Drosophila glue gene Sgs-3: sequences required for puffing and transcriptional regulation.
The 68C intermolt puff of Drosophila melanogaster contains a cluster of three glue protein genes, Sgs-3, Sgs-7, and Sgs-8. By analysis of chromosomal rearrangements which break near the glue gene cluster, we have established that a region of no more than 20 kb is required for normal expression of the glue genes and for formation of the 68C puff. Using P element-mediated transformation, we have introduced defined segments of the 68C region into the fly genome and assayed the expression of the Sgs-3 gene. Based on the criteria of correct tissue- and stage-specific expression, transcription of an RNA of appropriate size and abundance, and production of an sgs-3 protein, the correctly regulated expression of the Sgs-3 gene requires less than 3.4 kb of total flanking sequences, approximately 2.3 kb 5' and 1.1 kb 3'. Formation of a new intermolt puff at the site of insertion is not observed for all transformants which produce high levels of Sgs-3 RNA. Only transformants in which the introduced DNA from 68C also contains the Sgs-7 and Sgs-8 genes cause a new intermolt puff at the chromosomal location of the insert.
D000818:Animals; D001483:Base Sequence; D002875:Chromosomes / Q000648:ultrastructure; D004247:DNA / Q000235:genetics; D004274:DNA, Recombinant; D004331:Drosophila melanogaster / Q000235:genetics*; D005786:Gene Expression Regulation; D005967:Glue Proteins, Drosophila; D010957:Plasmids; D012313:RNA / Q000235:genetics; D012469:Salivary Glands / Q000648:ultrastructure; D012471:Salivary Proteins and Peptides / Q000235:genetics*; D014158:Transcription, Genetic; D014170:Transformation, Genetic
D004274:DNA, Recombinant; D005967:Glue Proteins, Drosophila; D012471:Salivary Proteins and Peptides; D012313:RNA; D004247:DNA