Species-specific Features Research Articles

-Reproductive strategies of two common sympatric Mediterranean sponges: Dysidea avara (Dictyoceratida) and Phorbas tenacior (Poecilosclerida).

Despite their abundance in benthic ecosystems, life cycles and reproductive features of most sponge species remain unknown. We have studied the main reproductive features of two demosponges, Dysidea avara and Phorbas tenacior, belonging to phylogenetically distant groups: Orders Dictyoceratida and Poecilosclerida, respectively. Both sponges are abundant and share habitat in the Mediterranean rocky sublittoral. They brood parenchymella larvae with different morphology and behaviour. Sampling was conducted monthly over a two-year period in a locality where both species coexist. The two species reproduced in spring-summer, and presented species-specific reproductive features despite being subject to the same environmental conditions. D. avara has a shorter reproductive period than P. tenacior, ending before the peak of temperature in summer, while the reproductive period of P. tenacior lasts until beginning of autumn. Brooding larvae were present in June-July in D. avara, and in August-October in P. tenacior. Larval size, reproductive effort and number of larvae produced (measured the month with the maximum production) were significantly higher in D. avara than in P. tenacior. A higher reproductive effort and larval traits point to a more opportunistic life strategy in D. avara than in P. tenacior. A lack of overlap in the timing of larval release, as well as different reproductive traits, may reduce competition and facilitate the coexistence of these two sympatric and abundant sponges.

Chimeric Plasmodium falciparum parasites expressing Plasmodium vivax circumsporozoite protein fail to produce salivary gland sporozoites

BackgroundRodent malaria parasites where the gene encoding circumsporozoite protein (CSP) has been replaced with csp genes from the human malaria parasites, Plasmodium falciparum or Plasmodium vivax, are used as pre-clinical tools to evaluate CSP vaccines in vivo. These chimeric rodent parasites produce sporozoites in Anopheles stephensi mosquitoes that are capable of infecting rodent and human hepatocytes. The availability of chimeric P. falciparum parasites where the pfcsp gene has been replaced by the pvcsp would open up possibilities to test P. vivax CSP vaccines in small scale clinical trials using controlled human malaria infection studies.MethodsUsing CRISPR/Cas9 gene editing two chimeric P. falciparum parasites, were generated, where the pfcsp gene has been replaced by either one of the two major pvcsp alleles, VK210 or VK247. In addition, a P. falciparum parasite line that lacks CSP expression was also generated. These parasite lines have been analysed for sporozoite production in An. stephensi mosquitoes.ResultsThe two chimeric Pf-PvCSP lines exhibit normal asexual and sexual blood stage development in vitro and produce sporozoite-containing oocysts in An. stephensi mosquitoes. Expression of the corresponding PvCSP was confirmed in oocyst-derived Pf-PvCSP sporozoites. However, most oocysts degenerate before sporozoite formation and sporozoites were not found in either the mosquito haemocoel or salivary glands. Unlike the chimeric Pf-PvCSP parasites, oocysts of P. falciparum parasites lacking CSP expression do not produce sporozoites.ConclusionsChimeric P. falciparum parasites expressing P. vivax circumsporozoite protein fail to produce salivary gland sporozoites. Combined, these studies show that while PvCSP can partially complement the function of PfCSP, species-specific features of CSP govern full sporozoite maturation and development in the two human malaria parasites.

Genome-wide survey, characterization, and expression analysis of RING finger protein genes in Brassica oleracea and their syntenic comparison to Brassica rapa and Arabidopsis thaliana.

The ubiquitin-mediated post-translational regulatory pathway regulates a broad range of cell functions in all eukaryotes. It requires the involvement of a large number of E3 ligases, of which more than one third belongs to the RING protein family as in Arabidopsis thaliana. In this study, a total of 756 RING domains in 734 predicted proteins were identified in Brassica oleracea. Their encoding genes were characterized by RING domain type, additional domain, and expression pattern, and mapped on the nine chromosomes of B. oleracea. Comparison of these results with B. rapa and A. thaliana revealed some common as well as species-specific features. Our results showed that the differential gene loss following the whole genome triplication has largely contributed to the RING protein gene number variation among these species, although other factors such as tandem duplication, RING domain loss, or modification had also contributed to this variation. Analysis of RNA-seq data showed that these RING protein genes were functionally diversified and involved in all the stages of plant growth and development, and that the triplicated members were also diverged in expression with one member often more dominantly expressed over the two others in the majority of cases. Our study lays the foundation for further functional determination of each RING protein gene among species of the genus Brassica.

