The sequence and de novo assembly of hog deer genome.

Hog deer (Axis porcinus) is a small deer species in family Cervidae and has been undergoing a serious and global decline during the past decades. Chengdu Zoo currently holds a captive population of hog deer with sufficient genetic diversity in China. We sequenced and de novo assembled its genome sequence in the present study. A total of six different insert-size libraries were sequenced and generated 395 Gb of clean data in total. With aid of the linked reads of 10X Genomics, genome sequence was assembled to 2.72 Gb in length (contig N50, 66.04 Kb; scaffold N50, 20.55 Mb), in which 94.5% of expected genes were detected. We comprehensively annotated 22,473 protein-coding genes, 37,019 tRNAs, and 1,058 Mb repeated sequences. The newly generated reference genome is expected to significantly contribute to comparative analysis of genome biology and evolution within family Cervidae.

Complete mitochondrial genome sequence of the Asian golden cat, Catopuma temminckii.

In this study, the mitochondrial genome of Asian golden cat (Catopuma temminckii) is sequenced. The mitochondrial genome was 16,985 bp long, including 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, 1 control region and 1 origin of light-strand replication. The overall base composition of the mitochondrial genome was 32.76% A, 27.49 % T, 25.75 % C, and 13.99 % G. The complete mitochondrial genome of Catopuma temminckii could contribute to understanding taxonomic status and phylogenetic relationship of genus Catopuma.

Giant panda BAC library construction and assembly of a 650-kb contig spanning major histocompatibility complex class II region.

BACKGROUND: Giant panda is rare and endangered species endemic to China. The low rates of reproductive success and infectious disease resistance have severely hampered the development of captive and wild populations of the giant panda. The major histocompatibility complex (MHC) plays important roles in immune response and reproductive system such as mate choice and mother-fetus bio-compatibility. It is thus essential to understand genetic details of the giant panda MHC. Construction of a bacterial artificial chromosome (BAC) library will provide a new tool for panda genome physical mapping and thus facilitate understanding of panda MHC genes. RESULTS: A giant panda BAC library consisting of 205,800 clones has been constructed. The average insert size was calculated to be 97 kb based on the examination of 174 randomly selected clones, indicating that the giant panda library contained 6.8-fold genome equivalents. Screening of the library with 16 giant panda PCR primer pairs revealed 6.4 positive clones per locus, in good agreement with an expected 6.8-fold genomic coverage of the library. Based on this BAC library, we constructed a contig map of the giant panda MHC class II region from BTNL2 to DAXX spanning about 650 kb by a three-step method: (1) PCR-based screening of the BAC library with primers from homologous MHC class II gene loci, end sequences and BAC clone shotgun sequences, (2) DNA sequencing validation of positive clones, and (3) restriction digest fingerprinting verification of inter-clone overlapping. CONCLUSION: The identifications of genes and genomic regions of interest are greatly favored by the availability of this giant panda BAC library. The giant panda BAC library thus provides a useful platform for physical mapping, genome sequencing or complex analysis of targeted genomic regions. The 650 kb sequence-ready BAC contig map of the giant panda MHC class II region from BTNL2 to DAXX, verified by the three-step method, offers a powerful tool for further studies on the giant panda MHC class II genes.