Involvement of long noncoding RNAs in the pathogenesis of autoimmune diseases

Fig. 1. Classification of by their genomic location relative to nearby protein-coding genes. (i) Intergenic lncRNAs: lncRNAs located between protein-coding genes; (ii)Antisense lncRNAs: lncRNAs transcribed in the opposite direction of nearby protein-coding genes, and span over at least one exon; (iii)Intronic lncRNAs: lncRNAs that originate from intronic regions of protein-coding genes; (iv) Bidirectional lncRNAs: lncRNAs that initiate transcription in a divergent fashion from the promoter of nearby protein-coding gene.

Fig. 2. Mechanisms of lncRNA functions. (i) lncRNAs mediate recruitment of chromatin modifying complexes to specific genome loci; (ii) The process of splicing and transcription of lncRNAs regulate nearby protein-coding gene; (iii) Enhancer-like elements existing in lncRNA loci regulate gene expression; (iv) lncRNAs regulate transcription by interaction with transcription factors and transcriptional coactivators; (v) lncRNAs act as ceRNA to modulate expression of genes targeted by microRNAs; (vi) lncRNAs bind to mRNA and alter its stability and translation activity; (vii) lncRNAs regulate posttranslational modification, subcellular localization, activation and degradation of protein by forming lncRNA-protein complexes. Pol II: RNA polymerase-II; RISC complex: RNA-induced silencing complex.

Fig. 3. Important lncRNAs involved in the pathogenesis of RA.