Amylase gene expression in intraspecific and interspecific somatic transformants of Drosophila.
The Amylase locus in Drosophila melanogaster normally contains two copies of the structural gene for alpha-amylase, a centromere-proximal copy, Amy-p, and a distal copy, Amy-d. Products of the two genes may display discrete electrophoretic mobilities, but many strains known to carry the Amy duplication are characterized by a single amylase electromorph, e.g., Oregon-R, which produces the mobility variant AMY-1. A transient expression assay was used in somatic transformation experiments to test the functional status of the Amy genes from an Oregon-R strain. Plasmid constructs containing either the proximal or distal copy were tested in amylase-null hosts. Both genes produced a functional AMY-1 isozyme. Constructs were tested against an AMY-3 reference activity produced by a coinjected plasmid that contains the Amy-d3 allele from a Canton-S strain. With reference to the internal control, the Amy-p and Amy-d genes from Oregon-R expressed different relative activity levels for AMY-1 in transient assays. The transient expression assay was successfully used to test the functional status of Amy-homologous sequences from strains of other species of Drosophila characterized by a single amylase elctromorph, namely, Drosophila pseudoobscura ST and Drosophila miranda S 204. The amylase-null strain of D. melanogaster provided the hosts for these interspecific somatic transformation experiments.
Hawley
S A
SA
Department of Zoology, Arizona State University, Tempe 85287-1501.
Norman
R A
RA
Brown
C J
CJ
Doane
W W
WW
Anderson
W W
WW
Hickey
D A
DA
D000681:Amylases / Q000096:biosynthesis / Q000235:genetics*; D000818:Animals; D003001:Cloning, Molecular; D004330:Drosophila / Q000235:genetics*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D007527:Isoenzymes / Q000235:genetics*; D010957:Plasmids; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014170:Transformation, Genetic
D007527:Isoenzymes; D000681:Amylases