Polytene chromosomes normal.
Point mutation.
Nondefective in gonad assembly.
Weak ventralised phenotype. No amnioserosa and defects at the anterior segments.
Embryos are ventralised.
No salivary gland defects.
Does not interact with RpII140wimp maternal effect.
Ventralized embryos: rings or patches of ventral denticles along dorsoventral axis. Disruption of germ band extension that leads to the invagination of posterior segments into the interior of the embryo.
Transformation in the cell fate of the dorsal most ectoderm toward a more ventral pathway of development during gastrulation. There is the correct number of body segments and the cuticular pattern elements associated with each element appear to be normal.
Embryos are dorsal defective.
zen7/Df(3R)Scr embryos appear normal up to gastrulation. The germ band does not elongate, and one or two deep clefts appear between the cephalic furrow and posterior midgut rudiment. The embryo may appear twisted about the antero-posterior axis. Segmentation proceeds despite the distortion and the correct number of segments is formed. The head remains external and the CNS is disrupted. Normally non-adjacent segments are joined by stretches of cuticle in the late embryo, and there are disruptions in the larval setal belts. The optic lobe is absent.
Hemizygous mutant phenotype can be rescued by P element mediated transformation of a wild type zen gene. Homozygotes could not be rescued suggesting there may be an additional lethal mutation on the chromosome.
Wakimoto.