Email address details are represented as the mean with the SD
Email address details are represented as the mean with the SD. trimethylation of residues K9 and K27. These data suggest that the epigenetic modulation of oligodendrocyte identity is highly conserved across species. 0.05; **** 0.0001). Others and we have previously shown that this acetylation state of lysine residues on histone H3 is usually high in proliferating oligodendrocyte progenitor cells and is catalyzed by histone acetyltransferases (HATs, which place the acetyl group on lysines), while the early stages of differentiation are characterized by the removal of these activating marks catalyzed by histone deacetylases (HDACs) [20,21]. Lineage progression is further characterized by repressive histone methylation of lysine residues K9 and K27, which is usually catalyzed by specific histone methyltransferases for K9 (e.g., EHMT2) [22] and K27 (e.g., EZH2) [23]. As a first step towards characterization of epigenetic changes during oligodendrocyte differentiation of human stem cells, we assessed the transcript levels of histone acetyltransferases, histone deacetylases and histone methyltransferases in the sequential stages described above (Physique 1C). Consistent with the previous report of increased acetylation at myelin gene promoters and enhancers during differentiation [24], expression of the acetyltransferase genes and MYST family showed an increase at the final Im. OL stage of differentiation. On the other hand, the specific activity of class I HDACs (HDAC-1, -2, -3, -8) has been implicated in the development of myelinating oligodendrocytes to initiate chromatin compaction [15]. Transcript levels of and progressively increased from NSCs to Im. OL, while and expression remain comparable at the various Rabbit Polyclonal to GPR113 stages of the differentiation. Next, we examined the expression levels of the major enzymes responsible for the methylation of H3K9 and H3K27. Our results were consistent with previous reports [19] on increased levels of the H3K27-specific methyltransferase during the transition from the NSC stage to the OLIG2 early progenitors stage. In addition, we identified a marked increase of the H3K9-specific methyltransferase (also known as and was upregulated as early as the NSC stage, while and did not display significant patterns of expression across the lineage. In agreement with published evidence on the crucial importance of HDAC11 activity for oligodendrocyte development in rats [26], we detected increased levels of only PROTAC ER Degrader-3 in MBP+ mature oligodendrocytes. The levels of the EED and EZH2, subunits of the enzymatic complex responsible for H3K27 methylation, peaked at the NSC stage and slowly tapered off as OPC differentiated. Surprisingly, EZH1 expression was increased in both ESC-derived Im. OL and iPSC-derived OL (Physique 1C and Physique 2C). Among the enzymes responsible for the di- and tri-methylation of H3K9, EHMT2 expression increased at the OPC and mature oligodendrocyte stages; SUV39H1 expression remained constant over time; and SUV39H2 expression slightly increased from the NSC stage (Physique 2C). To validate the functional significance of PROTAC ER Degrader-3 the transcriptional data on histone modifiers, we asked whether the histone marks in differentiated iPSCs would be consistent with the predicted changes of enzymatic activities. For this reason, we performed double immunofluorescence using antibodies specific for each stage-appropriate oligodendrocyte marker and for the post-translational modifications of lysine residues on histone H3 (Physique 3, Physique 4, Physique 5 and Physique 6). Open in a separate window Physique 3 Immunofluorescence analysis of histone H3 pan-acetylation in iPSC-derived oligodendrocyte lineage cells. (A) Representative images of Day 8 of the oligodendrocyte differentiation protocol co-stained for NSC markers SOX1, NESTIN and the pan-acetylated histone 3 antibody; (B) Images from Day 68 of differentiation co-stained for oligodendrocyte markers OLIG2, SOX10, O4, MBP and H3ac antibody. Scale bar = 25 m. The magnified view of the broken line box area appears as the inset with the individual channels and the merged image. Scale bar = 10 m; (C) Quantitation of the immunofluorescence signal as the mean gray value in PROTAC ER Degrader-3 cells expressing.