Генетична структура сазана амурського ТзОВ «Карпатський водограй»

The purpose. To study genetic structure of breed herd of Amur carp selected in «Karpatskyi vodohrai» Ltd. (Lviv oblast) with the use of different types of markers and to determine the level of somatic mutagenesis by the microkernel test. Methods. Laboratory researches, computer statistical analysis. Results. Genetic structure of Amur carp on separate types of molecular-genetic markers (DNA-markers, genetic-biochemical systems) is studied. Species-specific features of genetic structure on probed loci are determined. The level of actual and expected heterozygosity is calculated. Increased allele and genotypic variety of genetic structure can be caused by a little heightened intensity of the carried out selection work. The detected excess of heterozygotes on separate loci testifies to presence of stabilization processes of genetic structure. Research of the level of somatic mutagenesis is also carried out at use of micronucleus test. Conclusions. At use of different types of molecular-genetic markers the information on genetic structure of a carp and its variety on genome level is gained. These results testify to the following: genome preserved resistant gene complexes, despite of significant selection effort. The applied genetically-statistical approaches can be used for monitoring genetic structure of groups of a carp of Ukraine, determination of the level of consolidation and phylogenetic links between them with their subsequent genetic certification. Results of researches of the level of somatic mutagenesis at use of micronucleus test shown that the probed group of fishes was characterized by average level of erythrocytes with micronucleus MNE (4,7±0,3‰), low level of lymphocytes with micronucleus and binucleate lymphocytes which total has made 3,5±0,3‰ that in its turn testifies to satisfactory conditions of selection.

The Morphology of the Mandibles in Zoea I Larvae of the Burrowing Shrimp Genera Upogebia (Gebiidea) and Nihonotrypaea (Axiidea)

The mandibles in the first zoeal stage of five species of the burrowing shrimp genera Upogebia (infraorder Gebiidea) and Nihonotrypaea (infraorder Axiidea) have been examined by scanning electron microscopy. The general shape of the mandibles in Upogebia zoeae is similar to that in Anomura larvae; in Nihonotrypaea, it is intermediate between the mandibles of anomuran and caridean shrimp larvae. The asymmetry of the mandibles, which is more pronounced in Nihonotrypaea, is confirmed. Species-specific features of the structure of the incisor process are found in three Upogebia species, while two Nihonotrypaea species almost do not differ in the mandible structure in their zoea I larvae. The morphological features of the mandibles indicate differences in the diet of Upogebia and Nihonotrypaea larvae. Under natural conditions, zoea I of the studied Nihonotrypaea species may feed on diatoms, which should be taken into account when rearing these decapod larvae in the laboratory.

Transposable elements and gene expression during the evolution of amniotes

BackgroundTransposable elements (TEs) are primarily responsible for the DNA losses and gains in genome sequences that occur over time within and between species. TEs themselves evolve, with clade specific LTR/ERV, LINEs and SINEs responsible for the bulk of species-specific genomic features. Because TEs can contain regulatory motifs, they can be exapted as regulators of gene expression. While TE insertions can provide evolutionary novelty for the regulation of gene expression, their overall impact on the evolution of gene expression is unclear. Previous investigators have shown that tissue specific gene expression in amniotes is more similar across species than within species, supporting the existence of conserved developmental gene regulation. In order to understand how species-specific TE insertions might affect the evolution/conservation of gene expression, we have looked at the association of gene expression in six tissues with TE insertions in six representative amniote genomes.ResultsA novel bootstrapping approach has been used to minimise the conflation of effects of repeat types on gene expression. We compared the expression of orthologs containing recent TE insertions to orthologs that contained older TE insertions, and the expression of non-orthologs containing recent TE insertions to non-orthologs with older TE insertions. Both orthologs and non-orthologs showed significant differences in gene expression associated with TE insertions. TEs were found associated with species-specific changes in gene expression, and the magnitude and direction of expression changes were noteworthy. Overall, orthologs containing species-specific TEs were associated with lower gene expression, while in non-orthologs, non-species specific TEs were associated with higher gene expression. Exceptions were SINE elements in human and chicken, which had an opposite association with gene expression compared to other species.ConclusionsOur observed species-specific associations of TEs with gene expression support a role for TEs in speciation/response to selection by species. TEs do not exhibit consistent associations with gene expression and observed associations can vary depending on the age of TE insertions. Based on these observations, it would be prudent to refrain from extrapolating these and previously reported associations to distantly related species.

