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Öğe The aquatic diversity of ostracoda, phytoplankton and zooplankton from freshwater cave habitats in Turkey(British Cave Research Association, 2014) Külköylüoğlu, Okan; Yavuzatmaca, Mehmet; Karacaoğlu, Didem; Telli, MuratDuring this study, a total of 13 ostracod, 2 zooplankton and 43 phytoplankton taxa were recorded from 22 aqueous caves visited between 2010 and 2013 in Turkey. Whereas three ostracods (Candona cf. Candida, Eucypris sp., Potamocvpris sp.) were new records for caves in Turkey, two others (Ilyocypris cf. gibba and Pseudocandona eremita) were reported for the second time from Turkey. With the inclusion of these taxa, the number of freshwater ostracods reported from caves globally has increased to 68 taxa, although this is probably an underestimate of the total diversity. The records of two zooplankton species (Diacyclops bisetosus, Tropocyclops prasimts) found in Cumayani Cave (Zonguldak) is not surprising because of their cosmopolitan distribution and habitat preference characteristics. Among the phytoplankton, Bacillariophyta had the highest richness with 22 taxa followed by Cyanobacteria, Chlorophyta and Euglenophyta with 13, 6 and 2 taxa respectively. The results suggest that each cave has its own unigue biological diversity and species richness that should be recognized and studied in detail.Öğe Besin çeşitliliğinin zooplanktonların büyümelerine ve besin tuzları döngüsüne etkileri üzerine laboratuvar çalışması(2002) Beşiktepe, Şengül; Tuğrul, Süleyman; Telli, MuratMayıs 2001 ve Ocak 2002 tarihlerinde kuzeydoğu Akdeniz'de (ODTÜ, DBE Erdemli açıkları) Acartia clausi'nin yumurta ve fekal pelet üretim oranları saptandı. Deneyler üç farklı partükül büyüklüğü içeren (<18, <56 ve <200$\\mu$m) deniz suyunda yapılmıştır. Yumurta ve fekal pelet üretimi her iki örnekleme döneminde yaklaşık 1 yumurta $dişi^{-1}$ $gün^{-1}$ ve 1.5 fekal pelet $^{-1}$ $gün^{-1}$' dür. Üretilen yumurta ve fekal peletler daha çok <18$\\mu$m partikül konsantrayonu ile ilişkilidir.Öğe Comparative de novo transcriptome analysis and random UV mutagenesis: Application in high biomass and astaxanthin production enhancement for Haematococcus pluvialis(Springer, 2023) Telli, Murat; Ünlü, Ercan SelçukBackgroundAstaxanthin is a natural carotenoid with strong antioxidant capacity. The high demand on astaxanthin by cosmetic, food, pharmaceutical and aquaculture industries promote its value in the biotechnological research. Haematococcus pluvialis Flotow 1844 has been characterized as one of the most promising species for natural astaxanthin biosynthesis. Even though H. pluvialis as an advantage in producing astaxanthin, its slow grow-yield limits usage of the species for large-scale production.Methods and ResultsIn this study we generated mutated H. pluvialis strain by using one-step random UV mutagenesis approach for higher biomass production in the green flagellated period and in turn higher astaxanthin accumulation in red stage per unit algae harvest. Isolated mutant strains were tested for the astaxanthin accumulation and yield of biomass. Among tested strains only mutant strain designated as only MT-3-7-2 showed a consistent and higher growth pattern, the rest had shown a fluctuated and then decreased growth rate than wild type. To demonstrate the phenotypical changes in MT-3-7-2 is associated with transcriptome, we carried out comparative analysis of transcriptome profiles between MT-3-7-2 and the wild type strains. De novo assembly was carried out to obtain the transcripts. Differential expression levels for the transcripts were evaluated by functional annotation analysis.ConclusionsData showed that increased biomass for the MT-3-7-2 strain was different from wild type with expression of transcripts upregulated in carbohydrate metabolism and downregulated in lipid metabolisms. Our data suggests a switching mechanism is enrolled between carbohydrate and lipid metabolism to regulate cell proliferation and stress responses.