A small region of porcine hemagglutinating encephalomyelitis virus spike protein interacts with the neural cell adhesion molecule.
OBJECTIVE
The spike (S) protein of porcine hemagglutinating encephalomyelitis virus (PHEV) may mediate infection by binding to a cellular neural cell adhesion molecule (NCAM). This study aimed to identify the crucial domain of the S1 subunit of the S protein that interacts with NCAM.


METHODS
Three truncated segments (S(1-291), S(277-794) and S(548-868)) of the S gene of PHEV and the NCAM gene were cloned individually into the Escherichia coli expression vectors and yeast two-hybrid expression vectors. The interaction between S(1-291), S(277-794), S(548-868) and NCAM were detected by a GST pull-down experiment and yeast two-hybrid assay.


RESULTS
Three fusion proteins (S(1-291), S(277-794) and S(548-868)) were screened for their interactions with NCAM by protein-protein interaction assays. The results of these assays clarified that S(277-794) interacted with NCAM, while S(1-291) and S(548-868) did not.


CONCLUSIONS
A small fragment (258-amino-acid fragment, residues 291-548) on the PHEV S protein was posited to be the minimum number of amino acids necessary to interact with NCAM. This fragment may be the receptor-binding domain that mediates PHEV binding to NCAM.
Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.
Bo
B
Dong
Wei
W
Gao
Huijun
H
Lu
Kui
K
Zhao
Ning
N
Ding
Wenfeng
W
Liu
Jiakuan
J
Zhao
Yungang
Y
Lan
Bo
B
Tang
Zhao
Z
Jin
Wenqi
W
He
Feng
F
Gao
D000595:Amino Acid Sequence; D000596:Amino Acids; D017934:Coronavirus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D019006:Neural Cell Adhesion Molecules / Q000378:metabolism*; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D064370:Spike Glycoprotein, Coronavirus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D000596:Amino Acids; D019006:Neural Cell Adhesion Molecules; D011993:Recombinant Fusion Proteins; D064370:Spike Glycoprotein, Coronavirus