Editorial: Functions of Non-Coding RNA in Innate Immunity

Our understanding of the functions that non-coding RNAs play in shaping the immune response is still in its infancy. The breakthroughs in deep sequencing technology have provided us with an unprecedented view of the human genome. The deeper we sequence the more non-coding genes we identify, while the number of protein coding genes remains constant. GENCODE represents the gene set of the ENCODE project and there are currently 15,931 long non-coding RNA (lncRNA) genes, 9,882 small non-coding RNAgenes, and 14,477 Pseudogenes cataloged inGENCODEversion 231. The contribution of each of these genes to biological processes still remains to be determined. In this research topic, we explore recent data surrounding the functions for microRNA (miRNA) as well as lncRNA within Innate Immunity. Innate immune responses to infection involve the production of pro-inflammatory cytokines such as IL-6 and TNFα in addition to the Type I Interferons (IFNs) that play critical roles in anti-viral immunity. In recent years, there have been huge strides made in understanding the contributions of small RNAs such as miRNA to the Innate Immune processes. More recently, our attention has also been drawn to the growing catalog of lncRNAs. miRNAs are ~22 nt in length are function through post-transcriptional regulation of protein coding genes through regulating translation and RNA stability. LncRNA are transcripts greater than 200 nt in length that do not encode for protein. Both miRNAs and lncRNAs are RNA pol II transcripts, that are capped and many are polyadenylated; however, there is also evidence that both lncRNA and miRNA can be transcribed by RNA polymerase III (1, 2). The vast functions for miRNA and lncRNA within the innate immune responses are thoroughly reviewed in this research topic by Foster et al., Stachurska et al., and Imamura and Akimitsu (3–5).