Öğe Comparative phylogenic analyses of cave-And surface-water Ostracoda from northwest Anatolia based on mitochondrial CO-I(British Cave Research Association, 2016) Telli, Murat; Külköylüoğlu, Okan; Bozdağ, Ozan Gönensin; Yavuzatmaca, MehmetThe class Ostracoda comprises one of the most diverse taxonomic groups within the subphylum Crustacea. Because of their unique community structure, species diversity and richness, ostracods can be used as indicator species of changes in aquatic conditions. In this study the phylogenetic relationships of 16 individual ostracods were investigated. Mitochondrial CO-I genes of eight species, belonging to six genera, collected from surface and cave environments were analyzed. Phylogenetic relationships were calculated using Bayesian, Maximum Likelihood (ML), and Neighbour Joining (NJ) methods, and the topology of all calculations were consistent with each other in that they showed a close phylogenetic relationship and monophyletic clustering within and between most individual genera of Heterocypris, Candona, Psychrodromus. Cave samples did not show clear separation from surface samples. Cave and surface species of the genus Candona are placed as sister groups in Bayesian and NJ trees, but are paraphyletic in ML. Cave and surface samples of Ilyocypris bradyi are sister groups in NJ but paraphyletic in ML and Bayesian analyses. © British Cave Research Association 2016.Öğe Effects of gradual and sudden changes of salinity and light supply for astaxanthin production in Haematococcus pluvialis (Chlorophyceae)(E Schweizerbartsche Verlagsbuchhandlung, 2020) Telli, Murat; Şahin, GünceAstaxanthin, a carotenoid naturally synthesized by Haematococcus pluvialis, is economically important for the nutraceutical, pharmaceutical and food industries due to its high antioxidant and anti-inflammatory properties. We investigated astaxanthin accumulation in H. pluvialis after stepwise versus suddenly increased light supply and salt (NaCl) concentrations. Light was increased from 75 to 150, and then to the final intensity of 350 mu mol photons m(-2) s(-1) in three-day intervals. The effect of gradually increased salt concentration was examined with two steps from 0.2 to the final concentration of 0.8 % (w/v) in three-day intervals. The overall induction period for astaxanthin accumulation was 13 days. Out of all treatments, stepwise increased light supply resulted in highest cell viability and highest astaxanthin accumulation with 15.76 +/- 0.88 mg g(-1) dry mass. It is an energy-saving, appropriate strategy to achieve optimal astaxanthin accumulation. It moreover resulted in the least biomass loss, which is caused by the provided stress conditions.Öğe Effects of Green Light Supplementation with Red and Blue Combinations of LED Light Spectrums On The Growth of Chlamydomonas Reinhardtii (Chlorophyta)(2022) Telli, Murat; Aljamili, Dina Nabil MohammadLight management strategy regarding optimum spectral composition is a critical factor in microalgae cultivation to improve biomass and biosynthesis of valuable bioactive compounds. Recent advance in LED light technology provides unparallel opportunity to test effects of specific wavelength on physiological response of algae. In this study, we investigated effects of white, monochromatic and combination of red (628 nm) and blue (462 nm) light in the ratio of 1: 1; 2: 1 and 1: 2 at the total light intensity of 40 ?mol photons m-2 s-1 on the growth of Chlamydomonas reinhardtii. Moreover, effects of green light (518 nm) supplementation on growth of algae, green light (518 nm) was added gradually into the combination of red:blue (1:2) at the light intensity of 3, 6, 9, 12 and 15 ?mol photons m-2 s-1 as an expense of red and blue light intensity at the ratio of 1:2. Results reveal that growth rate of C. reinhadhtii was found in the order of red:blue (1: 2) > red:blue (2: 1) > red:blue (1: 1) > red > white> blue. Green light supplementation applied as 3 ?mol photons m-2 s-1 resulted in statistically significant higher optical density and dry weight than R:B (1: 2) used as control group in the experiment. Chlorophyll-a concentrations were found significantly higher in all green light supplementation than control group. Seems that 3 ?mol photons m-2 s-1 supplementation of green light together with red:blue combination results in a significant promotion on growth rate, chlorophyll-a and dry weight of C. reinhardtii.