Figure 1.

TALEN-Induced Deletions Nullify Brachyury Function

(A) TALEN-induced 2- and 7-bp deletions in exon 1 of t (e1.2D) and exon 3 of t2 (e3.7D), and predicted frameshift translations generating truncated proteins of 59 and 170 amino acids (aa). These mutations were selected to generate a double heterozygous X. tropicalis line for the Brachyury paralogs t and t2 (t^e1.2D/+t2^e3.7D/+).

(B) t and t2 transcript levels in hetero- and homozygous embryos as measured by qRT-PCR at early neurula stage (n = 3, mean ± SD). Two-tailed t test: ^∗p ≤ 0.05.

(C) Multi-probe WMISH for various mesoderm cell lineage and derivative markers (actc1; cardiac and skeletal muscle; cav1, notochord; hoxd8, pronephros; myh6, heart; tal1, ventral blood island; tbx6, paraxial mesoderm) in wild-type and Brachyury (t/t2) null (KO) embryos, as well as embryos injected with four MOs targeting t and t2 (t/t2 MO mix) at mid-tailbud stage. Scale bar, 0.5 mm.