線粒體蛋白編碼基因（MPCG）序列被廣泛地用于分析物種的適應(yīng)性進(jìn)化、系統(tǒng)進(jìn)化關(guān)系,也用于物種鑒定,其有效性在很多分類單元中都進(jìn)行了評(píng)估。但是在象科動(dòng)物的系統(tǒng)研究較少,如猛犸象的線粒體基因如何適應(yīng)寒冷、干旱的環(huán)境;細(xì)胞色素b（Cyt-b）和COI基因的種間變異以及在鑒別象科動(dòng)物的有效性;和如何就線粒體基因有效鑒別象科動(dòng)物,同時(shí)還能有效排除其他物種及人源DNA的污染等方面少有報(bào)道。本研究針對(duì)三種現(xiàn)生象（即亞洲象、非洲草原象和非洲森林象）和已滅絕的猛犸象,通過(guò)13個(gè)完整的MPCG序列,檢測(cè)猛犸象對(duì)干旱寒冷環(huán)境適應(yīng)性選擇的證據(jù);對(duì)比評(píng)價(jià)Cyt-b和COI部分短序列區(qū)分4種象科動(dòng)物的有效性;開(kāi)發(fā)一種基于PCR的物種鑒定方法。首先,我們分析了 75頭分布廣泛的長(zhǎng)毛象的13個(gè)線粒體蛋白質(zhì)編碼基因序列,繼進(jìn)行陽(yáng)性選擇的信號(hào)檢測(cè),生化和蛋白質(zhì)結(jié)構(gòu)分析以及生化和同源蛋白分析。結(jié)果顯示:6個(gè)MPCGs基因（ND1、ND4、ND5、ND6、ATP6和Cyt-b）中的11個(gè)氨基酸位點(diǎn)顯示出正向選擇,一些突變能夠影響線粒體復(fù)合體Ⅰ中蛋白-蛋白相互作用和氧化磷酸化過(guò)程,尤其是ATP6和Cyt-b殘基的突變能夠影響代... 

【文章來(lái)源】：東北林業(yè)大學(xué)黑龍江省 211工程院校 教育部直屬院校

【文章頁(yè)數(shù)】：136 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
摘要
Abstract
1 Literature Review:evolutionary analysis and genetic species identification ofelephantids: current knowledge and gaps
    1.1 Introduction to evolution and evolutionary relationship among elephantids
    1.2 Threats and present status of elephants
    1.3 The role of wildlife forensics in curtailing poaching and ivory trade
    1.4 Species concept and principles of species identification
    1.5 Current methods of identifying species
        1.5.1 Morphology
        1.5.2 DNA-based species identification
    1.6 Statistical methods for DNA species identification
        1.6.1 Similarity based method
        1.6.2 Genetic distance strategy
        1.6.3 Tree-based method
        1.6.4 Diagnostic nucleotide method
    1.7 Challenges in DNA based species identification
    1.8 Elephantids identification using Cyt-b and COI genes
    1.9 Intra-and interspecific divergence among elephantids based on mtDNA
    1.10 Purpose and main objectives of research
        1.10.1 Purpose and general objective
        1.10.2 Main objectives of the research
2 Positive selection in the mitochondrial protein-coding genes of woolly mammoths
    2.1 Introduction
    2.2 Methods
        2.2.1 Sequence collection
        2.2.2 Alignment and selection analyses
        2.2.3 Protein modelling and structural analyses
    2.3 Results
        2.3.1 Phylogenetic analyses
        2.3.2 Physicochemical property changes
        2.3.3 Amino acid substitutions in OXPHOS complex 1
        2.3.4 Amino acid substitutions in OXPHOS complexes Ⅲ,Ⅳ and Ⅴ
    2.4 Discussion
3 Assessing the effect of the reduced fragments sizes of cytochrome b and COI geneson species identification of elephantids
    3.1 Introduction
    3.2 Materials and methods
        3.2.1 Extraction, amplification and sequencing of DNA
        3.2.2 Sequence alignment and analyses
        3.2.3 Phylogenetic resolution analysis
        3.2.4 Similarity based species assignment
    3.3 Results
        3.3.1 Sequence conservation and variability
        3.3.2 Intra-and interspecific pairwise distances
        3.3.3 Phylogenetic resolution
        3.3.4 Success rate of similarity based identifications
    3.4 Discussion
4 Species identification of extant and extinct elephantid specimens using a shortfragment of cytochrome b gene
    4.1 Introduction
    4.2 Materials and methods
        4.2.1 Sample collection and DNA isolation
        4.2.2 Designing primers
        4.2.3 Primer Validation
    4.3 Results
        4.3.1 Reproducibility and specificity
        4.3.2 Resolution for species identification
        4.3.3 Sensitivity
    4.4 Discussion
Conclusion
References
Appendix
Academic papers published during the study
Acknowledgements



本文編號(hào)：3072300