Öğe Effects of moderate high temperature and UV-B on accumulation of withanolides and relative expression of the squalene synthase gene in Physalis peruviana(Tubitak Scientific & Technical Research Council Turkey, 2020) Şahin, Günce; Telli, Murat; Ünlü, Ercan Selçuk; Pehlivan Karakaş, FatmaPhysalis peruviana L. (Cape gooseberry) is a source for a variety of phytocompounds such as withanolides, withanone, withaferin A, and withanolide A. These withanolides are high-value drug candidates due to their various pharmacological properties. To meet the increasing demands for these compounds, plant cell technology offers a reliable alternative. Exogenous addition of elicitors is considered the most effective strategy for enhanced production of secondary metabolites. In this study, we investigated changes in withanolide accumulation and characterized the gene expression level changes of squalene synthase enzyme in P. peruviana shoot cultures exposed to mild nonlethal heat stress (45 degrees C for 2 and 5 h) and UV-B radiation (313 nm for 15 min and 3 h). We demonstrated significant changes in withanolide content with 7.86- and 12.5-fold increases for 2- and 5-hmild high-temperature exposure times, respectively. Exposure to UV-B also changed the withanolide content by 7.22- and 7-fold increases for 15 min and 3 h exposure times, respectively. The relative expression level of squalene synthase gene showed consistent results with1.80- and 10.13-fold increases in withanolide for 2- and 5-h mild high-temperature exposure times, and 1.34- and 2.01-fold increases with 15 min and 3 h UV-B exposure times, respectively.Öğe Genetic and morphologic diversity of Pseudophoxinus (Cyprinidae): implication for conservation in Anatolia(Springer, 2015) Telli, Murat; Kence, AykutPseudophoxinus a freshwater fish genus shows remarkable diversification with high number of endemic species in Anatolia. Most of the species of the genus are categorized as endangered for conservation in IUCN Red List due to water abstraction and habitat destruction. The aim of the study is to investigate genetic and morphological structure of Pseudophoxinus populations using allozyme, microsatellite markers and geometric morphometrics (eight landmarks). Sample collection was performed from eight localities for four different Pseudophoxinus species (P. Crassus, P. battalgili, P. egridiri, P. sp) in Anatolia in 2006. Genetic variation was assessed by using six microsatellite and ten allozyme loci. In total, 39 alleles for allozymes and 103 alleles for microsatellites were encountered in all populations. Mean observed heterozygosity was found in the range of 0.0143-0.0875 in allozymes and 0.146 to 0.463 in microsatellites. Significant morphological and genetic differentiation was measured among P. Crassus populations that may indicate to be considered different units in conservation action plans. There was no population differentiation detected by morphological and genetic measurements among P.battalgili populations. Bayesian individual assignment from Structure software revealed that P. battalgili populations are highly mixed in four sampling areas.Öğe Genetic and morphological divergences between wild and captive-bred populations of Salmo trutta abanticus(Wiley, 2017) Telli, Murat; Gürleyen, BüşraSalmo trutta abanticus is a non-anadromous trout species native to Lake Abant and Seven Lakes in Turkey. A restocking programme by captive breeding was initiated in 1999 to support S. trutta abanticus population. Reared 2-year-old juveniles from randomly caught wild parental individuals in Macka breeding farm were introduced into Lake Abant. We aimed to compare genetic and morphological divergences between wild-and captive-bred populations using seven microsatellite loci and geometric morphometric measurements. A significant genetic and morphological divergences were detected between all population in F-st and canonical variate analysis based on geometric morphometric with 10 homolog landmark. Eighty-six microsatellites alleles were recorded across loci. Number of private alleles, observed alleles and observed heterozygosity are statistically significant higher in Macka captive-bred population than Lake Abant and Seven Lakes populations. Of 42 tests, three departures from Hardy-Weinberg equilibrium were detected in all populations after Bonferroni correction. Two pairs of loci (Ssa85 - Str73 and Str73-Str543) in Macka, one pairs of loci (Ssa85-Str73) in Abant and two pairs of loci (Ssa85-Str60 and Str73-Str543) in Seven Lakes populations show linkage disequilibrium. Population structure analysed with Structure software showed three genetic groups (Delta K = 3) in our studied populations. Relatedness estimates show higher mean relatedness values (r = 0.220 +/- 0.230) for Macka captive-breed population than wild populations of Abant Lake and Seven Lakes (r = 0.140 +/- 0.210 and r = 0.170 +/- 0.200 respectively).