P{hsneo} insertion at position +10 relative to the transcription start site, within the minimal sequences necessary to direct E74A transcription.
Mutants show defects in destruction of the larval salivary glands, having persistant larval salivary glands at the pupal stage.
At the onset of pupation, as staged by head eversion, Eip74EFneo24/Df(3L)81k19 mutant animals exhibit the following phenotypes: 1. Mutant larval midguts are extremely condensed and the adult and larval epithelia have separated such that a defined adult lumen exists. These mutants also form an adult midgut epithelium, and the larval proventriculus and gastric caeca are destroyed. Thus, Eip74EFneo24/Df(3L)81k19 larval midguts appear to be arrested at a stage of destruction that is similar to the midgut of wild-type animals 6-12 h following puparium formation. 2. DNA fragmentation is detected in all larval midgut cells of mutant animals 3. Mutant larval midgut cells appear to die normally and have numerous autophagic structures, including mitochondria in vacuoles, crystalline inclusions, and myelin-like membrane swirls. Between the white prepua stage and head eversion, Eip74EFneo24/Df(3L)81k19 mutant midguts decrease in length by an average of 81% in length compared to 85% in the wild-type.
Eip74EFneo24 mutant pupae exhibit DNA fragmentation in the salivary gland as normal.
Mutant salivary gland cells lack large eosin positive vacuoles and plasma membranes and show variable chromosome banding - phenotypes associated with autophagy initiating in salivary gland cells but not progressing. Salivary gland cells contain nascent autophagic vacuoles composed of rough endoplasmic reticulum enclosing cytoplasmic components including mitochondria and smaller vacuoles.
Approximately 20% of Eip74EFneo24/Df(3L)81k19 animals have salivary glands at 24 hours after puparium formation, in contrast to wild-type pupae where they are completely destroyed by 16 hours after puparium formation.
Homozygous mutant γ neurons (generated in the brain as somatic clones) exhibit no detectable abnormalities in larval or adult stages.
Head eversion is not affected in mutants.
Development of hemizygous pupae progresses normally but tanning is delayed by several hours. Some fail to form a gas bubble or undergo pupation. Homozygous and hemizygous pharate adults dissected from the pupal case display leg twitches and abdominal contractions and are inviable.
Eip74EFneo24, br2Bc-2 has lethal | recessive | prepupal stage phenotype
Eip74EFneo24 is a non-enhancer of phenotype of zipEbr
Eip74EFneo24, br2Bc-2 has imaginal disc phenotype
Eip74EFneo24, br2Bc-2 has puparium cuticle phenotype
Eip74EFneo24, br5 has wing phenotype
Eip74EFneo24, br5 has adult head phenotype
Eip74EFneo24, br5 has leg phenotype
Eip74EFneo24, brrbp-5 has head phenotype
Double heterozygotes with brrbp-5, br5 or br2Bc-2 show no effect on development. Heterozygous brrbp-5 females and mutant brrbp-5 males homozygous for Eip74EFneo24 pupariate normally. Half of each group die during prepupal development, resembling severe phenotype Eip74EFneo24 mutants. 8% display novel phenotypes. Head eversion fails and rudimentary appendages/cryptocephalic head structures develop. 58% of Eip74EFneo24 mutants carrying a single effective dose of br+ arrest during the prepupal period. 20% of these prepupae show a misshapen puparium. A novel microcephalic phenotype results from partial head eversion, though eyes do develop. Leg and wing structures are absent. Lethal phenotype is more severe than either Eip74EFneo24 or br5 alone. More than 25% of Eip74EFneo24 carrying a single effective dose of br+ formed a misshapen puparium. This phenotype is 100% penetrant in a br2Bc-2 mutant background. Most double mutants die during the prepupal stage, earlier than either br2Bc-2 or Eip74EFneo24 mutants alone. In 16% of double mutants eye development proceeds to the point where pigment can be observed, but other discs do not undergo morphogenesis.
A. Spradling.
Cooley et al.
Complements: frc00073. Complements: frc02619. Complements: l(3)0263402634. Complements: l(3)j11B2j11B2.
Late puffs normally active at puparium formation are significantly reduced in size in hemizygous white prepupae, early late and early puffs are relatively unaffected.
Amorphic for the E74A transcription unit.