Correction: Abcg2a is the functional homolog of human ABCG2 expressed at the zebrafish blood–brain barrier - Joanna R. Thomas; William J. E. Frye; Robert W. Robey; Andrew C. Warner; Donna Butcher; Jennifer L. Matta; Tamara C. Morgan; Elijah F. Edmondson; Paula B. Salazar; Suresh V. Ambudkar; Michael M. Gottesman (Fluids and Barriers of the CNS)