<p>U ovom radu sagledan je molekularni diverzitet, filogeografska struktura,<br />prostorna distribucija molekularnog diverziteta, kao i prisustvo selekcionih<br />signala i genetičkih signala lokalnih adaptacija kod 251 jedinke vrste Lepus<br />europaeus (Pallas, 1778) sa teritorije Evrope i Bliskog Istoka, a na osnovu<br />analize varijabilnosti sekvenci D petlje mtDNK, MT-ND2, MT-ND6, MHCDQA, MHC-DQB i TLR2 gena. Uočen je visok nivo parametara molekularnog<br />diverziteta za sve ispitivane molekularne markere. Utvrđeno je postojanje<br />filogeografske strukturiranosti vrste na osnovu mtDNK, kao i asimetričan<br />protok gena jedinki sa teritorije Anadolije na teritoriju Balkana na osnovu D<br />petlje mtDNK, MT-ND2 i MT-ND6 gena, dok je na osnovu sekvenci D petlje<br />mtDNK uočena gotovo tri puta veća stopa protoka gena sa Balkana u centralnu<br />i zapadnu Evropu. Utvrđeno je prisustvo signala poizivne selekcije u okviru<br />MT-ND6 gena, kao i efekat klimatskih parametara (precipitacije) na<br />distribuciju proteinskih varijanti ND6C i ND6F, kao moguća posledica<br />regionalnih adaptacija na razlike u sredinskim uslovima. Pokazano je odsustvo<br />signala filogeografske strukturiranosti na osnovu MHC-DQA, MHC-DQB i<br />TLR2 gena. Uočeno je postojanje prostorne strukturiranosti na osnovu gena<br />imunskog sistema, i definisane su dve prostorne grupe, jedna koja je<br />obuhvatala jedinke sa teritorije Bliskog Istoka, i druga koja je obuhvatala<br />jedinke sa teritorije Evropi. Više vrednosti parametara molekularnog<br />diverziteta uočene su u anadolijskoj grupi, u poređenju sa evropskom grupom.<br />Uočen je signal delovanja pozitivne i negativne selekcije u MHC-DQA i MHCDQB genima, kao i signal negativne selekcije u TLR2 genu. Pokazan je efekat<br />klimatskih parametara na distribuciju najzastupljenijih proteinskih varijanti<br />MHC-DQA i MHC-DQB gena kao indirektni pokazatelj imunogenetičkih<br />adaptacija na sredinski uslovljene pretpostavljene razlike u distribuciji<br />patogena. Mehanizam oblikovanja varijabilnosti MHC gena rezultat je<br />uzajamnog delovanja mutacija, rekombinacija i selekcije.</p> / <p>In this doctoral dissertation, molecular diversity, phylogeographic structure,<br />spatial distribution of molecular diversity, detection of possible selection<br />signals shaping the evolution of these genes, as well as the presence of<br />local/regional adaptations in correlation was examined in 251 brown hares<br />from Europe and the Middle East based on the analyses of mitochondrial D<br />loop, mitochondrially Encoded NADH Dehydrogenase 2 (MT-ND2),<br />mitochondrially Encoded NADH Dehydrogenase 6 (MT-ND6), exon 2 of<br />MHC Class II genes MHC-DQA,MHC-DQB and Toll Like Receptor 2 (TLR2)<br />gene sequences. A high level of molecular diversity was found based on the all<br />applied markers. Strong signal of phylogeographical and spatial structuring<br />was observed for mtDNA, most likely as a consequence of climatic<br />perturbations during the Pleistocene. The evolutionary development of hares<br />from Anatolia/Israel to the Balkans, and furthermore to central and western<br />Europe was suggested by several lines of evidences, which include dating the<br />population demography based on D-loop sequences, the observed migration<br />patterns, results of demographic tests, and apparent reduction in molecular<br />diversity indices along this trajectory. Positive selection acting on MT-ND6<br />gene was detected, together with significant climatic effect shaping the<br />distribution of the most prevalent protein variants found in this gene,<br />supposedly as a consequence to local/regional adaptations due to the<br />environmentally induced different energetic requirements and optimization of<br />OXPHOS genes. On the other side, less evident phylogeographic signal and<br />absence of strong structuring was revealed in MHC genes. High diversity at<br />MHC genes seems to be shaped by the interplay of recombination, selection<br />mechanisms and adaptations. Balancing selection seems to maintain a high<br />molecular diversity within these genes, while directional selection promotes<br />local/regional adaptations to pathogenic landscapes, as indirectly suggested by<br />a significant effect of climatic parameters on the distribution of protein<br />variants in both examined MHC genes.</p>
Identifer | oai:union.ndltd.org:uns.ac.rs/oai:CRISUNS:(BISIS)114414 |
Date | 23 July 2020 |
Creators | Stefanović Milomir |
Contributors | Djan Mihajla, Suchentrunk Franz, Beuković Dejan, Jelić Mihailo |
Publisher | Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, University of Novi Sad, Faculty of Sciences at Novi Sad |
Source Sets | University of Novi Sad |
Language | Serbian |
Detected Language | English |
Type | PhD thesis |
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