Structures and homology modeling of chicken major histocompatibility complex protein class I (BF2 and beta2m).
In order to elucidate the two-dimensional (2D) and three-dimensional (3D) structures of chicken major histocompatibility complex (MHC) class I protein (BF2 and beta2m) and further reconstruct their complex identifying the virus-derived antigenic peptides, the mature protein of BF2 and beta2m genes were expressed solubility in pMAL-p2X/Escherichia coli. TB1 system. The expressed MBP-BF2- and MBP-beta2m-fusion proteins were purified, and cleaved by the factor Xa protease. Subsequently, the monomers were further separated, and the purified MBP-BF2, -beta2m, and MBP were analyzed by circular dichroism (CD) spectrum. The contents of alpha-helix, beta-sheet, turn, and random coil in BF2 protein were 72, 102, 70, and 90 amino acids (aa), respectively. The beta2m proteins displayed a typical beta-sheet and the contents of alpha-helix, beta-sheet, turn, and random coil were 0, 46, 30, and 22 aa, respectively. Homology modeling of BF2 and beta2m proteins were similar as the 3D structure of human MHC class I (HLA-A2). The results showed that pMAL-p2X expression and purification system could be used to obtain the right conformational BF2 and beta2m proteins, and the 2D and 3D structures of BF2 and beta2m were revealed to be similar to human's. The recombinant BF2 and beta2m-based proteins might be a powerful tool for further detecting antigenic peptides.
Yan
Ruo Qian
RQ
Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094, China.
Li
Xin Sheng
XS
Yang
Tian Yao
TY
Xia
Chun
C
D000818:Animals; D015153:Blotting, Western; D002645:Chickens / Q000235:genetics / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D008285:Major Histocompatibility Complex / Q000235:genetics; D008958:Models, Molecular; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D012995:Solubility; D040681:Structural Homology, Protein
D015395:Histocompatibility Antigens Class I; D011994:Recombinant Proteins