... stages subsequent to the blastoderm. We show that the previously described mutation jaws is an amorphic Tc'Kr allele. Pair-rule gene expression in the blastoderm is affected neither in the amorphic mutant nor in Tc'Kr RNAi embryos. Only during subsequent growth of the germ band does pair-rule patterning...

... function. Therefore, the coordinated regulation of several Hox genes by Tc'giant appears to rely on a mechanism involving tight thresholds. Interestingly, the phenotype of jaws ( Sulston and Anderson, 1996 ),a mutant in the Tc'Krüppel gene (A. Cerny, G.B. and M.K.,unpublished) displays a homeotic...