title: Role of BmDredd during Apoptosis of Silk Gland in Silkworm, Bombyx mori.
abstract: Silk glands (SGs) undergo massive apoptosis driven degeneration during the larval-pupal transformation. To better understand this event on molecular level, we investigated the expression of apoptosis-related genes across the developmental transition period that spans day 4 in the fifth instar Bombyx mori larvae to day 2 pupae. Increases in the expression of BmDredd (an initiator caspase homolog) closely followed the highest BmEcR expression and resembled the expression trend of BmIcE. Simultaneously, we found that BmDredd expression was significantly higher in SG compared to other tissues at 18 h post-spinning, but reduced following injection of the apoptosis inhibitor (Z-DEVD-fmk). Furthermore, BmDredd expression correlated with changes of caspase3-like activities in SG and RNAi-mediated knockdown of BmDredd delayed SG apoptosis. Moreover, caspase3-like activity was increased in SG by overexpression of BmDredd. Taken together, the results suggest that BmDredd plays a critical role in SG apoptosis.
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Rui-Ting
authors.initials: RT
authors.lastname: Chen
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Peng
authors.initials: P
authors.lastname: Jiao
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Hu-Hu
authors.initials: HH
authors.lastname: Xin
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Deng-Pan
authors.initials: DP
authors.lastname: Zhang
authors.affiliation: Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: Yun-Gen
authors.initials: YG
authors.lastname: Miao
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D012831:Bombyx / Q000502:physiology*; D061945:Caspase Inhibitors / Q000494:pharmacology; D020169:Caspases / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008675:Metamorphosis, Biological; D047011:Silk / Q000378:metabolism*
chemical_list: D061945:Caspase Inhibitors; D019476:Insect Proteins; D047011:Silk; D020169:Caspases