Data from: Immunomics of the koala (Phascolarctos cinereus )

The study of the koala transcriptome has the potential to advance our
understanding of its immunome—immunological reaction of a given host to
foreign antigens—and to help combat infectious diseases (e.g.,
chlamydiosis) that impede ongoing conservation efforts. We used Illumina
sequencing of cDNA to characterize genes expressed in two different koala
tissues of immunological importance, blood and spleen. We generated nearly
600 million raw sequence reads, and about 285 million of these were
subsequently assembled and condensed into ~70,000 subcomponents that
represent putative transcripts. We annotated ~16 % of these subcomponents
and identified those related to infection and the immune response,
including Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), major
histocompatibility complex (MHC) genes, and koala retrovirus (KoRV). Using
phylogenetic analyses, we identified 29 koala genes in these target
categories and report their concordance with currently accepted gene
groups. By mapping multiple sequencing reads to transcripts, we identified
56 putative SNPs in genes of interest. The distribution of these SNPs
indicates that MHC genes (34 SNPs) are more diverse than KoRV (12 SNPs),
TLRs (8 SNPs), or RLRs (2 SNPs). Our sequence data also indicate that KoRV
sequences are highly expressed in the transcriptome. Our efforts have
produced full-length sequences for potentially important immune genes in
koala, which should serve as targets for future investigations that aim to
conserve koala populations.