SPECIES- AND AGE-SPECIFIC CHARACTERISTICS OF THE LACTATE DEHYDROGENASE SYSTEM IN TISSUES OF RODENTS (MAMMALIA: RODENTIA)

The aim of this study was to analyze the species-specific features and age-related changes in the total lactate dehydrogenase activity (LDh, EC 1.1.1.27) and LDh patterns in some tissues in three species of rodents (Rodentia) with different ecological characteristics – the northern birch mouse Sicista betulina (Pallas, 1779), the European water vole Arvicola amphibius (L., 1758) and the tundra vole Microtus oeconomus (Pallas, 1776). Compared to the European water vole and the northern birch mouse, the tundra vole had a higher content of M-subunits and the amount of LDh-5 isoenzyme in the liver and skeletal muscles, higher contents of aerobic LDh-1 isoenzymes and, respectively, of h-subunits in kidneys and heart. In the heart and kidneys, the hybrid fractions (LDh-2, LDh-3, LDh-4) dominated over LDh-1 and LDh-5 in the northern birch mouse. The total LDh activity in the liver and kidneys of the northern birch mouse was higher than in the tundra vole. The extent of anaerobic ATP production in the liver of small rodents varied – the liver of the diving European water vole contained more LDh-2, LDh- 3, LDh-4 and h-subunits than the corresponding tissue in the non-diving tundra vole. In kidneys of the northern birch mouse and European water vole, the content of the LDh- 5 isoenzyme increased through the ontogeny. The LDh activity was higher in the heart of European water vole adults compared to young animals. Species-specific differences in LDh isoenzyme spectra and total LDh activity in the studied mammals reflect their adaptation to the semi-aquatic and hibernating lifestyles.

Anatomical features of cross-sections of the genus Equisetum members

The anatomical structure of cross-sections of internodes of stems and branches of 9 species and 5 interspecific hybrids of the subgenus Equisetum and Hippochaete ( Equisetum , Equisetaceae) was studied: E. arvense L., E. fluviatile L., E. palustre L., E. pratense Ehrh., E. sylvaticum L., E. × mildeanum Rothm. ( E. pratense × E. sylvaticum ), E. × sergijevskianum CN Page et Gureeva ( E. pratense × E. palustre ), E. × lofotense Lubienski ( E. arvense × E. sylvaticum ), E. hyemale L., E. ramosissimum Desf., E. scirpoides Michx, E. variegatum Schleich. ex F. Weber et D. Mohr., E. × moorei Newman ( E. hyemale × E. ramosissimum ), E. × trachyodon (A. Braun) W. D. J. Koch ( E. hyemale × E. variegatum ). The species-specific anatomical features of the species of the subgenus Equisetum are as follows: the shape of the ridge on the cross-section (in profile) and the presence of silica spines, the size of the vallecular cavities, the position and size of the mechanical tissue under the ridges. For species from the subgenus Hippochaete , the number of ridges and the shape of the ridge on the cross-section, the outline of the mechanical tissue, the presence of siliceous tubercles are important. For all species, the diagnostic feature is the size and position of the mechanical tissue in the cut, as well as the position and number of layers of the endoderm. The size of the central cavity cannot be used as a diagnostic feature. In this case, it is better to use the relative dimensions of the vallecular cavities to the central cavity. The article gives detailed descriptions of cross-sections.

The 4D Nucleome: Genome Compartmentalization in an Evolutionary Context.