Öğe Small RNA sequencing based identification of MiRNAs in daphnia magna(Public Library Science, 2015) Ünlü, Ercan Selçuk; Gordon, Donna M.; Telli, MuratSmall RNA molecules are short, non-coding RNAs identified for their crucial role in post-transcriptional regulation. A well-studied example includes miRNAs (microRNAs) which have been identified in several model organisms including the freshwater flea and planktonic crustacean Daphnia. A model for epigenetic-based studies with an available genome database, the identification of miRNAs and their potential role in regulating Daphnia gene expression has only recently garnered interest. Computational-based work using Daphnia pulex, has indicated the existence of 45 miRNAs, 14 of which have been experimentally verified. To extend this study, we took a sequencing approach towards identifying miRNAs present in a small RNA library isolated from Daphnia magna. Using Perl codes designed for comparative genomic analysis, 815,699 reads were obtained from 4 million raw reads and run against a database file of known miRNA sequences. Using this approach, we have identified 205 putative mature miRNA sequences belonging to 188 distinct miRNA families. Data from this study provides critical information necessary to begin an investigation into a role for these transcripts in the epigenetic regulation of Daphnia magna.Öğe Sucul mağara ostrakotlarının (crustacea) ekolojik, morfolojik ve genetik özelliklerinin belirlenmesi(2013) Külköylüoğlii, Okan; Telli, Murat-Öğe Transcriptional response and functional target analyses of miRNA and mRNA to planktivorous fish kairomone exposure in Daphnia magna(E Schweızerbartsche Verlagsbuchhandlung, 2021) Telli, Murat; Gordon, Donna M.; Ünlü, Ercan SelçukThe discovery of regulatory functions for microRNAs (miRNA) and recently described miRNA profiles for Daphnia (Brachiopoda, Cladocera) make it an ideal system to probe for epigenetic regulation of predator avoidance mechanisms in aquatic ecosystems. In this study we report that exposing D. magna to kairomone released by predatory fish from birth to the first reproduction resulted in the differential expression of the four miRNAs tested: miR-7, miR-34, miR-317, and miR-375. Normalized transcript levels for each miRNA were found to vary across the exposure period with no clear conserved pattern of expression despite functional target analyses by Gene Ontology (GO), Clusters of Orthologous Groups of proteins (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicating that predicted miRNA target genes are likely involved in related biological activities. Analysis of mRNA transcripts (Hsp70, Hsp90 (HSP = heat shock protein), actin, AKT-interacting protein (AKT), Glycogen synthase (GYS) and Insulin growth factor receptor (IGFR)) identified in the literature as kairomone-mediated genes, were also carried out. Similar to that obtained for miRNAs, the mRNA relative expression levels showed varying degrees of temporal regulation across the exposure time with the two heat shock transcripts exhibiting elevated levels at early and late time points of exposure while the AKT, GYS, and IGFR transcripts had a general decrease in relative expression during the first 96 hours. Differential mRNA expression data supports the conclusion that kairomone mediated response is regulated by cost of general biological processes and that of survival under long-term kairomone stress. These studies lay the foundation for future work aimed at linking miRNAs and their target transcripts to changes in the signaling events that govern Daphnia response to kairomone specific stress.
