title: Gene cloning, characterization and expression and enzymatic activities related to trehalose metabolism during diapause of the onion maggot Delia antiqua (Diptera: Anthomyiidae).
abstract: Trehalose represents the main hemolymph sugar in many insects, and it functions in energy metabolism and protection in extreme environmental conditions. To gain an insight into trehalose functions in Delia antiqua diapausing pupae, genes encoding trehalose-6-phosphate synthase (TPS), trehalose-6-phosphatase (TPP) and trehalase (TRE) were identified and characterized. Analysis of the deduced amino acid sequences indicated that these genes were highly similar to each homolog from Diptera insects. Gene expressions and their enzyme activities were also investigated. The differential expressions of TPS and TPP shared very similar trends for summer and winter diapausing pupae. Their enzyme activities were consistent with the gene expressions. Trehalose concentrations in summer- and winter-diapausing pupae were lower at the initial phase (4.37-5.09μg/mg) but increased gradually and peaked in the maintenance phase (10.59-14.36μg/mg); the concentrations then declined in the quiescence phase. We speculated that a higher trehalose content during the maintenance stage may contribute to protein and/or biological membrane stabilization in winter or to desiccation resistance in the summertime. Diapause termination requires a decrease in the trehalose concentration to promote pupal-adult development. The glucose content also varied during the diapausing processes. Our results provide an overview of the differential expression levels of trehalose metabolic enzymes, confirming the important roles of trehalose in diapausing pupae of the onion maggot. Further work remains to explore its actual functions.
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: You-Jin
authors.initials: YJ
authors.lastname: Hao
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: Yu-Juan
authors.initials: YJ
authors.lastname: Zhang
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Ren
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China.
authors.forename: Feng-Ling
authors.initials: FL
authors.lastname: Si
authors.affiliation: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing 401331, China. Electronic address: bin.chen@cqnu.edu.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D064666:Diapause, Insect; D004175:Diptera / Q000737:chemistry / Q000201:enzymology / Q000254:growth & development*; D018507:Gene Expression Regulation, Developmental; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008958:Models, Molecular; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D016415:Sequence Alignment; D014198:Trehalase / Q000235:genetics / Q000378:metabolism; D014199:Trehalose / Q000378:metabolism*
chemical_list: D019476:Insect Proteins; D014199:Trehalose; D005964:Glucosyltransferases; C023180:trehalose-6-phosphate synthase; C023178:trehalose-phosphatase; D010744:Phosphoric Monoester Hydrolases; D014198:Trehalase
keywords: Delia antiqua; Diapause; Trehalase; Trehalose; Trehalose-6-phosphate phosphatase; Trehalose-6-phosphate synthase