Interallelic complementation at the Drosophila melanogaster gastrulation defective locus defines discrete functional domains of the protein.
Genetics
; 159(2): 635-45, 2001 Oct.
Article
em En
| MEDLINE
| ID: mdl-11606540
ABSTRACT
The gastrulation defective (gd) locus encodes a novel serine protease that is involved in specifying the dorsal-ventral axis during embryonic development. Mutant alleles of gd have been classified into three complementation groups, two of which exhibit strong interallelic (intragenic) complementation. To understand the molecular basis of this interallelic complementation, we examined the complementation behavior of additional mutant alleles and sequenced alleles in all complementation groups. The data suggest that there are two discrete functional domains of Gd. A two-domain model of Gd suggesting that it is structurally similar to mammalian complement factors C2 and B has been previously proposed. To test this model we performed SP6 RNA microinjection to assay for activities associated with various domains of Gd. The microinjection data are consistent with the complement factor C2/B-like model. Site-directed mutagenesis suggests that Gd functions as a serine protease. An allele-specific interaction between an autoactivating form of Snake (Snk) and a gd allele altered in the protease domain suggests that Gd directly activates Snk in a protease activation cascade. We propose a model in which Gd is expressed during late oogenesis and bound within the perivitelline space but only becomes catalytically active during embryogenesis.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Serina Endopeptidases
/
Proteínas de Drosophila
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Drosophila melanogaster
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Alelos
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Teste de Complementação Genética
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Genetics
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Estados Unidos