Sox2-mediated conversion of NG2 glia into induced neurons in the injured adult cerebral cortex.
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ABSTRACT:
SUBMITTER: Heinrich C
PROVIDER: S-EPMC4264057 | biostudies-literature | 2014 Dec
REPOSITORIES: biostudies-literature
Publications
Sox2-mediated conversion of NG2 glia into induced neurons in the injured adult cerebral cortex.
Heinrich Christophe C Bergami Matteo M Gascón Sergio S Lepier Alexandra A Viganò Francesca F Dimou Leda L Sutor Bernd B Berninger Benedikt B Götz Magdalena M
Stem cell reports 20141120 6
The adult cerebral cortex lacks the capacity to replace degenerated neurons following traumatic injury. Conversion of nonneuronal cells into induced neurons has been proposed as an innovative strategy toward brain repair. Here, we show that retrovirus-mediated expression of the transcription factors Sox2 and Ascl1, but strikingly also Sox2 alone, can induce the conversion of genetically fate-mapped NG2 glia into induced doublecortin (DCX)(+) neurons in the adult mouse cerebral cortex following s ...[more]
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Following papain treatment, the tissue was washed three times with 4.5ml of inhibitor buffer containing BSA (1.0mg/ml, Sigma, St. Louis, MO, A-8806), and ovomucoid (also known as trypsin inhibitor, 1.0 mg/ml, Roche Diagnostics Corporation, Indianapolis, IN 109878) and then mechanically dissociated by gentle sequential trituration using a 5ml pipette. Dissociated cells were layered on top of 10ml of high concentration inhibitor solution with 5mg/ml BSA and 5mg/ml ovomucoid and centrifuged at 130g for 5 minutes. The cell pellet was then resuspended in 12 ml Dulbecco’s phosphate-buffered saline (DPBS, Invitrogen, Carlsbad, CA 14287) containing 0.02% BSA and 12.5U/ml DNase and filtered through a 20um Nitex mesh (Sefar America Inc., Depew NY, Lab Pak 03-20/14) to remove undissociated cell clumps. This yields a single cell suspension. Cell health is assessed by trypan blue exclusion. 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Finally, the cell suspension was incubated on an anti-GalC hybridoma coated plate for 30 minutes to harvest newly formed oligodendrocytes. For purification of RNA, the cells were lysed while still attached to the panning plate with Qiazol reagent (Qiagen 217004), and total RNA was purified as described below. Mehtod Part4:To purify endothelial cells, we took advantage of Tie2-EGFP transgenic mice available from Jackson labs. These mice express EGFP under the pan-endothelial Tie2 promotor (Daneman et al., 2010; Motoike et al., 2000). Single cell suspension was prepared and FACS was performed as described above. Method Part5: RNA-Seq was performed on the polyadenylated fraction of RNA isolated from purified cell samples.Two biological replicates were used for each phase.100 ng total RNAs were used for each sequencing library. 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