Pear1 expression in the zebrafish. (A) mRNA PEAR1 expression during fish development measured by RT-PCR (dpf, days postfertilization). (B) RT-PCR of Pear1 and CD41 in adult blood in 2 different samples. (C) Whole-mount in situ hybridization (WISH) of Pear1 at 24 hpf with a Pear1 anti-sense probe. (D) Expression in somites. (E) Expression in a putative yolk sac gland. Expression in the nervous system: midbrain-hindbrain boundary (F) and spinal cord neurons (G). (H) Control WISH of Pear1 at 24 hpf with a Pear1 sense probe. Faint Pear1 (I) and clear Gata-1 (J) expression in the caudal region.