Ng2 creert2

All animal experiments were approved by the University of Tasmania Animal Ethics (A0013741, A0016151 and A0018606) and Institutional Biosafety Committees and were carried out in accordance with the Australian code of practice for the care and use of animals for scientific purposes. Pdgfrα-H2BGFP (stock # 007669) [Pdgfrα-histGFP^{93 (link),94 (link)}], Sun1-eGFP (stock # 021039)^{95 (link)}, Ng2-CreER^T2 (stock # 008538)^{8 (link)} and PLP1-CreERT (stock # 005975)^{96 (link)} mouse lines were purchased from Jackson Laboratories. Postnatal day (P) 0-2 Pdgfrα-histGFP neonates were genotyped using a BlueStar flashlight (Nightsea, Lexington USA) to detect GFP expression in the brain, paws and ears. Mice expressing Cre-recombinase or eGFP were genotyped by PCR^{97 (link)} using the following primer sequences: Cre 5′ CAGGT CTCAG GAGCT ATGTC CAATT TACTG ACCGTA and Cre 3′ GGTGT TATAAG CAATCC CCAGAA; GFP 5′ CCCTG AAGTTC ATCTG CACCAC and GFP 3′ TTCTC GTTGG GGTCT TTGCTC. Mice were maintained on a C57BL/6 background and inter-crossed to generate male and female offspring for experimental use. Mice were weaned >P30 to ensure appropriate myelin development, were group housed with same-sex littermates in Optimice micro-isolator cages (Animal Care Systems, Colorado, USA), and were maintained on a 12 h light/dark cycle at 20 °C with uninhibited access to food and water.

All experiments were performed in compliance with protocols approved by the Institutional Animal Care and Use Committee at Cold Spring Harbor Laboratory according to protocol 20-3. The following mouse lines were obtained from the Jackson Laboratory: C57Bl/6J (JAX, 000664), NG2-CreER^T2 (B6.Cg-Tg(Cspg4-Cre/Esr1*)BAkik/J; JAX, 008538) and Rosa26-CAG-LsL-tdTomato (B6.Cg-Gt(ROSA)26Sor^{tm14(CAG-tdTomato)Hze}/J (Ai14); JAX, 007914). NG2-CreER^T2 mice were bred with Ai14 mice inhouse to yield NG2-CreER^T2tdTomato mice in which OPCs are labeled with tdTomato on tamoxifen (TAM) administration. Except when noted, animals were housed in normal 12-h light:12-h dark cycles at average temperatures of 68–70 °F and 54–58% humidity. Analyses were performed on equal numbers of male and female mice at postnatal days (P)10, P20, P27 and P90. Live imaging was performed on animals between 2 and 6 months of age. No sex differences were observed in this study.