4D nucleome research aims to understand the impact of nuclear organization in space and time on nuclear functions, such as gene expression patterns, chromatin replication, and the maintenance of genome integrity. In this review we describe evidence that the origin of 4D genome compartmentalization can be traced back to the prokaryotic world. In cell nuclei of animals and plants chromosomes occupy distinct territories, built up from ~1 Mb chromatin domains, which in turn are composed of smaller chromatin subdomains and also form larger chromatin domain clusters. Microscopic evidence for this higher order chromatin landscape was strengthened by chromosome conformation capture studies, in particular Hi-C. This approach demonstrated ~1 Mb sized, topologically associating domains in mammalian cell nuclei separated by boundaries. Mutations, which destroy boundaries, can result in developmental disorders and cancer. Nucleosomes appeared first as tetramers in the Archaea kingdom and later evolved to octamers built up each from two H2A, two H2B, two H3, and two H4 proteins. Notably, nucleosomes were lost during the evolution of the Dinoflagellata phylum. Dinoflagellate chromosomes remain condensed during the entire cell cycle, but their chromosome architecture differs radically from the architecture of other eukaryotes. In summary, the conservation of fundamental features of higher order chromatin arrangements throughout the evolution of metazoan animals suggests the existence of conserved, but still unknown mechanism(s) controlling this architecture. Notwithstanding this conservation, a comparison of metazoans and protists also demonstrates species-specific structural and functional features of nuclear organization.

PERSISTENT ORGANIC POLLUTANTS IN SEABIRDS FROM THE OKHOTSK SEA

Persistent organic pollutants as organochlorine pesticides are lipophilic anthropogenic substances. Isomers of HCH and DDT and their metabolites are detected in organs of the seabirds Larus schistisagus, Aethia cristatella, Aethia pusilla, Fulmarus glacialis, and Oceanodroma furcata collected in the Okhotsk Sea. Total content of the pesticides in the certain examined organs varies from 28 ng to 16095 ng per 1 g of lipids: 28–8289 ng/g in feathers, 1567–16095 ng/g in feathers with skin, 1679–2478 ng/g in liver, 2230–3000 ng/g in muscles. Their average content in the whole body changes in the range from 12.5 to 15112.0 ng/g. Species specific features of the lipophilic xenobiotics accumulation are conditioned mainly by feeding habits and lipid content in the organs.

Connecting infrared spectra with plant traits to identify species

Plant traits are used to define species, but also to evaluate the health status of forests, plantations and crops. Conventional methods of measuring plant traits (e.g. wet chemistry), although accurate, are inefficient and costly when applied over large areas or with intensive sampling. Spectroscopic methods, as used in the food industry and mineralogy, are nowadays applied to identify plant traits, however, most studies analysed visible to near infrared, while infrared spectra of longer wavelengths have been little used for identifying the spectral differences between plant species. This study measured the infrared spectra (1.4–16.0 µm) on individual, fresh leaves of 19 species (from herbaceous to woody species), as well as 14 leaf traits for each leaf. The results describe at which wavelengths in the infrared the leaves’ spectra can differentiate most effectively between these plant species. A Quadratic Discrimination Analysis (QDA) shows that using five bands in the SWIR or the LWIR is enough to accurately differentiate these species (Kappa: 0.93, 0.94 respectively), while the MWIR has a lower classification accuracy (Kappa: 0.84). This study also shows that in the infrared spectra of fresh leaves, the identified species-specific features are correlated with leaf traits as well as changes in their values. Spectral features in the SWIR (1.66, 1.89 and 2.00 µm) are common to all species and match the main features of pure cellulose and lignin spectra. The depth of these features varies with changes of cellulose and leaf water content and can be used to differentiate species in this region. In the MWIR and LWIR, the absorption spectra of leaves are formed by key species-specific traits including lignin, cellulose, water, nitrogen and leaf thickness. The connection found in this study between leaf traits, features and spectral signatures are novel tools to assist when identifying plant species by spectroscopy and remote sensing.

Cytogenetic characterization of three species of Antilochus (Hemiptera: Heteroptera: Pyrrhocoridae)

The study provides comparative account of karyological details of three species of Antilochus viz., A. lineatipes (Stal, 1858), A. russus Stal, 1863 and A. coquebertii (Fabricius, 1803) collected from northern parts of India using differential banding techniques. The chromosome complement of A. lineatipes is described for the first time. In A. lineatipes, thick and broad C bands are observed at terminal and interstitial regions of autosomes while in A. russus and A. coquebertii, thin C bands are observed only at termini of autosomes. X chromosome shows two terminal C bands in A. russus and one terminal and one interstitial in A. coquebertii. In A. lineatipes, X2 is intensely C positive. All the bands appear bright with both DAPI and CMA3. With silver staining, ten autosomes are intensely stained while three show very thin silver positive impregnations in both A. russus and A. coquebertii. DAPI/CMA3 bright heterochromatic bands on X overlap with silver bands. A comparative analysis of banding patterns in three species has yielded species-specific features which can be used as cytogenetic markers to differentiate these three congeneric species.

