Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Freshwater systems offer important opportunities to investigate the consequences of intrinsic biological and extrinsic environmental factors on the distribution of genetic variation, and hence population genetic structure. Drainages serve to isolate populations and so preserve historical imprints of population processes. Nevertheless, dispersal between and within drainages is important if the biology of the species confers a good dispersal capability. Knowledge of the population genetic structure or phylogeographic patterns of Australia's freshwater fish fauna is generally depauperate, and the present study aimed to increase this knowledge by investigating patterns of genetic diversity in three Australian species of freshwater fish. I was interested in the relative importance of dispersal capability, the hierarchical nature of stream structure and the consequences of earth history events on patterns of genetic diversity among populations. I examined three species from three families of Australian freshwater fish, Pseudomugil signifer (Pseudomugilidae), Craterocephalus stercusmuscarum (Atherinidae) and Hypseleotris compressa (Gobiidae). These species are abundant, have wide overlapping distributions and qualitatively different dispersal capabilities. I was interested in attempting to unravel how the biological, environmental and historical factors had served to influence the patterns and extent of genetic diversity within each species, thereby inferring some of the important evolutionary processes which have affected Australia's freshwater fauna. I used allozyme and 500-650bp sequences from the ATPase6 mitochondrial DNA (mtDNA) gene to quantify the patterns of genetic variation at several hierarchical levels: within populations, among populations within drainages and among drainages. I collected fish at several spatial scales, from species wide to multiple samples within drainages; samples were collected from the Northern Territory, Queensland and New South Wales. The species with the highest potential for dispersal, H. compressa, exhibited the lowest levels of genetic differentiation as measured at several allozyme loci (H. compressa: FST=0.014; P. signifer FST=0.58; C. stercusmuscarum FST=0.74). Populations of H. compressa also had low levels of mtDNA differentiation, with many recently derived haplotypes which were widespread along the coast of Queensland. This suggested either considerable gene flow occurs or recent demographic change in the populations sampled. As there was no relationship between geographic distance and genetic differentiation, the populations appeared to be out of genetic drift - gene flow equilibrium, assuming the two-dimensional stepping stone model of gene flow. Estimating contemporary gene flow was thus difficult. It was apparent that there has been a recent population expansion and / or contraction of H. compressa populations. It was concluded that there has been considerably more connectivity among populations of H. compressa in the recent past than either of the other study species. Populations of P. signifer showed considerable genetic subdivision at different hierarchical levels throughout the sampled range, indicating gene flow was restricted, especially between separate drainages. Two widely divergent regional groups which had high ATPase6 sequence divergence and approximately concordant patterns at allozyme loci were identified. Interestingly, the groups mirrored previous taxonomic designations. There was also significant subdivision among drainages within regional groups. For example, the adjacent Mulgrave-Russell and Johnstone drainages had individuals with haplotypes that were reciprocally monophyletic and had large allozyme frequency differences. This allowed me to examine the patterns of genetic differentiation among populations within drainages of two essentially independent, but geographically close systems. There was as much allozyme differentiation among populations within subcatchments as there was between subcatchments within drainages, and significant isolation by distance among all populations sampled within a drainage. This suggested that the estuarine confluence between subcatchments was not a barrier to P. signifer, but that distance was an important component in the determination of the distribution of genetic diversity within drainages in P. signifer. There were three main areas of investigation for C. stercusmuscarum: comparing upland and lowland streams of the drainages in north Queensland, investigating the consequences of eustasy on coastal margin populations and examining the intriguing distribution of the two putative sub species, C. s. stercusmuscarum and C. s. fulvus in south east Queensland. First, as populations in upland areas of east coast flowing rivers are above large discontinuities in the river profile, their occurrence is presumably the result of gene flow to and / or from lowland areas, or the result of invasions via the diversion of western flowing rivers. Concordant patterns at both genetic markers revealed that the latter possibility was the most likely, with fixed allozyme differences between upland and lowland populations, and large mtDNA sequence divergence. Indeed, it appeared that there may have been two independent invasions into the upland areas of rivers in North Queensland. Second, lowland east coast populations also had large, although not as pronounced, levels of population subdivision. Lack of isolation by distance, but with a concomitant high level of genetic differentiation among many comparisons, was consistent with a scenario of many small, isolated subpopulations over the range. Interestingly, widespread populations in central Queensland coastal populations (drainages which receive the lowest rainfall) were relatively genetically similar. This was consistent with the widest part of the continental shelf which at periods of lower sea level apparently formed a large interconnected drainage, illustrating the effect of eustatic changes on populations inhabiting a continental margin. Third, putative C. s. fulvus in lowland coastal Queensland drainages were genetically more similar to a population of C. s. fulvus collected from a tributary of the Murray-Darling (western flowing) than they were to adjacent putative C. s. stercusmuscarum. This implied that populations in south east Queensland, north to approximately the Burnett River, appeared to be derived from western flowing streams, and not via dispersal from other lowland east coast populations. Determining the relative importance of intrinsic and extrinsic factors to the development of population genetic structure is a difficult task. The present study demonstrated that the species with the highest dispersal potential had the lowest levels of genetic differentiation, waterfalls can limit gene flow, eustasy acts to join and separate populations leading to complex genetic patterns and that drainage rearrangements are important in determining the distribution of genetic diversity of populations now inhabiting isolated drainages. A difficulty with generalising about population genetic structure in obligate freshwater animals is the unique history of not only each drainage, but also the streams within that drainage and the idiosyncratic biological dynamics of the populations inhabiting those drainages.

