Nucleotide substitution: T?A.
Amino acid replacement: L6term.
T11153658A
L7term | rtv-PA; L7term | rtv-PB; L7term | rtv-PD
L6term
Reported as a mutation from TTA (Leu) to TAA (stop).
At stage 16, the dorsal trunk of the tracheal system is enlarged in the mutant embryos compared to wild type and has a convoluted shape. The luminal chitin cable is disorganised in the trachea of mutant embryos.
At stage 15, the dorsal trunk lumen in rtv11 mutants remains constricted at branch fusions and the tube between fusion junctions becomes excessively overgrown compared to wild-type, exhibiting a cystic-like appearance. Stage 16 rtv11 mutant embryos display irregular tracheal tube shapes, but do not exhibit defects in branch patterning, compared with wild-type embryos. During stage 16, the rtv11 mutant dorsal tube becomes extensively elongated compared with the wild-type trunk. The lumen of the narrower multicellular ganglionic branches is discontinuous in rtv11 mutants at the border of the ventral nerve cord. Lumen expansion from stage 14 to 15 does not involve cell division and relies on coordinated growth of the apical cell surfaces.
Mutant larvae cannot hatch and they die. They are hyperactive and occasionally turn around in the egg case. Mutant larvae appear bloated compared to wild-type larvae in cuticle preparations as the cuticle detaches from the epidermis. The three layers of the larval cuticle are present ultrastructurally, but the epicuticle is discontinuous and frayed and the procuticle is devoid of laminae. The envelope appears unaffected.
The head skeleton of mutant larvae is strongly sclerotized and its characteristic fibrous structure is missing.
The tracheae are undulated in mutant stage 17 embryos compared to wild type and fail to form air-filled tubes.
Homozygous embryos often reverse themselves within the eggshell (8.9% of embryos show this "retroactive" phenotype). When the embryos are mechanically devitellinised the resulting cuticle preparations stretch to a greater extent than wild-type cuticles, resulting in inflated cuticles ("blimp" phenotype). The embryos have defects in the head skeleton and denticle belts.
rtv11 embryos have darkly sclerotinised mouthparts, and are sometimes inverted in the egg case.