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    Genetic and morphometric comparisons of populations of Lacerta diplochondrodes Wettstein, 1952 (Squamata: Lacertidae) in Turkiye
    (Taylor & Francis Ltd, 2023) Kaya, Nilgün; Özuluğ, Oya; Tosunoğlu, Murat; Eldem, Vahap
    The diverse climate types and geographical structures across Anatolia result in a high level of species diversity. Among these, the lizard species Lacerta diplochondrodes exhibits several distinct populations, with some of them recognized as subspecies. The primary objective of our study was to investigate whether populations from Thrace and the Western Black Sea region of Turkiye differ from other documented populations. For this purpose, we conducted a comprehensive analysis of genetic and morphometric parameters. For the genetic analysis, we utilized the COI and cyt-b gene regions as molecular markers. Principal Component Analysis (PCA) and Canonical Discriminant Analysis (CDA) were used for the morphometric analyses to differentiate populations. Our findings indicate that a population found in the Bolu region in Western Black Sea region of Turkey differs from the other populations both in morphometric and genetic traits. The L. d. diplochondrodes and L. d. cariensis populations represent sister lineages, and they are both genetically and morphologically only weakly differentiated. These two lineages are therefore referred to as L. d. diplochondrodes. Overall, four different lineages can be distinguished in Turkiye, out of which the lineage of the Western Black Sea region (Bolu lineage) is described for the first time.
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    Öğe
    Phenotypic plasticity in Mediterranean gorgonians Eunicella singularis and Paramuricea clavata at high temperature and low pH
    (Elsevier B.V., 2025) Belivermiş, Murat; Kılıç, Önder; Özalp, Hasan Bariş; Demiralp, Selcan; Gezginci-Oktayoglu, Selda; Eldem, Vahap; Şahin, Berna
    The Mediterranean gorgonian octocorals are threatened by acidification, warming and marine heat waves. Phenotypic plasticity is critical for slow-growing gorgonians, as adaptation through natural selection might not be fast enough to cope with rapid environmental changes. DNA methylation (DNAm) is a type of (trans)generational phenotypic plasticity mechanism that may help slow-growing corals better withstand the effects of environmental changes by adjusting gene expression. This study aimed to assess the physiological responses and epigenetic modifications associated with phenotypic plasticity in the Mediterranean gorgonians Eunicella singularis and Paramuricea clavata exposed to warming (+4 °C), acidification (?0.35 pHT units) and their combination over two weeks. In addition, RNA-Seq-based differential gene expression analysis was performed for E. singularis. High temperature, low pH and their combination did not cause tissue death or necrosis in the corals. Polyp activity in E. singularis increased at high temperatures. Warming increased oxygen consumption in both species. Energy reserves (protein, lipid, carbohydrate contents) were not affected by temperature, pH or their interaction in either species. The global DNA methylation (gDNAm) rate was ten times higher in P. clavata than in E. singularis. There was no effect of temperature, pH or their interaction on gDNAm in E. singularis. gDNAm in P. clavata decreased at high temperatures and low pH. Differential gene expression analysis indicated that high temperature induced the most extensive transcriptional changes in E. singularis, while low pH alone had the least impact. The combined stress of high temperature and low pH also led to notable up- and downregulation of gene expression. Heat stress in E. singularis caused widespread downregulation of transcription factors (TFs), particularly those in the zf-C2H2, AP-2, and HMG families. Conversely, the IRF, RFX, P53, and NRF1 families were upregulated, highlighting the complex transcriptional response to thermal stress. Overall, these physiological, transcriptomic and epigenetic alterations have the potential to negatively impact the fitness of these emblematic species and their associated ecosystems. © 2025 Elsevier B.V.