Oxidative stress (OS) has been associated with aging and age-related diseases in humans, as well as with the decline in economic trait performance in poultry and other domesticated animals. However, the potential effects of OS on the poultry immune system are not well understood. In addition, the impact of bird genetic variation on redox balance remains to be elucidated. Thus, the central hypothesis of this dissertation is: The bird's adaptive immunocompetence is impacted by their OS level, which is not only influenced by environmental factors, but also related to genetic phenotype of either mitochondrial DNA (mtDNA) or nuclear DNA (nDNA). In the first phase of this study, White Leghorn chickens were provided ethanol at different concentrations in drinking water to induce OS. Biomarkers including malondialdehyde (MDA), glutathione (GSH), and plasma uric acid (PUA) were measured to assess OS before and after ethanol treatment. The adaptive immune response during an OS event was measured by plasma IgG and IgM levels, major lymphoid organ weights, CD4+/CD8+ cell ratio, and histopathological analysis of the immune organs. Results showed that when OS was induced by 10% ethanol, chicken adaptive immune responses decreased; however, when birds were exposed to 2% ethanol, there was an enhancement in antioxidant defense and immune response; These results would suggest a negative correlation between OS level and chicken adaptive immune response. In the second phase of the study, subsets of chickens were selected based on their high (H)- or low (L)-OS to assess for variations in their genetic phenotypes. Using MDA levels, 36 chickens were chosen to scan a 2734-bp region of mtDNA, but no definitive SNP was detected. In another experiment, 40 chickens were conversely selected according to three biomarkers for OS. Although no variation was found at eight SNP loci tested across the mitochondrial genome, mtDNA damage measured by 8-hydroxy-2′-deoxy-guanosine was shown to increase with time, and at higher levels in the high OS birds (p < 0.05). Thses results suggest that long-term high OS levels in chickens may increase the somatic mutation of their mtDNA. In the final phase of this dissertation, the effect of nDNA on OS, measured via a genome-wide association study was performed with 18 H and 18 L chickens using the latest chicken 60k SNP microarray for genotyping. Among 56,483 SNPs successfully genotyped, 13 SNPs across five independent loci were associated with OS at significance level of p ≤ 0.001, and another 144 SNPs were also associated with OS (p ≤ 0.01). These results indicate new loci and related genes for their genetic influence upon redox balance. In general, experiments carried out on White Leghorn chickens here have shown that adaptive immune response is tightly related to changes of OS. Further, genetic variance in nDNA is associated with the risk of high OS or the ability to better resist it. / Ph. D.

