TY - JOUR
T1 - Analysis of an orf virus chemokine-binding protein
T2 - Shifting ligand specificities among a family of poxvirus viroceptors
AU - Seet, Bruce T.
AU - McCaughan, Catherine A.
AU - Handel, Tracy M.
AU - Mercer, Andrew
AU - Brunetti, Craig
AU - McFadden, Grant
AU - Fleming, Stephen B.
PY - 2003/12/9
Y1 - 2003/12/9
N2 - We identify a secreted chemokine inhibitor encoded by orf virus (ORFV), the prototypic poxvirus of the Parapoxvirus genus, and show that it is related to the poxvirus type II CC-chemokine-binding proteins (CBP-II) produced by members of the Orthopoxvirus and Leporipoxvirus genera. The ORFV chemokine-binding protein (CBP) is functionally similar to the CBP-II proteins in its ability to bind and inhibit many CC-chemokines with high affinity. However, unlike CBP-II, the ORFV CBP also binds with high affinity to lymphotactin, a member of the C-chemokine family, demonstrating that the ORFV CBP possesses an altered binding specificity. Interestingly, the amino acid sequence of ORFV CBP more closely resembles the granulocyte-macrophage colony-stimulating factor/IL-2 inhibitory factor also produced by ORFV, implicating the granulocyte-macrophage colony-stimulating factor/IL-2 inhibitory factor protein as a highly diverged, but related, member of the CBP-II protein family. Notably, these findings suggest that the genes that encode these proteins derive from a common poxvirus ancestral gene that has since been modified in binding specificity during speciation of the poxvirus genera. Overall, these findings illustrate the concept of evolution of viral proteins at the biophysical and molecular interface.
AB - We identify a secreted chemokine inhibitor encoded by orf virus (ORFV), the prototypic poxvirus of the Parapoxvirus genus, and show that it is related to the poxvirus type II CC-chemokine-binding proteins (CBP-II) produced by members of the Orthopoxvirus and Leporipoxvirus genera. The ORFV chemokine-binding protein (CBP) is functionally similar to the CBP-II proteins in its ability to bind and inhibit many CC-chemokines with high affinity. However, unlike CBP-II, the ORFV CBP also binds with high affinity to lymphotactin, a member of the C-chemokine family, demonstrating that the ORFV CBP possesses an altered binding specificity. Interestingly, the amino acid sequence of ORFV CBP more closely resembles the granulocyte-macrophage colony-stimulating factor/IL-2 inhibitory factor also produced by ORFV, implicating the granulocyte-macrophage colony-stimulating factor/IL-2 inhibitory factor protein as a highly diverged, but related, member of the CBP-II protein family. Notably, these findings suggest that the genes that encode these proteins derive from a common poxvirus ancestral gene that has since been modified in binding specificity during speciation of the poxvirus genera. Overall, these findings illustrate the concept of evolution of viral proteins at the biophysical and molecular interface.
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U2 - 10.1073/pnas.2336648100
DO - 10.1073/pnas.2336648100
M3 - Article
C2 - 14657392
AN - SCOPUS:0345598122
SN - 0027-8424
VL - 100
SP - 15137
EP - 15142
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 25
ER -