The insect group ll chitinase(ChtIl,also known as Cht10)is a unique chitinasewith multiple catalytic and chitin-binding domains.It has been proven genetically to be anessential chitinase for molting.However,Chtll'...The insect group ll chitinase(ChtIl,also known as Cht10)is a unique chitinasewith multiple catalytic and chitin-binding domains.It has been proven genetically to be anessential chitinase for molting.However,Chtll's role in chitin degradation during insectdevelopment remains poorly understood.Obtaining this knowledge is the key to fullyunderstanding the chitin degradation system in insects.Here,we investigated the roleof OfChtll during the molting of Ostrinia furnacalis,a model lepidopteran pest insect.OfChtll was expressed earlier than OfChtI(OfCht5)and OfChi-h,at both the gene andprotein levels during larva-pupa molting as evidenced by quantitative polymerase chainreaction and western blot analyses.A truncated OfChtII,OfChtII-B4C1,was recombinantlyexpressed in Pichia pastoris cells and purified to homogeneity.The recombinant OfChtll-B4C1 loosened compacted chitin particles and produced holes in the cuticle surface asevidenced by scanning electron microscopy.It synergized with OfChtl and OfChi-h whenhydrolyzing insoluble a-chitin.These findings suggested an important role for ChtIl duringinsect molting and also provided a strategy for the coordinatdd degradation of cuticularchitin during insect molting by Chtll,Chtl and Chi-h.展开更多
基金the National Key R&D Program of China(2017YFD0201207)Natural Science Foundation of China(31402015,31830076)+1 种基金the Open Research Project from State Key Laboratory for Biology of Plant Diseases and Insect Pests(SKLOF201801)the Shenzhen Science and Technology Program(KQTD20180411143628272).
文摘The insect group ll chitinase(ChtIl,also known as Cht10)is a unique chitinasewith multiple catalytic and chitin-binding domains.It has been proven genetically to be anessential chitinase for molting.However,Chtll's role in chitin degradation during insectdevelopment remains poorly understood.Obtaining this knowledge is the key to fullyunderstanding the chitin degradation system in insects.Here,we investigated the roleof OfChtll during the molting of Ostrinia furnacalis,a model lepidopteran pest insect.OfChtll was expressed earlier than OfChtI(OfCht5)and OfChi-h,at both the gene andprotein levels during larva-pupa molting as evidenced by quantitative polymerase chainreaction and western blot analyses.A truncated OfChtII,OfChtII-B4C1,was recombinantlyexpressed in Pichia pastoris cells and purified to homogeneity.The recombinant OfChtll-B4C1 loosened compacted chitin particles and produced holes in the cuticle surface asevidenced by scanning electron microscopy.It synergized with OfChtl and OfChi-h whenhydrolyzing insoluble a-chitin.These findings suggested an important role for ChtIl duringinsect molting and also provided a strategy for the coordinatdd degradation of cuticularchitin during insect molting by Chtll,Chtl and Chi-h.
