Genetic and molecular studies of apterous: A gene implicated in the juvenile hormone system of Drosophila

Abstract

The apterous (ap) gene in Drosophila melanogaster encodes a homeodomain transcription factor. It is required for the development of the wings and of a subset of embryonic muscles. The gene has been implicated in the juvenile hormone (JH) system because mutations in ap lead to JH deficiency, and are associated with defective histolysis of the larval fat body, arrested vitellogenesis, sterility, and aberrant sexual behavior, all of which are dependent on JH. We describe here the use of hemizygotes and germ-line clones, of X-ray- and hybrid dysgenesis-induced lethal ap alleles to determine the primary role of the gene during development. We find that ap lethality is polyphasic, but occurs primarily at the larval and pupal stages. The lethal phenotype is not associated with any overt morphological abnormality, suggesting that death occurs from a systemic malfunction. Strong interallelic complementation for the wing phenotype was found between some ap mutations induced by X-rays or by hybrid-dysgenesis. By Northern blot analysis, we demonstrate an increase in ap expression in pupae and adults as compared to embryos and larvae, suggesting that it is developmentally regulated. Finally, primer extension is used to determine the transcription start site of the gene.

Transcriptome analysis of reproductive tissue and intrauterine developmental stages of the tsetse fly (Glossina morsitans morsitans)

“…The effects of the knockout of this gene in Drosophila are an absence of wing and haltere development, absence of development of a group of embryonic muscles and juvenile hormone deficiency due to defects in secretory cells in the corpora allata. Indirect effects due to the absence of juvenile hormone include female sterility due to arrest of oogenesis, abnormal larval fat body breakdown, aberrant sexual behavior and premature death in adults [23]. …”

Enhancer Blocking and Transvection at the DrosophilaapterousLocus

“…Transvection at the apterous locus: Here we present evidence for transvection at the Drosophila apterous locus. While interallelic complementation at ap has been previously reported (Shtorch et al 1995), the ap alleles were not molecularly characterized. Consequently, it was not clear whether the complementation between these alleles involved trans-regulatory interactions or occurred at the level of the mutant ap gene products.…”

Juvenile hormone regulation of Drosophila aging

“…A classic genetic approach used the apterous mutant, which regulates development in wing, muscle and axons, and neuroendocrine control of juvenile hormone as well as other neuropeptides [24-28]. More recently, the P{Gal4} insertion ( Aug21 ) was found to be expressed in larval corpora allata [29] and Riddiford et al [30] used Aug21 to drive UAS- grim to induce apoptosis in larval corpora allata (CA).…”