Fig. 2

syntabulin is responsible for the tkk mutant phenotype. (A) Linkage mapping. The zebrafish tkk locus was initially mapped near the SSLP marker z1543. Seven BAC clones were used to construct a physical map. Linkage analysis (numbers indicate recombinants per meiosis), sequence analysis of BAC clones and database searches revealed that there were 12 candidate genes in the chromosomal region. (B) Quantification of syntabulin (gene 6 in A) expression in wild-type and tkk embryos (expression in wild type taken as 100; *, P<0.01; the average ±s.d. is shown). zdhhc3 (zinc-finger, DHHC-type containing 3, gene 3) and e(y)2 (enhancer of yellow gene, gene 8) are located in the same chromosomal region as syntabulin and were used as controls. The expression of other genes in this chromosomal region is shown in Table S1 in the supplementary material. (C-F) Expression and localization of syntabulin RNA in an unfertilized wild-type egg (5 minutes after activation, C), in a 1-cell stage wild-type embryo (20 mpf, D), an 8-cell stage wild-type embryo (E), and in a 1-cell stage tkk embryo (F). Lateral views; A, animal pole; Vg, vegetal pole. (G) Molecular nature of the syntabulin^tkk4 allele. PCR detection of the insertion in wild-type and tkk embryos (n=3 each). Scale bars: 200 μm.