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The Carpathian Mountains are one of the most complex orogenetic areas of Europe, with unique fauna, including the brown trout (Salmo trutta). In this study we performed population genetic analysis of 12 different S. trutta populations using two types of molecular markers: nine microsatellites and mitochondrial D-loop sequences. The following working hypothesis was considered: the Romanian Carpathians and their surrounding lowlands can be key relief units based on which the S. trutta genetic diversity, spread, distribution, connectivity, relative isolation and genetic divergence can be at least partially explained. The phylogenetic analysis revealed that the majority of sequences were grouped in the Danubian clade. The high haplotype diversity of the 12 analyzed brown trout populations can be explained by the high nucleotide diversity. The microsatellite analysis revealed an inbreeding event for all the loci and for the populations analyzed. The Romanian Carpathians' shape and geographic orientation play a zoogeographical key role driving force in respect to the S. trutta populations.

DNA barcoding is a molecular technique frequently used either for biodiversity monitoring and fish conservation or in the identification of the species of origin for raw and processed food from restaurants or fish markets. The most important aspect of this technique is that it works for all stages of life and can be used to distinguish between closely related taxa. Also, the technique has been used to unmask attempts of frauds in fish markets where more desirable and expensive fish are sometimes substituted with lower valued species. Our study aims to test the utility of the COI barcoding gene in the correct identification of several economically and ecologically valuable fish species, and interspecies hybrids, from Romanian wild fauna, aquaculture and fish markets. By combining the 122 COI sequences generated here with additional barcodes downloaded from GenBank and BOLD we screened several members of Acipenseriformes and Salmoniformes. While COI was able to correctly classify the majority of Salmoniformes, the identification process for Acipenseriformes proved more difficult, especially in the case of hybrids. Although the results show that DNA barcodes present a low degree of interspecies variation making classification possible only at the genus level, this technique is still relatively cheap, fast, and useful in the identification of incorrectly labelled market products.

The scope of this study is to investigate the expression of dmrt1, foxl2, ar, star and sox9 genes in the context of the gonad development stage of 21 month‐old Best Beluga individuals. No significant difference was observed between males and females but the cyp17a1 gene showed higher expression in male than in female gonads. The results suggest that during sampling the females were in perinucleolar stage and the males in early spermatogenesis stage which led to specific patterns of expression for the investigated genes. [ABSTRACT FROM AUTHOR]

Huchen or Danube salmon (Hucho hucho, Linnaeus, 1758) is an economically and ecologically valuable salmonid species, among the most endangered fish species inhabiting the Danube basin. Consequently, appropriate conservation measures are required to prevent the species extinction. Although H. hucho is a poorly studied species, there are several studies on other salmonid species regarding fast growth markers. Following these studies, the main purpose of the current study was to determine growth-related SNPs in myostatin gene in H. hucho. Therefore, we analysed 20 aquaculture individuals of same age separated in two groups according length and weight, by sequencing the amplification product of SaMSTNb23 and SaMSTNb33 primers pairs. We also statistically analysed the differences in the development of individuals over time regarding total length, weight and head length. Significantly variations were observed (p < 0.001) for the measured traits in both groups. Regarding the genetic analysis, we observed nine SNPs in the mstn gene structure. Considering these results, it appears that the analysed markers are not appropriate for genetic analysis of growth traits in H. hucho. To extend gene expression pattern analysis, other markers are recommended for further evaluation. [ABSTRACT FROM AUTHOR]

The Acipenseridae family includes sturgeon species that have the ability to easily generate interspecies hybrids in both natural and aquaculture conditions. For the differentiation between hybrids and pure species, mitochondrial markers have been used, but they have not proven effective. Nuclear markers, such as the RP1S7 marker, encoding the S7 ribosomal protein, show to be more effective in achieving this differentiation. The purpose of this study was to evaluate the capacity of this nuclear marker in discriminating between pure sturgeon species and their interspecies hybrids. DNA samples were isolated from fin fragments. The RP1S7 marker was amplified by PCR and the obtained amplicons were analysed by agarose gel electrophoresis and sequencing. In order to determine the accuracy of the primers and to validate this marker, the sequences were compared with similar ones from GenBank. The resulting electrophoretic profiles showed differences that can be used to distinguish between pure sturgeon species and their interspecies hybrids. Therefore, the RP1S7 marker can be included in a panel of DNA markers for molecular identification of sturgeon species and their hybrids. [ABSTRACT FROM AUTHOR]