External and local controls on land-sea coupling assessed by stable isotopic signatures of mangrove producers in estuaries of Pacific Panama

Foliar stable isotopic signatures of nitrogen, carbon, and sulfur in mangrove vegetation from the Pacific coast of Panama were insensitive to inputs from watersheds with different area of forest land cover, and to seasonal, inter-annual, and global-scale-driven contrasts in rainfall and upwelling. N, C, and S content of mangrove vegetation were not affected by inputs from watersheds with different degrees of deforestation, but showed some influence of down-estuary transformations. While there was substantial variation that remained un-explained, isotopic signatures and nutrient contents were largely determined by species-specific features, and showed substantial small-scale variation reflecting local differences, within-estuary plant-sediment links. The ability of mangrove estuaries to erase effects of deforestation points out that conservation of these wetland ecosystems is important, because, at least in the sites we studied, transformations within mangrove estuaries were strong enough to protect water quality in receiving coastal waters.

The Role of Transposable Elements in Emergence of Metazoa.

Systems initially emerged for protecting genomes against insertions of transposable elements and represented by mechanisms of splicing regulation, RNA-interference, and epigenetic factors have played a key role in the evolution of animals. Many studies have shown inherited transpositions of mobile elements in embryogenesis and preservation of their activities in certain tissues of adult organisms. It was supposed that on the emergence of Metazoa the self-regulation mechanisms of transposons related with the gene networks controlling their activity could be involved in intercellular cell coordination in the cascade of successive divisions with differentiated gene expression for generation of tissues and organs. It was supposed that during evolution species-specific features of transposons in the genomes of eukaryotes could form the basis for creation of dynamically related complexes of systems for epigenetic regulation of gene expression. These complexes could be produced due to the influence of noncoding transposon-derived RNAs on DNA methylation, histone modifications, and processing of alternative splicing variants, whereas the mobile elements themselves could be directly involved in the regulation of gene expression in cis and in trans. Transposons are widely distributed in the genomes of eukaryotes; therefore, their activation can change the expression of specific genes. In turn, this can play an important role in cell differentiation during ontogenesis. It is supposed that transposons can form a species-specific pattern for control of gene expression, and that some variants of this pattern can be favorable for adaptation. The presented data indicate the possible influence of transposons in karyotype formation. It is supposed that transposon localization relative to one another and to protein-coding genes can influence the species-specific epigenetic regulation of ontogenesis.

Phenotypic and Functional Characteristics of Human Schwann Cells as Revealed by Cell-Based Assays and RNA-SEQ

This study comprehensively addresses the phenotype, function, and whole transcriptome of primary human and rodent Schwann cells (SCs) and highlights key species-specific features beyond the expected donor variability that account for the differential ability of human SCs to proliferate, differentiate, and interact with axons in vitro. Contrary to rat SCs, human SCs were insensitive to mitogenic factors other than neuregulin and presented phenotypic variants at various stages of differentiation, along with a mixture of proliferating and senescent cells, under optimal growth-promoting conditions. The responses of human SCs to cAMP-induced differentiation featured morphological changes and cell cycle exit without a concomitant increase in myelin-related proteins and lipids. Human SCs efficiently extended processes along those of other SCs (human or rat) but failed to do so when placed in co-culture with sensory neurons under conditions supportive of myelination. Indeed, axon contact-dependent human SC alignment, proliferation, and differentiation were not observed and could not be overcome by growth factor supplementation. Strikingly, RNA-seq data revealed that ~ 44 of the transcriptome contained differentially expressed genes in human and rat SCs. A bioinformatics approach further highlighted that representative SC-specific transcripts encoding myelin-related and axon growth-promoting proteins were significantly affected and that a deficient expression of key transducers of cAMP and adhesion signaling explained the fairly limited potential of human SCs to differentiate and respond to axonal cues. These results confirmed the significance of combining traditional bioassays and high-resolution genomics methods to characterize human SCs and identify genes predictive of cell function and therapeutic value.

