Fig. 7
HOTAIRM1 interacts with repressive modifiers EZH2, G9a, and Dnmts to sequester them away from the promoter of HOXA1 gene. a RNA-IP analysis of HOTAIRM1 interaction with histone methyltransferases EZH2, G9a and DNA methyltransferases Dnmt3a, Dnmt3b, Dnmt1 in A172 cells. One pair of primer was used to detect HOTAIRM1, the lane being 381 bp which represents the 3′ end of two variants. b A working model showing the possible role of HOTAIRM1 in the HOXA1 gene regulation. In the normal brain, G9a, EZH2, and Dnmts enrichment lead to repressive histone modification H3K9me2, H3K27me3 and DNA methylation of the promoter of HOXA1 gene, resulting in gene expression inhibition. In GBM cells, HOTAIRM1 interacts with G9a, EZH2, and Dnmts to sequester them away from the promoter of HOXA1 gene. Histone H3K9, H3k27, and DNA are demethylated in the HOXA1 promoter, changing the chromatin state into being open and active, and resulting in subsequent transcriptional activation