Sturgeons are highly valuable species from both a conservation and economic point of view. Their very sought-after caviar extracted from mature females has both a rich culture around it and opens the way for interesting research. Because of the advanced age at which females and males could be identified in aquaculture it is important to develop a set of molecular markers that could make the distinction easy. For this, a better understanding of the sexual development of sturgeons is necessary. We selected the Dmrt1 (doublesex and mab-3 related transcription factor 1) and the Cyp17a1 (17α-hydroxylase) markers with the scope of investigating the gonad development of sturgeon individuals. Both markers appear to be expressed in the gonad but no statistically significant difference in expression is observed between females and males. This could mean that the markers are equally involved in female and male sexual development at the stage of sampling. This study paves the way for a better understanding of sturgeon sexual development. [ABSTRACT FROM AUTHOR]

The Salmonidae fish family is well represented in Romanian fauna, with a total of six species in the wild and reared in fish farms. Among them, the brown trout (Salmo trutta fario) can be found in all major Romanian river basins. However, anthropogenic activities might disrupt salmonids' habitats, so that inbreeding and genetic isolation might easily occur in the wild populations. We analyzed two wild brown trout populations from rivers targeted by anthropogenic activities, by using nuclear markers and genotyping in order to observe their genetic structure. We analyzed nine microsatellites and we observed their alleles frequencies, number of private alleles, observed and expected heterozygosity, as well as their population structure. The two populations are not in Hardy-Weinberg equilibrium for most of the loci and the inbreeding coefficient for both populations suggests a heterozygote deficit. Further sequencing data are needed in order to have a better view upon their complete genetic structure [ABSTRACT FROM AUTHOR]

The Danube salmon or huchen (Hucho hucho, Linnaeus, 1758) is an endemic species in the Danube basin, being almost extinct in particular because of anthropogenic activities. The huchen has a special status throughout Europe, being listed on Appendix III of the Bern Convention and on Annexes II and V of the EU Habitat Directive and is a protected species in Romania. Molecular methods that use nuclear and mitochondrial DNA markers are recommended in order to contribute for a better management of aquaculture activities and also to improve the measures for conservation of endangered species such huchen. Our study aims to evaluate several DNA-based methods for species identification of Hucho hucho from the wild and aquaculture. We proposed two methods focused on the mitochondrial genome (DNA barcoding and PCR-RFLP), and one on the nuclear markers (genotyping). Methods that analyse the mitochondrial genome are focused on the COI gene and D-loop/Cytb regions, while those that analyse nuclear markers are focused on microsatellites. All three methods were tested on 10 huchen individuals from wild and aquaculture. Therefore, techniques such as PCR-RFLP, sequencing and genotyping gave results that were easily interpretable and could be recommended as powerful species detection methods with applicability in aquaculture and for restocking purposes. [ABSTRACT FROM AUTHOR]

DNA barcoding aims to be an effective tool for species identification based on partial sequence of the mitochondrial cytochrome c oxidase 1 gene (CO I). The method offers several advantages like small amount of biological samples needed, applicability for all life stages and differentiation among phenotypically alike species. Our study aimed at barcoding economically and ecologically important salmonids. The sequences were determined by using specific primers when the so-call universal primers failed to give amplifications. The sequences were BLAST with GenBank and BOLD databases for species identity confirmation. With one exception, the results of barcoding were congruent with the ones based on morphology in the cases when this last type of diagnostic was done. The method can be regular carried out for species identification, but is totally inefficient when is dealing with hybrids and should be avoided for species that can naturally hybridize. [ABSTRACT FROM AUTHOR]