Proteomic Profile of the Bacterium Sinorhizobium meliloti Depends on Its Life Form and Host Plant Species

The importance of root nodule bacteria in biotechnology is determined by their distinctive feature: symbiotic nitrogen fixation resulting in the production of organic nitrogen-containing compounds. While interacting with host legume plants, the cells of these bacteria undergo global changes at all levels of expression of genetic information leading to the formation in root nodules of so-called bacteroids functioning as nitrogen fixation factories. The molecular mechanisms underlying plant-microbial symbiosis are actively investigated, and one of the most interesting and poorly studied aspects of this problem is the species-specificity of interaction between root nodule bacteria and host plants. In this work we have performed the proteomic analysis of the Sinorhizobium meliloti bacteroids isolated from two legume species: alfalfa (Medicago sativa L.) and yellow sweet clover (Melilotus officinalis L.). It has been shown that the S. meliloti bacteroids produce a lot of proteins (many of them associated with symbiosis) in a host-specific manner, i.e., only in certain host plant species. It has been demonstrated for the first time that the levels of expression in bacteroids of the genes encoding the ExoZ and MscL proteins responsible for the synthesis of surface lipopolysaccha-rides and formation of a large conductance mechanosensitive channel, respectively, depend on a host plant species that confirms the results of proteomic analysis. Overall, our data show that the regulation of bacteroid development by the host plant has species-specific features.

The RFK catalytic cycle of the pathogen Streptococcus pneumoniae shows species-specific features in prokaryotic FMN synthesis

Emergence of multidrug-resistant bacteria forces us to explore new therapeutic strategies, and proteins involved in key metabolic pathways are promising anti-bacterial targets. Bifunctional flavin-adenine dinucleotide (FAD) synthetases (FADS) are prokaryotic enzymes that synthesise the flavin mononucleotide (FMN) and FAD cofactors. The FADS from the human pathogen Streptococcus pneumoniae (SpnFADS)–causative agent of pneumonia in humans − shows relevant catalytic dissimilarities compared to other FADSs. Here, by integrating thermodynamic and kinetic data, we present a global description of the riboflavin kinase activity of SpnFADS, as well as of the inhibition mechanisms regulating this activity. Our data shed light on biophysical determinants that modulate species-specific conformational changes leading to catalytically competent conformations, as well as binding rates and affinities of substrates versus products. This knowledge paves the way for the development of tools − that taking advantage of the regulatory dissimilarities during FMN biosynthesis in different species − might be used in the discovery of specific anti-pneumococcal drugs.

The factors affecting the evolution of the anthocyanin biosynthesis pathway genes in monocot and dicot plant species

BackgroundThe available data demonstrate that even in universal metabolic pathways, some species-specific regulatory features of structural genes are present. For instance, in the anthocyanin biosynthesis pathway (ABP), genes may be regulated by ABP-specific regulatory factors, and their expression levels may be strongly associated with anthocyanin pigmentation, or they may be expressed independently of pigmentation. A dataset of orthologous ABP genes (Chs, Chi, F3h, F3’h, Dfr, Ans) from monocot and dicot plant species that have distinct gene regulation patterns and different types of pollination was constructed to test whether these factors affect the evolution of the genes.ResultsUsing a maximum likelihood approach, we demonstrated that although the whole set of the ABP genes is under purifying selection, with greater selection acting on the upstream genes than on the downstream genes, genes from distinct groups of plant species experienced different strengths of selective pressure. The selective pressure on the genes was higher in dicots than in monocots (F3h and further downstream genes) and in pollinator-dependent plants than in pollinator-independent species (Chi and further downstream genes), suggesting an important role of pollination type in the evolution of the anthocyanin biosynthesis gene network. Contrasting effects of the regulation patterns on evolution were detected for the F3h and Dfr genes, with greater selective pressure on the F3h gene in plant species where the gene expression was not strongly associated with pigmentation and greater selective pressure on Dfr in plant species where the gene expression was associated with pigmentation.ConclusionsWe demonstrated the effects of pollination type and patterns of regulation on the evolution of the ABP genes, but the evolution of some of the genes could not be explained in the framework of these factors, such as the weaker selective pressure acting on Chs in species that attract pollinators or the stronger selective pressure on F3h in plant species where the gene expression was not associated with pigmentation. The observations suggest that additional factors could affect the evolution of these genes. One such factor could be an effect of gene duplication with further division of functions among gene copies and relaxed selective pressure acting on them. Additional tests with an appropriate dataset combining data on duplicated gene sequences and their functions in the flavonoid biosynthesis pathway are required to test this hypothesis.