Darbo objektas – naujai sukryžminti hibridinės drebulės (Populus tremuloides x Populus tremula) ir karpotojo beržo ( Betula pendula) hibridai. Darbo tikslas – Atlikti tolimąją hibridizaciją ir išauginti augalus-regenerantus nesubrendusių gemalų kultūroje bei įvertinti genetinę įvairovę. Darbo rezultatai. Sukryžminus gauta skirtingi hibridai. Jų įvairovė įvertinta APPD metodu. Išmatavus augimo tempus nustatyta, kad hibridai 16.2 ir 16.4 auga greičiau nei hibridinės drebulės klonai. Ištyrus adaptacijos nesterilioje aplinkoje sąlygas, nustatyta šaknijimosi tempai. Tyrimo metu pastebėta, kad ūgliukų sodinimas į durpių substratą Jiffi tabletėse su šaknimis ir be jų ilgesniam nei 3 mėnesių laikotarpiui, neturi augimo skirtumų. / Aim of the work: new crossbred hybrid aspen (Populus tremuloides x Populus tremula) and birch (Betula pendula) hybrids Objekt of the work: make long hybridization and grow up new regeneration plants in unformed embrio culture and rate genetical variation Results: After crossing get new hybrids. His variation rated by RAPD metod. After measure growing speed, set that hybrids 16.2 and 16.4 growing faster than hybriding aspen clons. In adaptation study set root growing speed. In study notice that plants with root and without in Jiffi tablet peat substratum after 3 month get same height .

Darbo objektas – Populus genties medžiai: Populus alba × Populus tremula (Nr. 20), Populus tremula x Populus alba ( Nr.21), P. tremuloides x P. tremula (Nr.8), P. tremuloides x P. tremula (Nr.3), P. tremuloides x P. tremula (Nr.9), Populus alba (Š16), P. berolinensis. Darbo tikslas – nustatyti tuopų genties medžių hibridų mikrodauginimo in vitro sąlygas, bei augalų- regenerantų išauginimą. Išskirti genominę DNR iš drebulių, naudojant genominės DNR išskyrimo rinkinį NucleoSpin Plant. Darbo metodai - Eksplantų paruošimas sterilinimui ir sterilinimas. Augalų regenerantų kultivavimo sąlygos. Maitinamosios terpės ruošimas, sterilinimas ir sudėtis. Mikroūglių perkėlimas į nesterilias sąlygas. DNR išskyrimas. Darbo rezultatai. Tuopų medžių eksplantų sterilinimui tikslinga naudoti aseptinių tirpalų kombinaciją be „ACE“, kad užtikrinti gyvybingų ir be užkrato eksplantų išlikimą. Grybine infekcija labiausiai užkrėsti berlyninės tuopos eksplantai: užkratas sudarė nuo 72 proc. iki 80 proc. priklausomai nuo eksplantų prigimties. Tuopų genties medžių genotipas turi įtakos morfogenezei audinių kultūroje. Geriausia maitinamoji terpė mikroūglų susidarymui yra Murashige Scoog (MS) su citokininu BA- 0,5 mg/l. Kaliaus susidarymas ir spalva priklauso nuo genotipo. Iš visų tuopų hibridų sparčiausiai augo hibridas Nr. 8 P.( tremuloides x P. tremula). Vidutinis jo augimo greitis- 8,3 mm per 10 dienų. Atlikti DNR tyrimai APPD metodu parodo, kad motinmedžiai ir išauginti augalai in vitro yra... [toliau žr. visą tekstą] / Aim of the work: Genus Populus trees: Populus alba × Populus tremula (Nr. 20), Populus tremula x Populus alba (Nr.21), P. tremuloides x P. tremula (Nr.8), P. tremuloides x P. tremula (Nr.3), P. tremuloides x P. tremula (Nr.9), Populus alba (Š16), P. berolinensis. Object of the work: Investigate poplar genus hybrids in vitro micro reproduction conditions and regenerate plants growth. Investigate poplar genomic DNA using NucleoSpin Plant Kit. Methods: Preparation of explants culture for sterile manner. Plants regenerate rear conditions. Growth media preparation and sterilization. Micro sprout input into unsterile conditions. DNA isolation. Results: For poplar trees explants sterilization is purposeful using aseptic solution combination without “ACE”, to vouch vital and half explants survival. Fungous infection found in berolinensis poplar explants: infections reach from 72 to 80 % depending from explants nature. Poplar genus genotype has impact on morphogenesis in tissue culture. The best growth media is Murashige Scoog (MS) with citotoksine BA- 0,5 mg/l. Callus formation and colaration depends on genotipe. Fastest growth had hybrid No. 8 ( tremuloides x P. tremula) from all poplar hybrids. His mean growth was 8.3 mm per 10 days. RAPD analysis shown that the parent trees and trees race in vitro are the similar (the same).