title: The period gene: high conservation of the region coding for Thr-Gly dipeptides in the Drosophila nasuta species subgroup.
abstract: In this study, the region corresponding to the Thr-Gly region of the period (per) gene in the Drosophila nasuta subgroup of species was sequenced. The results showed that this region was highly conserved in the D. nasuta subgroup. There were only nine variable sites found in this 300-bp-long region, all located in two small regions highly variable among Drosophila species. No length variation was observed either within this subgroup or in the Yunnan (YN) population of D. albomicans. The deduced amino acid sequences were identical for all 14 taxa in the D. nasuta subgroup, and a stretch of alternating Thr-Gly pairs was not observed in this subgroup. A phylogenetic tree was constructed. The clustering of some species was in general agreement with previous works, but it also raised some question on the phylogenetic relationship between the nasuta species. The data did not implicate the Thr-Gly region playing a role in behavioral isolation in this subgroup of Drosophila.
authors.forename: X Z
authors.initials: XZ
authors.lastname: Zheng
authors.forename: Y P
authors.initials: YP
authors.lastname: Zhang
authors.forename: D L
authors.initials: DL
authors.lastname: Zhu
authors.forename: Z C
authors.initials: ZC
authors.lastname: Geng
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002940:Circadian Rhythm; D017124:Conserved Sequence; D004151:Dipeptides / Q000235:genetics*; D004330:Drosophila / Q000145:classification / Q000235:genetics*; D029721:Drosophila Proteins; D019143:Evolution, Molecular; D017344:Genes, Insect; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics*; D056950:Period Circadian Proteins; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D004151:Dipeptides; D029721:Drosophila Proteins; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; C400974:threonyl-glycine