Syntopic frogs reveal different patterns of interaction with the landscape: A comparative landscape genetic study of Pelophylax nigromaculatus and Fejervarya limnocharis from central China

Amphibians are often considered excellent environmental indicator species. Natural and man‐made landscape features are known to form effective genetic barriers to amphibian populations; however, amphibians with different characteristics may have different species–landscape interaction patterns. We conducted a comparative landscape genetic analysis of two closely related syntopic frog species from central China, Pelophylax nigromaculatus (PN) and Fejervarya limnocharis (FL). These two species differ in several key life history traits; PN has a larger body size and larger clutch size, and reaches sexual maturity later than FL. Microsatellite DNA data were collected and analyzed using conventional (F ST, isolation by distance (IBD), AMOVA) and recently developed (Bayesian assignment test, isolation by resistance) landscape genetic methods. As predicted, a higher level of population structure in FL (F ST′ = 0.401) than in PN (F ST′ = 0.354) was detected, in addition to FL displaying strong IBD patterns (r = .861) unlike PN (r = .073). A general north–south break in FL populations was detected, consistent with the IBD pattern, while PN exhibited clustering of northern‐ and southern‐most populations, suggestive of altered dispersal patterns. Species‐specific resistant landscape features were also identified, with roads and land cover the main cause of resistance to FL, and elevation the main influence on PN. These different species–landscape interactions can be explained mostly by their life history traits, revealing that closely related and ecologically similar species have different responses to the same landscape features. Comparative landscape genetic studies are important in detecting such differences and refining generalizations about amphibians in monitoring environmental changes.

P.4.c.001 - Common neurotransmission recruited in (R,S)-ketamine and (2R,6R)-hydroxynorketamine-induced sustained antidepressant-like effects

Several Polygonatum species are important medicinal materials as tonic to cure disorders in China. Because of their different medical effects, it is desired to distinguish them at species level. In addition, to ensure and control their medical quality, it is also important to monitor their chemical changes associated with traditional process. Taking the advantages of Fourier transform infrared spectroscopy (FT-IR) and multivariate analysis, we developed a convenient, fast and reliable approach to discriminate and quality control these materials. Despite similar absorption patterns, each species also presented spectral differences, especially on the FT-IR fingerprint range of 1800-600 cm−1. Second derivative method obviously enlarged those differences and then showed more species-specific features. These spectral differences could be used as powerful discriminating points to distinguish them. PCA results showed that each species separated clearly with their biological replicates grouped together, which indicated that the variance between species is greater than within species, therefore, these species could be distinguishable. Using this approach, the five herbal materials were discriminated successfully in their raw, processed and ethanol extracted formats. On the other hand, visual inspecting infrared spectra of samples from 1 to 9 process steps, absorbance near 1737, 1259, 817 and 780 cm-1 increased gradually but decreased gradually at 927 cm−1. Besides, spectral contour near 1050 cm−1 changed sharply with process treatment. These spectral changes indicated that hydrolyzing polysaccharides into oligo- and mono-saccharides, especially glucose and fructose, are the main chemical changes associated with traditional process. This is consistent with the traditional experience that the processed materials are dark as night and sweet as malt sugar. Meanwhile, our results also indicated that their chemical constituents changed profoundly after process, which might be the chemical basis for raw and processed materials have different medical effects. Based on absorbance at 817 and 780 cm−1 and the color, taste, smell of processed materials followed by energy efficacy, raw materials had to be processed more than 21 h to ensure their quality. This research shows the potential of FT-IR spectroscopy coupled with multivariate analysis to discriminate different herbs and to monitor chemical changes with process and then control their quality. This could be very helpful to ensure the quality, safety, and efficacy of herbs on clinical practices.