Molecular analysis of cis-regulatory sequences at the alpha-amylase locus in Drosophila melanogaster.
The Amylase locus in Drosophila melanogaster contains duplicate, divergently transcribed structural genes for alpha-amylase, AmyA and AmyB. A sensitive and reliable transient expression assay was developed for testing amylase activities produced by exogenous Amy genes in somatically transformed larvae of an amylase-null strain of flies. Alleles tested, AmyA and AmyB, came from recombinant clone lambda Dm65, which contains genomic DNA from a Canton-S strain. The transient assay was used in a deletion analysis aimed at locating cis-regulatory sequences within the 5' region of AmyB. Results suggest that upstream regulatory sequences for correct spatial expression of AmyA and AmyB in third-instar larvae are located within 446 and 430 bp of their respective starts for transcription. A sequence required for high levels of AmyB expression was located within its 5' upstream region between the base pairs at -332 and -219. AmyA does not appear to have a comparable regulatory element in its 5'-flanking sequence. Barely detectable expression of AmyB was observed when it was flanked by only 92 bp of upstream sequence. A model is proposed for incomplete coordinate control of the duplicate Amy genes.
Hawley
S A
SA
Department of Zoology, Arizona State University, Tempe 85287-1501.
Doane
W W
WW
Norman
R A
RA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002872:Chromosome Deletion; D004331:Drosophila melanogaster / Q000201:enzymology* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D005796:Genes; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D013379:Substrate Specificity; D000516:alpha-Amylases / Q000235:genetics* / Q000378:metabolism
D000516:alpha-Amylases