title: Crystal structure of zebrafish complement 1qA globular domain.
abstract: C1q contains three globular domains (C1qgD) that are the key functional component of the classical complement system. C1qgD can interact with important immune molecules, including IgG and C-reactive protein (CRP) to form defense systems to protect animals. Here, the first non-mammalian structure, zebrafish C1qA globular domain (Dare-C1qAgD) was solved. Although the overall architecture of Dare-C1qAgD is similar to human C1qA, residues involved in C1qBgD, C1qCgD, and CRP binding are somewhat different while residues involved in IgG binding are not present in zebrafish. The structure gives insight into how human and fish C1qA evolved from an ancestral protein.
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Yuan
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Mansoor
authors.initials: M
authors.lastname: Tariq
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China. xiachun@cau.edu.cn.|Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People's Republic of China. xiachun@cau.edu.cn.
authors.forename: Chun
authors.initials: C
authors.lastname: Xia
mesh_terms: D000818:Animals; D003172:Complement C1 / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019143:Evolution, Molecular; D006801:Humans; D000072417:Protein Domains; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000737:chemistry*
chemical_list: D003172:Complement C1; D029961:Zebrafish Proteins
keywords: C1q globular domain; evolution; structure; zebrafish