Reprogramming of Fibroblasts to Oligodendrocyte Progenitor-like Cells Using CRISPR/Cas9-Based Synthetic Transcription Factors

• Published in: Stem cell reports 2019-12, Vol.13 (6), p.1053-1067
• Main Authors: Matjusaitis, Mantas, Wagstaff, Laura J., Martella, Andrea, Baranowski, Bart, Blin, Carla, Gogolok, Sabine, Williams, Anna, Pollard, Steven M.
• Format: Article
• Language: English
• Subjects: Animals; Biomarkers; Cellular Reprogramming - genetics; CRISPR-Cas Systems; CRISPR-Cas9; dCas9; designer transcription factors; Fibroblasts - cytology; Fibroblasts - metabolism; Gene Editing; Gene Expression; lineage conversion; Mice; mouse embryonic fibroblasts; neural stem cells; oligodendrocyte; Oligodendrocyte Precursor Cells - cytology; Oligodendrocyte Precursor Cells - metabolism; Oligodendroglia - cytology; Oligodendroglia - metabolism; RNA, Guide, CRISPR-Cas Systems; Transcription Factors - genetics; Transcription Factors - metabolism; Transcriptional Activation
• ISSN: 2213-6711; 2213-6711
• DOI: 10.1016/j.stemcr.2019.10.010

Cell lineage reprogramming via transgene overexpression of key master regulatory transcription factors has been well documented. However, the poor efficiency and lack of fidelity of this approach is problematic. Synthetic transcription factors (sTFs)—built from the repurposed CRISPR/Cas9 system—can activate endogenous target genes to direct differentiation or trigger lineage reprogramming. Here we explored whether sTFs could be used to steer mouse neural stem cells and mouse embryonic fibroblasts toward the oligodendrocyte lineage. We developed a non-viral modular expression system to enable stable multiplex delivery of pools of sTFs capable of transcriptional activation of three key oligodendrocyte lineage master regulatory genes (Sox10, Olig2, and Nkx6-2). Delivery of these sTFs could enhance neural stem cell differentiation and initiated mouse embryonic fibroblast direct reprograming toward oligodendrocyte progenitor-like cells. Our findings demonstrate the value of sTFs as tools for activating endogenous genes and directing mammalian cell-type identity. [Display omitted] •Eight dCas9VP160 synthetic transcription factors (sTFs) delivered with one plasmid•All-in-one plasmid containing eight sTFs can simultaneously activate three genes•Neural stem cell differentiation to OPC is enhanced by Sox10 activation with sTF•sTFs activating Sox10, Olig2, and Nkx6-2 drive MEF transdifferentiation to OPCs In this article, Pollard and colleagues show that multiple dCas9VP160-based synthetic transcription factors (sTFs) can be delivered into mammalian cells using single all-in-one (Ai1) expression plasmid. When key master regulators—Sox10, Olig2, and Nkx6-2—are targeted by such sTFs, mouse embryonic fibroblasts can be forced to transdifferentiate to oligodendrocyte precursor-like cells.