Fig. 2

T Cell Development Is Impaired in irf4a-Deficient Embryos

(A) Location and sequence of the TALEN target site for the irf4a gene.

(B) Sequence flanking the TALEN target site in F2 embryos. The deletion of seven nucleotides is shown in the black box.

(C) Expression of rag1, lck, and tcra in the thymus (red arrow) of the siblings and irf4a mutants at 4 or 5 dpf. The embryos for WISH were obtained from an incross of genotyped heterozygous irf4a mutants.

(D) Cellular structure of the thymus in the control and irf4a morphants at 4 dpf. The transverse sections were observed with TEM. L, lymphocyte; E, thymic epithelial cells. Scale bar, 2 µm.

(E) Confocal images of cmyb:EGFP cells in the thymus of the control or irf4a morphants at 4 dpf. The white circle indicates the thymus region below the otic vesicle (OV), denoted with the white dashed line. Scale bar, 20 µm.

(F) Enumeration of cmyb:EGFP cells in the thymus of the control and irf4a morphants at 4 dpf. p < 0.001.

(G) Expression of cmyb, ikaros, and coro1a in the thymus (red arrow) of the control and irf4a morphants at 3 dpf.

(H) TUNEL assay of the control and irf4a morphants at 3 dpf. The irf4a MOatg was injected into coro1a:EGFP transgenic embryos. The white circle indicates the thymus region behind the eye (E), denoted with the white dashed line. White arrows denote apoptotic cells. Scale bar, 40 µm. All data are mean ± SD.

See also Figure S2.