Nuclear paraspeckle assembly transcript 1 (NEAT1) is the crucial structural platform of paraspeckles, which is one type of nuclear bodies. As a stress-induced lncRNA, the expression of NEAT1 increases in response to viral infection, but little is known about the role of NEAT1 or paraspeckles in the replication of herpes simplex virus-1 (HSV-1). Here, we demonstrate that HSV-1 infection increases NEAT1 expression and paraspeckle formation in a STAT3-dependent manner. NEAT1 and other paraspeckle protein components, P54nrb and PSPC1, can associate with HSV-1 genomic DNA. By binding with STAT3, PSPC1 is required for the recruitment of STAT3 to paraspeckles and facilitates the interaction between STAT3 and viral gene promoters, finally increasing viral gene expression and viral replication. Furthermore, thermosensitive gel containing NEAT1 siRNA or STAT3 siRNA effectively healed the skin lesions caused by HSV-1 infection in mice. Our results provide insight into the roles of lncRNAs in the epigenetic control of viral genes and into the function of paraspeckles.Electronic supplementary materialThe online version of this article (doi:10.1007/s00018-016-2398-4) contains supplementary material, which is available to authorized users.

The accumulation of intracellular β-amyloid peptide (Aβ) is important pathological characteristic of Alzheimer’s disease (AD). However, the exact underlying molecular mechanism remains to be elucidated. Here, we reported that Nuclear Paraspeckle Assembly Transcript 1 (NEAT1), a long n on-coding RNA, exhibits repressed expression in the early stage of AD and its down-regulation declines neuroglial cell mediating Aβ clearance via inhibiting expression of endocytosis-related genes. We find that NEAT1 is associated with P300/CBP complex and its inhibition affects H3K27 acetylation (H3K27Ac) and H3K27 crotonylation (H3K27Cro) located nearby to the transcription start site of many genes, including endocytosis-related genes. Interestingly, NEAT1 inhibition down-regulates H3K27Ac but up-regulates H3K27Cro through repression of acetyl-CoA generation. NEAT1 also mediates the binding between STAT3 and H3K27Ac but not H3K27Cro. Therefore, the decrease of H3K27Ac and/or the increase of H3K27Cro declines expression of multiple related genes. Collectively, this study first reveals the different roles of H3K27Ac and H3K27Cro in regulation of gene expression and provides the insight of the epigenetic regulatory mechanism of NEAT1 in gene expression and AD pathology. Electronic supplementary material The online version of this article (10.1007/s00018-019-03074-9) contains supplementary material, which is available to authorized users.

No abstract