The long non-coding RNA expression profile of Coxsackievirus A16 infected RD cells identified by RNA-seq

Coxsackievirus A16(CVA16) is one of major pathogens of hand, foot and mouth disease(HFMD) in children. Long non-coding RNAs(Inc RNAs) have been implicated in various biological processes,but they have not been associated with CVA16 infection. In this study, we comprehensively characterized the landscape of Inc RNAs of normal and CVA16 infected rhabdomyosarcoma(RD)cells using RNA-Seq to investigate the functional relevance of Inc RNAs. We showed that a total of 760 Inc RNAs were upregulated and 1210 Inc RNAs were downregulated. Out of these dysregulated Inc RNAs, 43.64% were intergenic, 22.31% were sense, 15.89% were intronic, 8.67% were bidirectional, 5.59% were antisense, 3.85% were s RNA host Inc RNAs and 0.05% were enhancer. Six dysregulated Inc RNAs were validated by quantitative PCR assays and the secondary structures of these Inc RNAs were projected. Moreover, we conducted a bioinformatics analysis of an Inc RNAs(ENST00000602478) to elucidate the diversity of modification and functions of Inc RNAs. In summary, the current study compared the dysregulated Inc RNAs profile upon CVA16 challenge and illustrated the intricate relationship between coding and Inc RNAs transcripts. These results may not only provide a complete picture of transcription in CVA16 infected cells but also provide novel molecular targets for treatments of HFMD.

RANKL-responsive epigenetic mechanism reprograms macrophages into bone-resorbing osteoclasts

Monocyte/macrophage lineage cells are highly plastic and can differentiate into various cells under different environmental stimuli. Bone-resorbing osteoclasts are derived from the monocyte/macrophage lineage in response to receptor activator of NF-κB ligand (RANKL). However, the epigenetic signature contributing to the fate commitment of monocyte/macrophage lineage differentiation into human osteoclasts is largely unknown. In this study, we identified RANKL-responsive human osteoclast-specific superenhancers (SEs) and SE-associated enhancer RNAs (SE-eRNAs) by integrating data obtained from ChIP-seq, ATAC-seq, nuclear RNA-seq and PRO-seq analyses. RANKL induced the formation of 200 SEs, which are large clusters of enhancers, while suppressing 148 SEs in macrophages. RANKL-responsive SEs were strongly correlated with genes in the osteoclastogenic program and were selectively increased in human osteoclasts but marginally presented in osteoblasts, CD4+ T cells, and CD34+ cells. In addition to the major transcription factors identified in osteoclasts, we found that BATF binding motifs were highly enriched in RANKL-responsive SEs. The depletion of BATF1/3 inhibited RANKL-induced osteoclast differentiation. Furthermore, we found increased chromatin accessibility in SE regions, where RNA polymerase II was significantly recruited to induce the extragenic transcription of SE-eRNAs, in human osteoclasts. Knocking down SE-eRNAs in the vicinity of the NFATc1 gene diminished the expression of NFATc1, a major regulator of osteoclasts, and osteoclast differentiation. Inhibiting BET proteins suppressed the formation of some RANKL-responsive SEs and NFATc1-associated SEs, and the expression of SE-eRNA:NFATc1. Moreover, SE-eRNA:NFATc1 was highly expressed in the synovial macrophages of rheumatoid arthritis patients exhibiting high-osteoclastogenic potential. Our genome-wide analysis revealed RANKL-inducible SEs and SE-eRNAs as osteoclast-specific signatures, which may contribute to the development of osteoclast-specific therapeutic interventions.