Identification of proteins and developmental expression of RNAs encoded by the 65A cuticle protein gene cluster in Drosophila melanogaster
Résumé
Proteins of the third instar larval cuticle of Drosophila melanogaster, LCP5-LCP9, were purified and their N-terminal sequences determined. Three of these proteins (LCP5, 6, and 8) were found to be encoded by two multicopy genes previously mapped to the gene cluster at 65A 5-6 on the left arm of the third chromosome. The analysis of the patterns of developmental expression of the 8 distinct genes at this site showed that all but two were expressed during larval life. The patterns fell into three groups: one where expression was all through larval life, one where expression was primarily in the third instar, and one only during the production of the adult cuticle. One duplicated gene was not expressed in the Canton S strain at any time from the embryo to adult ecdysis. These findings indicate that there is not a unique set of cuticle proteins in the third versus the first and second instar larval cuticles and indicates that overlapping gene sets in several different gene clusters encode the proteins of the cuticle of different developmental stages.
Mots clés
Amino Acid Sequence
Animals
Chromosome Mapping
Drosophila melanogaster/*genetics/growth & development
Gene Expression Regulation
Developmental
Genes
Insect
Insect Proteins/*genetics/isolation & purification
Larva/genetics/growth & development
Molecular Sequence Data
Multigene Family
RNA/*genetics
Sequence Homology
Amino Acid