Updated sequence information for this Drosophila species is no longer provided by FlyBase. Gene model annotations for this species are now updated and maintained at NCBI, using the gnomon automated annotation pipeline. See the NCBI page ‘Eukaryotic genomes annotated at NCBI’.
The FlyBase BLAST tool will continue to support queries against the reference genome of this species, but not queries against annotated transcripts or proteins. For the current release, there is no JBrowse or GBrowse view of the gene model annotations for this species.
The FlyBase archived release FB2017_05 includes the last NCBI annotation update for this species that was imported into FlyBase. That sequence data can be accessed from archived gene reports, via the archived GBrowse tool, and via archived bulk-data downloads.
Amy, amy2, Amylase
Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see JBrowse for alignment of the cDNAs and ESTs to the gene model.
For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.
Molecular evolution of the Amy multigenes in Drosophila has been investigated.
Interspecific variation of α-Amylase activities in 18 Drosophila species and the response patterns of enzyme activity to dietary carbohydrates at the larval and adult stages are examined. Glucose repression is conserved among species at both stages while starch induction is mainly observed in larvae. Results may suggest that the regulatory systems responsible both for the response to environment and developmental expression are different among Drosophila species.
Southern blot analysis with a probe containing the D.melanogaster Amy-p gene demonstrated that D.pseudoobscura.pseudoobscura carries three Amy genes. When injected into D.melanogaster Amy- flies Dpse\Amy1 was expressed at high levels, Dpse\Amy2 at very low levels and Dpse\Amy3 was not expressed at all. The amylase region is contained within a series of highly polymorphic inversions. Genomic restriction maps were generated of the Amy region. Polymorphic variants were tested in pairwise combinations and strong linkage disequilibrium was found among the gene arrangements. The inversion polymorphism is estimated to be 2 million years old.
The functional locus is in chromosome X2, at a site homologous to section 73A of its sibling species. A duplicated copy is also present but fails to produce a functional product in transient somatic expression assays. In situ hybridization studies suggest that two other sites in the X2 chromosome might contain inactive sequences belonging to the Amy gene family. The Amylase locus in D.pseudoobscura.pseudoobscura is a multigene family of one, two or three copies on the third chromosome. Three Amylase genes, Dpse\Amy1, Dpse\Amy2 and Dpse\Amy3, differ by 0.5% of their nucleotides, each gene has a putative intron. From sequence data it is possible to infer that Dpse\Amy2 and Dpse\Amy3 are more closely related to each other than either is to Dpse\Amy1. Nucleotide substitution analyses reveal that Dpse\Amy1 has selection against synonymous substitution and Dpse\Amy2 has selection against nonsynonymous substitution, or Dpse\Amy2 has recently undergone a gene conversion with Dpse\Amy1. Dpse\Amy3 is nonfunctional and subject to random genetic drift.
Transient expression assays were used in somatic transformation experiments to functionally test the status of the Amy genes in D.melanogaster embryos.
