Project description:The Chinese giant salamander (Andrias davidianus) is one of the most important ecological breeding species with distinct characteristics and is cultured in many locations throughout China. In the present study, the transcriptome of A. davidianus spleen tissue, that had challenged with Citrobacter freundii, was analyzed using Illumina sequencing technology. The result was compared to a heathy control group. After assembly and annotation, 128,540 transcripts were generated with a median length of 349 bp. Comparative expression analysis indicated 1,995 differentially expressed genes (DEGs), 812 of which were up-regulated and 1,183 were down-regulated. Furthermore, DEGs were classified into three gene ontology categories, 535 of which were annotated to 237 KEGG pathways. Finally, six immune-related DEGs involved in the immune-related pathways were randomly selected for scrutinization. This work provides valuable data for an improved understanding the defense mechanisms of A. davidianus against bacterial pathogens at the transcriptional level.
Project description:Background:Milu, also known as Père David's deer (Elaphurus davidianus), was widely distributed in East Asia but recently experienced a severe bottleneck. Only 18 survived by the end of the 19th century, and the current population of 4500 individuals was propagated from just 11 kept by the 11th British Duke of Bedford. This species is known for its distinguishable appearance, the driving force behind which is still a mystery. To aid efforts to explore these phenomena, we constructed a draft genome of the species. Findings:In total, we generated 321.86 gigabases (Gb) of raw DNA sequence from whole-genome sequencing of a male milu deer using an Illumina HiSeq 2000 platform. Assembly yielded a final genome with a scaffold N50 size of 3.03 megabases (Mb) and a total length of 2.52 Gb. Moreover, we identified 20 125 protein-coding genes and 988.1 Mb of repetitive sequences. In addition, homology-based searches detected 280 rRNA, 1335 miRNA, 1441 snRNA, and 893 tRNA sequences in the milu genome. The divergence time between E. davidianus and Bos taurus was estimated to be about 28.20 million years ago (Mya). We identified 167 species-specific genes and 293 expanded gene families in the milu lineage. Conclusions:We report the first reference genome of milu, which will provide a valuable resource for studying the species' demographic history of severe bottleneck and the genetic mechanism(s) of special phenotypic evolution.
Project description:Eighteen of 43 (41.8%) Père David's deer from Dafeng Elk National Natural Reserve, China, were positive for Anaplasma phagocytophilum based on real-time FRET-PCR and species-specific PCRs targeting the 16S rRNA or msp4. To our knowledge this is the first report of A. phagocytophilum in this endangered animal.
