title: Effect of BBX-B8 overexpression on development, body weight, silk protein synthesis and egg diapause of Bombyx mori.
abstract: Bombyxin (BBX) is an insulin-like peptide exists in the silkworm Bombyx mori. Our previous studies on the effects of inhibiting BBX-B8 expression found that BBX-B8 is important for the development of organ, reproduction and trehalose metabolism in the silkworms. In this paper, we investigated the expression profile of the BBX-B8 gene and effect of BBX-B8 overexpression on the development, body weight, silk protein synthesis and egg diapause of B. mori to further understand BBX-B8 functions. BBX-B8 gene expression could be detected in the brains, midguts, anterior silkglands, ovaries, testes, fat bodies, hemolymph, malpighian tubules and embryos by RT-PCR, however it was mainly expressed in the brain. Western blots showed that the change in BBX-B8 expression was not obvious in the brain of 1- to 4-day-old larvae of fifth instar silkworms, but expression increased substantially at 5- to 6-day-old larvae of fifth instar silkworms. Transgenic silkworms overexpressing BBX-B8 were obtained by introducing non-transposon transgenic vector pIZT-B8 containing a BBX-B8 gene driven by Orgyia pseudotsugata nucleopolyhedrovirus IE2 promoter into the genome. Development duration of the transgenic silkworms was delayed by 2.5-3.5 days. Cocoon shell weight of transgenic silkworms was reduced by 4.79 % in females and 7.44 % in males, pupal weight of transgenic silkworms was reduced 6.75 % in females and 13.83 % in males compared to non-transgenic silkworms, and 5.56-14.29 % of transgenic moths laid nondiapausing eggs. All results indicated that BBX-B8 plays an important role in the development, silk protein synthesis and egg diapause of silkworm.
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Zheng
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Yongchang
authors.initials: Y
authors.lastname: Gong
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Kumar
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Sulan
authors.initials: S
authors.lastname: Kuan
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Liang
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.|National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, 215123, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Hu
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.|National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, 215123, China.
authors.forename: Guangli
authors.initials: G
authors.lastname: Cao
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China.|National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, 215123, China.
authors.forename: Renyu
authors.initials: R
authors.lastname: Xue
authors.affiliation: School of Biology and Basic Medical Science, Soochow University, Suzhou, 215123, China. gongcl@suda.edu.cn.|National Engineering Laboratory for Modern Silk, Soochow University, Suzhou, 215123, China. gongcl@suda.edu.cn.|Pre-clinical Medical and Biological Science College, Soochow University, No. 199 Ren-ai Road, Suzhou, Jiangsu, China. gongcl@suda.edu.cn.
authors.forename: Chengliang
authors.initials: C
authors.lastname: Gong
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics*; D001835:Body Weight / Q000235:genetics; D012831:Bombyx / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D000074767:Diapause / Q000235:genetics*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D007814:Larva; D008297:Male; D009479:Neuropeptides / Q000235:genetics*; D011401:Promoter Regions, Genetic; D047011:Silk / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D009479:Neuropeptides; D047011:Silk; C075028:bombyxins
keywords: BBX-8 gene; Bombyxin; Development; Egg diapause; Silk protein synthesis