title: Establishment of a specific cell death induction system in Bombyx mori by a transgene with the conserved apoptotic regulator, mouse Bcl-2-associated X protein (mouse Bax).
abstract: The induction of apoptosis in vivo is a useful tool for investigating the functions and importance of particular tissues. B-cell leukaemia/lymphoma 2-associated X protein (Bax) functions as a pro-apoptotic factor and induces apoptosis in several organisms. The Bax-mediated apoptotic system is widely conserved from Caenorhabditis elegans to humans. In order to establish a tissue-specific cell death system in the domestic silkworm, Bombyx mori, we constructed a transgenic silkworm that overexpressed mouse Bax (mBax) in particular tissues by the Gal4-upstream activation sequence system. We found that the expression of mBax induced specific cell death in the silk gland, fat body and sensory cells. Fragmentation of genomic DNA was observed in the fat body, which expressed mBax, thereby supporting apoptotic cell death in this tissue. Using this system, we also demonstrated that specific cell death in sensory cells attenuated the response to the sex pheromone bombykol. These results show that we successfully established a tissue-specific cell death system in vivo that enabled specific deficiencies in particular tissues. The inducible cell death system may provide useful means for industrial applications of the silkworm and possible utilization for other species.
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Sumitani
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, Komaba, Meguro-Ku, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sakurai
authors.affiliation: Division of Functional Biochemistry Department of Biochemistry, Jichi Medical University, Shimotsuke, Tochigi, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kasashima
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Uchino
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, Komaba, Meguro-Ku, Tokyo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kanzaki
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tamura
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sezutsu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017209:Apoptosis; D012831:Bombyx / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D005088:Exocrine Glands / Q000502:physiology; D005216:Fat Body / Q000378:metabolism; D005233:Fatty Alcohols / Q000494:pharmacology; D005260:Female; D007814:Larva / Q000254:growth & development; D008297:Male; D051379:Mice; D018034:Olfactory Receptor Neurons / Q000166:cytology / Q000187:drug effects; D018035:Receptors, Odorant / Q000235:genetics / Q000378:metabolism; D012724:Sex Attractants / Q000494:pharmacology; D019076:Transgenes; D051028:bcl-2-Associated X Protein / Q000235:genetics*
chemical_list: D005233:Fatty Alcohols; D018035:Receptors, Odorant; D012724:Sex Attractants; D051028:bcl-2-Associated X Protein; C006787:bombykol
keywords: Bax; Bcl-2 protein; Gal4-UAS; apoptosis; transgenic silkworm