AATF/Che-1 localizes to paraspeckles and suppresses R-loops accumulation and interferon activation in Multiple Myeloma

We investigated the interactions of AATF/Che1 with paraspeckles complex in Multiple Myeloma(MM) cells by looking at its relationship with lncRNA NEAT1_1(NEAT1) and the essential paraspeckles proteins. By analyzing ChIP- and ChIRP-sequencing of MM cells, we assessed that the interaction between AATF/Che1 and NEAT1 occurs also onto DNA and detected the sites where they co-localize. To better characterize the interaction, we studied the effects of interfering AATF/Che1 or NEAT1 on co-localizing sites through ChIP-seq with NEAT1 interfered (GapmerNEAT1) and ChIRP-seq with AATF/Che1 interfered (siChe). We found that NEAT1 is essential in maintaining the paraspeckles complex onto those sites. Moreover, by exploring DRIP-seq data with siChe, we also detected that AATF/Che1 and NEAT1 localize on R-loops, RNA:DNA hybrid structure involved in DNA transcription and repair. A depletion of AATF/Che1 causes a further increase of those hybrid structures and the activation of the immune response in MM, in particular the interferon (IFN) activation. To further explore these findings, we performed RNA-seq with siChe and GapmerNEAT1 which confirm that AATF/Che-1 down-regulation induces a strong up-regulation of genes involved in IFN response. Examination of RNA-seq, ChIRP-seq, DRIP-seq and ChIP-seq in KMS27 cell lines before and upon Che1 interference. RNA-seq, ChIP in KM27 cell lines before and upon gapmer NEAT1.