Molecular and functional analysis of scalloped recessive lethal alleles in Drosophila melanogaster

The Drosophila melanogaster scalloped (sd) gene is a homolog of the human TEF-1 gene and is a member of the TEA/ATTS domain-containing family of transcript,ion factors. In Drosophila, sd is involved in wing development as well as neural development. Herein, data are presented from a molecular analysis of five recessive lethal sd alleles. Only one of these alleles complements a viable allele associated with an sd mutant wing phenotype, suggesting that functions important for wing development are compromised by the noncomplementing alleles. Two of the wing noncomplementing alleles have mutations that, help to define a VG-binding domain for the SD protein in vivo, and another non-complementing allele has a lesion within the TEA DNA-binding domain. The VC-binding domain overlaps with a domain important for viability of the fly, since two of the sd lethal lesions are located there. The fifth lethal affects a vet undefined Motif lying just outside the VC-binding domain in the C-terminal direction that affects both wing phenotype and viability. This is the first. example linking mutations affecting specific amino acids in the SD protein with phenotypic consequences for the organism.