1. Laboratory of Stem Cell Biology and Developmental Genetics, The Francis Crick Institute, London NW1 1AT, UK.
2. Bioinformatics core, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
3. RNA Networks Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
4. Genetic Modification Service, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.