Blimp-1^KG09531/+ mutants show significantly advanced timing of pupation compared to controls.

Blimp-1^KG09531 homozygous embryos are grossly inflated and have pale ectodermal cuticle with smaller denticle belts compared to controls.

In the tracheal dorsal trunk of stage 16 Blimp-1^KG09531 homozygous embryos, protrusions of the apical plasma membrane are irregular with occasionally extended flat regions and the envelope is discontinuous when compared to controls.

In the tracheal dorsal trunk of stage 17 Blimp-1^KG09531 homozygous embryos, (but not heterozygotes) chitin levels are reduced; tanedial folds run parallel to the tube axis; the breadth of the taenidial folds is highly variable; F-actin bundles fail to form rings in most cases or run parallel to the tube axis; apical plasma membrane of cells (except node cells) lack anteroposterior elongation while distinct apical cell shape of the node cells is not altered when compared to controls.