title: Cathepsin B-like proteinase is involved in the decomposition of the adult fat body of Helicoverpa armigera.
abstract: Cathepsin B-like proteinase (HCB, EC 3.4.22.1) is expressed in Helicoverpa armigera oocytes and adult fat bodies. Previous work has revealed that HCB plays a key role in the degradation of yolk proteins during embryogenesis. This study investigated the function and regulatory activation of HCB in adult fat bodies during aging and oogenesis. The HCB transcript was detected at all stages from larval to adult fat bodies with Northern blot analysis. Pro-HCB was also detected in fat bodies at these stages with an immunoblot assay using a monoclonal antibody against HCB. However, mature HCB and its activity were only detected in fat bodies of pre-adults and adults. This evidence suggested that HCB is regulated post-translationally by activation of the pro-enzyme during the pupa-adult metamorphosis. The activation of HCB was coupled with the expression of hormone receptor 3 (HHR3), and was up-regulated by the ecdysteroid agonist, RH-2485, suggesting that HCB activation is related to the ecdysone regulatory system. The decomposition of the adult fat bodies during aging and oogenesis was found to occur via programmed cell death, in which HCB took part.
authors.affiliation: School of Life Sciences, Shandong University, Jinan, China.
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Yang
authors.forename: Li-Jing
authors.initials: LJ
authors.lastname: Hou
authors.forename: Du-Juan
authors.initials: DJ
authors.lastname: Dong
authors.forename: Hong-Lian
authors.initials: HL
authors.lastname: Shao
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Wang
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002401:Cathepsin B / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005216:Fat Body / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006834:Hydrazines / Q000494:pharmacology; D007605:Juvenile Hormones / Q000494:pharmacology; D009036:Moths / Q000201:enzymology / Q000378:metabolism*; D010063:Ovum
chemical_list: D004791:Enzyme Inhibitors; D006834:Hydrazines; D007605:Juvenile Hormones; C406712:methoxyfenozide; D002401:Cathepsin B