Salmonids are members of the Salmonidae family which includes the subfamily Coregoninae, subfamily Thymallinae and subfamily Salmoninae. This family includes fish of interest for aquaculture and sport fishing. The salmonids from the natural environment on Romanian territory are Salmo trutta fario, Salmo labrax, Salvelinus fontinalis fontinalis, Hucho hucho, and Thymallus thymallus. Gene flow from fishery populations to those in the natural habitat may create substantial problems to natural species which leads to a reduction of inherited genetic diversity and of environment adjustment due to a loss of natural capacity to adapt. Due their characteristics, microsatellites prove themselves usefull in population genetics studies. Aim of our study is to evaluate the genetic diversity of two populations of brown trout from Făgăraş Mountains using nuclear markers. For this purpose we analyzed the polymorphism of nine microsatellite loci (BS131, Str60, Str73, Str15, Str543, OmyFGT, Ssa85, Ssa197, Strutta12) in two brown trout population from Făgăraş Mountains. We successfully amplified all microsatellite loci obtaining allele peaks of different sizes. The number of allele ranged beetwen 1 (Str73) and 26 (OmyFGT). The analyzed trout populations show a relatively high degree of genetic diversity, being also characterized by a low level of inbreeding among individuals. This technology has great potential for investigating the genetic diversity of the wild population and, also, might be extended to aquaculture studies. [ABSTRACT FROM AUTHOR]

Salmonids are a heterogeneous group of fish classified in one family - Salmonidae. These species are natives of the northern hemisphere, but currently have been introduced in many countries all over the world for sport fishing and aquaculture. Despite the considerable importance of salmonids, their evolutive history is still a controversial issue. The aim of the current study is to infer the phylogeny within the Salmonidae family using as phylogenetic marker the D-loop region. For this purpose, an PCR amplification of D-loop region, followed by direct sequencing and phylogenetic analysis have been performed in four salmonids species from Romanian fauna - Salmo trutta fario, Salvelinus fontinalis, Thymallus thymallus and Oncorhynchus mykiss. For a more accurate phylogenetic classification of these species within Salmonidae family the analysis included similar sequences from GenBank belonging to 17 salmonid species and an osmerid species used as outgroup. The the phylogenetic trees illustrating the evolutive relationships within Salmonidae were constructed by using Neighbor Joining and Maximum Parsimony methodologies implemented in MEGA5.The phylogenetic analysis using mitochondrial control region as marker has allowed an overview about the positions occupied by Romanian salmonids within the Salmonidae family. [ABSTRACT FROM AUTHOR]

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Sturgeons, a class of fish with a particular scientific and commercial importance have been overexploited through overfishing and poaching, nowadays being at the brink of extinction. The developments of the molecular techniques allow the detection of intraspecific genetic differences and could ensure an increased ability to characterize the extent of genetic variation in sturgeon populations, both aquaculture and wildlife. In our study we optimized a protocol for microsatellites amplification in Siberian sturgeon, Acipenser baerii. The microsatellite markers were originally designed for the American lake sturgeon, Acipenser fulvescens, Adriatic sturgeon, Acipenser naccari and Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus. We successfully amplified five microsatellite loci (LS 19, LS 68, Aox 9, Aox 45, AnacE4) obtaining allele peaks of different sizes which were analyzed by capilary electrophoresis. Except the locus AnacE4 that presented a low polymorphism, the other four loci were displaying minimum 6 alleles for each locus. Therefore, caracterization of these new markers increase the panel of molecular tools available for fish farmers to monitoring levels of genetic variation within stocks. [ABSTRACT FROM AUTHOR]

The preparation of hybrid transition metalloproteins by thiol-selective incorporation of organometallic rhodium- and ruthenium complexes is described. Phosphine ligands and two rhodium-diphosphine complexes bearing a carboxylic acid group were coupled to the cysteine of PYP R52G, yielding a metalloenzyme active in the rhodium catalyzed hydrogenation of dimethyl itaconate. The successful coupling was shown by 31P NMR spectroscopy and ESI mass spectroscopy. In addition wild-type PYP (PYP WT), PYP R52G and ALBP were successfully modified with a (η6-arene) ruthenium(ii) phenanthroline complex viaa maleimide linker. [ABSTRACT FROM AUTHOR]