Molecular analysis of a gene in a developmentally regulated puff of Drosophila melanogaster.
AUTOR(ES)
Muskavitch, M A
RESUMO
An increase in the concentration of the steroid hormone ecdysone in late larval life triggers a profound change in the pattern of polytene chromosome puffs in the Drosophila melanogaster salivary gland. One of the preexisting puffs that regress as the ecdysone concentration increases is located at the 3C11-12 bands, the site of the Sgs-4 gene, which codes for the sgs-4 protein, one of the proteins in the salivary glue secretion. We have isolated cloned segments of chromosomal DNA that define a 60-kilobase region containing the 0.9-kilobase Sgs-4 gene, and we have determined its position and orientation within this region. Fine structure restriction endonuclease mapping shows that approximately 45% of this gene consists of tandemly repeated sequences of 21 base pairs that occupy most of its 5' half, indicating that most of the amino-terminal half of the sgs-4 protein consists of tandemly repeated amino acid sequences of seven residues. We also report on the amount of the Sgs-4 mRNA as a function of developmental stage and in nine different strains, four of which produce little or no sgs-4 protein. Three of the null strains produce minute amounts of the mRNA and one yields none, whereas the five sgs-4 producing strains yield abundant amounts. The mRNAs frm these strains exhibit different lengths, which correlate with different gene lengths that appear to result from different numbers of the repeated sequences in their tandem arrays.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=350503Documentos Relacionados
- Molecular analysis of the yellow gene (y) region of Drosophila melanogaster.
- Chromosome puff activity and protein synthesis in larval salivary glands of Drosophila melanogaster.
- Localization of RNA from heat-induced polysomes at puff sites in Drosophila melanogaster.
- Molecular cloning and analysis of small optic lobes, a structural brain gene of Drosophila melanogaster.
- Characterization of a putative transcription factor gene expressed in the 20-OH-ecdysone inducible puff 74EF in Drosophila melanogaster.