Sequence And Organization Of The Complete Mitochondrial Genome Of Hipposideros Armiger,Rhinolophus Luctus, And Petaurista Alborufus

Mitochondrion which possesses its own genome is a fundamental and important organelle that exists in eucaryotic organism. Mitochondrion also participates in a lot of metabolic process which relates with apoptosis, disease and senility. It is also the place of oxidative phosphorylation (OXPHOS) and major place of formation of ATP. Moreover, the mitochondrion possess many biological characteristics such as maternal inheritance, small size, constant gene content, a relatively high mutation rate,very low recombination rate and Simple construction. All those advantages make mitochondrial sequence to be a very useful tool in studies of phylogenetic reconstruction, population genetics, phylogeography and the investigation of population structures at various taxonomic levels.The complete mitochondrial genomes not only privide more information than individual genes, but also provide sets of genome level characteristics which are useful for modeling evolution and phylogenetic reconstruction.These characteristics include gene content and gene arrangment, base composition, models of replication and transcription, secondary structures of tRNA and rRNA genes, and genetic codon varation. With the development of technology, determination of the genome sequence of mitochondrial genome has become more easily. It is become popular that make use of the mitochondrial genome sequence research the evolution of species relationship. Pseudogenes are DNA sequences which share sequence identity with its mitochondrial homologue in nuclear genome. However they are containing important defects which make them unable to produce functional proteins. The pesudogenes were widely found in prokaryotes, including fungi, plants, and metazoan. The existence of pesudogenes will make a lot of interference to the studies which involve in mitochondrial sequence. Nonetheless, they are useful in studies of heredity and evolution. The complete mitochondrial genome of Hipposideros armiger, Rhinolophus luctus, and Petaurista alborufus and a NUMT of Petaurista alborufus were gained to their conservation genetics and subsequent studies. The main research results are as follows:1The complete mitochondrial genomes of Hipposideros armiger and Rhinolophus luctus were amplified with the specific primers which based on available Chiroptera mitochondrial genome sequence, by using the the long and accurate polymerase chain reaction (LA-PCR) and primer walking sequencing methods. The size of Hipposideros armiger and Rhinolophus luctus was16784bp and16775bp respectively. The two new mitochondrial genomes contain two ribosomal RNA genes13protein-coding genes,22transfer RNA genes, and one control region, with an identical order to that of most other vertebrates. We also found that the origin of L-strand replication of Hipposideros armiger and Rhinolophus luctus mitochondrial genome was located in a cluster of five tRNA genes (WANCY) with33bp in size. We determined the control region of Hipposideros armiger and Rhinolophus luctus mitochondrial genome, and identified conserved sequence blocks (CSB) and two extended termination associated sequence (ETAS) within this region, respectively. And we found two tandem repeat sequence in Hipposideros armiger control region, and26bp and6bp in length respectively. However we only identified one11bp long tandem repeat sequence in Rhinolophus luctus control region. Molecular phylogenetic analysis of12available Chiroptera species mitochondrial genome sequences was performed with Bayesian and Maximum parsimony (MP) methods based on sequences from12concatenated heavy-strand encoded protein coding genes. We obtained the similar phylogenetic tree by the two methods. We suggested that the Chiroptera can be divided into two suborders:Yinpterochiroptera and Yangochiroptera.2We designed specific primers which based on the available Rodentia mitochondrial genome sequence to amplify the complete mitochondrial genome of Petaurista alborufus by using the the long and accurate polymerase chain reaction (LA-PCR) and primer walking sequencing methods. And it is16507bp long and contains two ribosomal RNA genes13protein-coding genes,22transfer RNA genes, and one control region, with an identical order to that of most other vertebrates. The origin of L-strand replication of Petaurista alborufus mitochondrial genome is located in a cluster of five tRNA genes (WANCY) with33bp in size. We determined the control region of Petaurista alborufus mitochondrial genome, and identified conserved sequence blocks (CSB) and two extended termination associated sequence (ETAS) within this region. Molecular phylogenetic analysis of33available Rodentia species mitochondrial genome sequences was performed with Bayesian and Maximum parsimony (MP) methods based on sequences from12concatenated heavy-strand encoded protein coding genes.The results provided more evidence to support the previous studies on Rodentia.One pseudogene which is880bp was amplified by the primer pair FS-PS. And it matches with the cytb gene of Petaurista alborufus mitochondrial genome. It covers5.33%of the complete mitochondrial genome of Petaurista alborufus and shared89%sequence identify with its miochondrial counterpart. BLAST search suggested that this pseudogene shares89%to92%nucleotide sequence identity with the mitochondrial cytb gene of the Sciuridae species and92%to95%amino acid sequence identity with the mitochondrial cytb gene of the Sciuridae species. Sequence divergence between the nuclear pseudogene and the mitochondrial homologue analysis suggested that the translocation of this mtDNA fragment into the nuclear genome occurred in6.97-7.67million years ago (MYA).