Identification and characterization of a novel peritrophic matrix protein, Ae-Aper50, and the microvillar membrane protein, AEG12, from the mosquito, Aedes aegypti
- 作者：Shao ; Li ; Devenport ; Martin ; Fujioka ; Hisashi ; Ghosh ; Anil ; Jacobs-Lorena ; Marcelo
- 关键词：Mosquito ; Aedes aegypti ; Midgut ; Microvilli ; Peritrophic matrix
- 刊名：Insect Biochemistry and Molecular Biology
- 出版年：2005
- 期刊代码：80_09651748
- 类别：bio
- 出版时间：September, 2005
- 卷：35
- 期：9
- 页码：947-959
- 文件大小：469 K
摘要
Immuno-screening of an adult Aedes aegypti midgut cDNA expression library with anti-peritrophic matrix antibodies identified cDNAs encoding a novel peritrophic matrix protein, termed Ae. aegypti Adult Peritrophin 50 (Ae-Aper50), and the epithelial cell-surface membrane protein, AEG12. Both genes are expressed exclusively in the midguts of adult female mosquitoes and their expression is strongly induced by blood feeding. Ae-Aper50 has a predicted secretory signal peptide and five chitin-binding domains with intervening mucin-like domains. Localization of Ae-Aper50 to the peritrophic matrix was demonstrated by immuno-electron microscopy. Recombinant Ae-Aper50 expressed in baculovirus-infected insect cells binds chitin in vitro. Site-directed mutagenesis was used to study the role that cysteine residues from a single chitin-binding domain play in the binding to a chitin substrate. Most of the cysteine residues proved to be critical for binding. AEG12 has a putative secretory signal peptide at the amino-terminus and a putative glycosyl-phosphatidylinositol (GPI) anchor signal at its carboxyl-terminus and the protein was localized by immuno-electron microscopy to the midgut epithelial cell microvilli.