat plant resistance to biotic stress was reduced. At artificial infection with brown rust, the disease development was enhanced on plots with increased radiation background. One of the mechanisms of the declined phytoimmunity potential under the action of low doses of chronic irradiation is evidently a reduced activity of plant proteinase inhibitors. Thus, in wheat and rye (Secale cereale L., cv. Saratovskaya) grains, their activity reduced by 35–60% as compared to control. Active form and race formation in the population of the cereal stem rust causal agent (Puccinia graminis Pers.) was observed in the Chernobyl zone. A “new” population of this fungus with high frequency of more virulent clones than in other Ukraine regions was distinguished. The results obtained independently in greenhouse and field trials performed in the Chernobyl zone demonstrated radiation stress influence on the pathogen-plant interactions. They indicate a necessity of monitoring the microevolutionary processes occurring in both plants and their pathogens under conditions of technogenic stresses.     

Expansion of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) to European Russia and adjacent regions

An invasive alien species, the harlequin ladybird Harmonia axyridis (Pallas, 1773), has quickly expanded its distribution in Eastern Europe. Records of H. axyridis from 31 localities in Lithuania, Latvia, the Ukraine, European Russia, and the Northern Caucasus are summarized and mapped. Within the last few years this species has established in south Latvia, on the Baltic Sea shore (Kaliningrad oblast and Lithuania), in the western and central Ukraine, Crimea, and in the Northern Caucasus. Besides that, individual specimens have been found in 4 more localities in European Russia. The species is recorded from Lipetsk oblast (European Russia), Crimea, and Nikolaev oblast (the Ukraine) for the first time.     

Isolation and characterization of microsatellite markers from Fangzheng silver crucian carp,Carassius auratus gibelio (Bloch), and cross‐amplification in the closely related species crucian carp,Carassius auratus auratus (Linnaeus)

We report the development of 20 microsatellite markers for Fangzheng silver crucian carp, Carassius auratus gibelio (Bloch). Nineteen out of 20 showed polymorphism with alleles ranging from two to 14. These loci were screened to amplify the closely related species crucian carp, Carassius auratus auratus (Linnaeus) and all of them can amplify DNA with the size similar to the former. The origin of silver crucian carp is in issue and the population genetic structure is still unclear. Microsatellite markers isolated from the silver crucian carp and their utility in the crucian carp will be useful for these researches.     

Revision of the species composition of the wood mice from the genus <Emphasis Type="Italic">Sylvaemus</Emphasis> from the territory of Rostov oblast using karyological,allozyme and molecular genetic analysis

Using karyological, allozyme, and molecular genetic analysis, habitation of the four Sylvaemus wood mice species, pygmy wood mouse (S. uralensis), wood mouse (S. sylvaticus), yellow-necked mouse (S. flavicollis), and yellow-bellied mouse (S. fulvipectus) in Rostov oblast was demonstrated. Sylvaemus uralensis was distributed nearly over the whole territory of the oblast; S. sylvaticus was found in the central and western parts of the oblast on the right bank area of Don River; S. flavicollis inhabited northern and central parts of Rostov oblast on the right bank area of Don River; S. fulvipectus was found in the southern parts of the oblast, in the left bank area of Don River. Using the chromosome C-banding technique, it was demonstrated that the pygmy wood mice living in Rostov oblast in the right bank areas of Manych River and Don River in its low course, belonged to the eastern European chromosomal form of S. uralensis. The pygmy wood mice from the outskirts of the town of Salsk, the left bank area of Manych River, were probably hybrids between eastern European and southern European chromosomal forms. Based on the mitochondrial DNA cytochrome b gene fragment sequencing and chromosome C-banding, it was suggested that the wood mice inhabiting Rostov oblast belonged to the southern lineage of S. sylvaticus, living on Apennine Peninsula, Balkan Peninsula, and nearly throughout Ukraine.     

Comparative and Evolutionary Analysis of the Cytochrome b Sequences in Cyprinids with Different Ploidy Levels Derived from Crosses

The mitochondrial cyt b genes in the allotetraploid and triploid crucian carp as well as triploid common carp were isolated and completely sequenced. Their DNA sequences were compared with those derived from the cyt b genes of the red crucian carp, Japanese crucian carp, and common carp with MEGA 1.0 software. Phylogenetic analysis revealed the sister relationships between allotetraploid and diploid red crucian carp, between the triploid crucian carp and diploid Japanese crucian carp, and between triploid common carp and diploid common carp. Our results indicated the cyt b genes in the allotetraploid, triploid crucian carp, and triploid common carp were maternally inherited. Through maternal inheritance, the cyt b gene in the F11 tetraploid displayed extremely high similarity to that in the female parent red crucian carp after 11 generations (from F1 to F11 hybrids). Since the establishment of the new tetraploid stocks has great significance in analyzing evolutionary theory of vertebrate and in improving aquaculture industry, analysis of the cyt b gene and the elucidation of the variation of the cyt b gene DNA in different cyprinids prove that cyt b is a useful genetic marker to monitor the variations in the progeny of the crosses.