Characterization and Analysis of Whole Transcriptome of Giant Panda Spleens: Implying Critical Roles of Long Non-Coding RNAs in Immunity

Abstract

Background/Aims: Giant pandas, an endangered species, are a powerful symbol of species conservation. Giant pandas may suffer from a variety of diseases. Owing to their highly specialized diet of bamboo, giant pandas are thought to have a relatively weak ability to resist diseases. The spleen is the largest organ in the lymphatic system. However, there is little known about giant panda spleen at a molecular level. Thus, clarifying the regulatory mechanisms of spleen could help us further understand the immune system of the giant panda as well as its conservation. Methods: The two giant panda spleens were from two male individuals, one newborn and one an adult, in a non-pathological condition. The whole transcriptomes of mRNA, lncRNA, miRNA, and circRNA in the two spleens were sequenced using the Illumina HiSeq platform. EBseq and IDEG6 were used to observe the differentially expressed genes (DEGs) between these two spleens. Gene Ontology and KEGG analyses were used to annotate the function of DEGs. Furthermore, networks between non-coding RNAs and protein-coding genes were constructed to investigate the relationship between non-coding RNAs and immune-associated genes. Results: By comparative analysis of the whole transcriptomes of these two spleens, we found that one of the major roles of lncRNAs could be involved in the regulation of immune responses of giant panda spleens. In addition, our results also revealed that microRNAs and circRNAs may have evolved to regulate a large set of biological processes of giant panda spleens, and circRNAs may function as miRNA sponges. Conclusion: To our knowledge, this is the first report of lncRNAs and circRNAs in giant panda, which could be a useful resource for further giant panda research. Our study reveals the potential functional roles of miRNAs, lncRNAs, and circRNAs in giant panda spleen.