Fig. 2

A. Semiquantitative RT-PCR analysis of lin-28a, lin-28b and lin-41 gene mRNA expression. Total RNA was isolated from wild-type embryos at the indicated developmental stages and analyzed by using specific primers for lin-28a, lin-28b and lin-41. gapdh was used as a control. B. Real-time PCR analysis of let-7a, let-7b and lin-4/miR-125b miRNA expression. Total RNA was isolated from wild-type embryos at the indicated developmental stages. Expression levels of let-7a, let-7b and lin-4/miR-125b was analyzed using TaqMan miRNA assay. C. Developmental expression analysis of zebrafish lin-28a and lin-28b mRNAs by whole mount in situ hybridization. Zebrafish embryos at various stages were hybridized with antisense probes. D, E. Developmental expression analysis of zebrafish lin-41 mRNAs by whole mount in situ hybridization. sox2 and otx2 probes were used as a CNS maker. Arrowhead indicated expression in the CNS.