title: Identification of a midgut-specific promoter in the silkworm Bombyx mori.
abstract: The midgut is an important organ for digestion and absorption of nutrients and immune defense in the silkworm Bombyx mori. In an attempt to create a tool for midgut research, we cloned the 1080 bp P2 promoter sequence (P2P) of a highly expressed midgut-specific gene in the silkworm. The transgenic line (P2) was generated via embryo microinjection, in which the expression of EGFP was driven by P2P. There was strong green fluorescence only in the midgut of P2. RT-PCR and Western blot showed that P2P was a midgut-specific promoter with activity throughout the larval stage. A transgenic truncation experiment suggested that regions -305 to -214 and +107 to +181 were very important for P2P activity. The results of this study revealed that we have identified a midgut-specific promoter with a high level of activity in the silkworm that will aid future research and application of silkworm genes.
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Jiang
authors.forename: Tingcai
authors.initials: T
authors.lastname: Cheng
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Dang
authors.forename: Zhengwen
authors.initials: Z
authors.lastname: Peng
authors.forename: Ping
authors.initials: P
authors.lastname: Zhao
authors.forename: Shiping
authors.initials: S
authors.lastname: Liu
authors.forename: Shengkai
authors.initials: S
authors.lastname: Jin
authors.forename: Ping
authors.initials: P
authors.lastname: Lin
authors.forename: Qiang
authors.initials: Q
authors.lastname: Sun
authors.forename: Qingyou
authors.initials: Q
authors.lastname: Xia
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D012831:Bombyx / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D005453:Fluorescence; D041981:Gastrointestinal Tract / Q000166:cytology*; D017344:Genes, Insect; D005818:Genetic Engineering / Q000379:methods; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000235:genetics / Q000378:metabolism; D008845:Microinjections; D008969:Molecular Sequence Data; D030781:Organisms, Genetically Modified / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity
chemical_list: D018076:DNA, Complementary; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins