TY - JOUR
T1 - Paramyxovirus fusion (F) protein
T2 - A conformational change on cleavage activation
AU - Dutch, Rebecca Ellis
AU - Hagglund, Ryan N.
AU - Nagel, Margaret A.
AU - Paterson, Reay G.
AU - Lamb, Robert A.
N1 - Funding Information:
This work was supported in part by Research Grant AI-23173 from the National Institute of Allergy and Infectious Disease. R.E.D. was supported in part by a Public Health Service NRSA F32 AI-09607. Part of this work was performed by R.N.H. toward an undergraduate Honors Thesis (1999) at Northwestern University. R.A.L. is an Investigator of the Howard Hughes Medical Institute.
PY - 2001/3/1
Y1 - 2001/3/1
N2 - The fusion (F) protein of the paramyxovirus SV5 promotes both virus-cell and cell-cell fusion. Recently, the atomic structure at 1.4 Å of an extremely thermostable six-helix bundle core complex consisting of two heptad repeat regions of the F protein has been described (K. A. Baker, R. E. Dutch, R. A. Lamb, and T. S. Jardetsky, Mol. Cell 3, 309-319, 1999). To analyze the conformations of the F protein at various stages of the membrane fusion process and to understand further the role of formation of the six-helix bundle core complex in promotion of membrane fusion, antibodies to peptides corresponding to regions of the F protein were obtained. Major changes in F protein antibody recognition were found after cleavage of the precursor protein F0 to the fusogenically active disulfide-linked heterodimer, F1 + F2, and antibodies directed against the heptad repeat regions recognized only the uncleaved form. A monoclonal antibody directed against the F protein showed increased recognition at the cell surface of the cleaved form of the F protein as compared to uncleaved F protein, again indicating changes in conformation between the uncleaved and cleaved forms of the F protein. Anti-peptide antibodies specific for the heptad repeat regions were unable to precipitate a synthetic protein that consisted of the heptad repeat regions separated only by a small spacer, suggesting that the antibodies are unable to recognize their target regions when the heptad repeats are present in the six-helix bundle core complex. Taken together, these data indicate that the six-helix bundle core complex is not present in the precursor molecule F0 and that significant conformational changes occur subsequent to cleavage of the F protein.
AB - The fusion (F) protein of the paramyxovirus SV5 promotes both virus-cell and cell-cell fusion. Recently, the atomic structure at 1.4 Å of an extremely thermostable six-helix bundle core complex consisting of two heptad repeat regions of the F protein has been described (K. A. Baker, R. E. Dutch, R. A. Lamb, and T. S. Jardetsky, Mol. Cell 3, 309-319, 1999). To analyze the conformations of the F protein at various stages of the membrane fusion process and to understand further the role of formation of the six-helix bundle core complex in promotion of membrane fusion, antibodies to peptides corresponding to regions of the F protein were obtained. Major changes in F protein antibody recognition were found after cleavage of the precursor protein F0 to the fusogenically active disulfide-linked heterodimer, F1 + F2, and antibodies directed against the heptad repeat regions recognized only the uncleaved form. A monoclonal antibody directed against the F protein showed increased recognition at the cell surface of the cleaved form of the F protein as compared to uncleaved F protein, again indicating changes in conformation between the uncleaved and cleaved forms of the F protein. Anti-peptide antibodies specific for the heptad repeat regions were unable to precipitate a synthetic protein that consisted of the heptad repeat regions separated only by a small spacer, suggesting that the antibodies are unable to recognize their target regions when the heptad repeats are present in the six-helix bundle core complex. Taken together, these data indicate that the six-helix bundle core complex is not present in the precursor molecule F0 and that significant conformational changes occur subsequent to cleavage of the F protein.
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U2 - 10.1006/viro.2000.0817
DO - 10.1006/viro.2000.0817
M3 - Article
C2 - 11222104
AN - SCOPUS:0035264638
VL - 281
SP - 138
EP - 150
JO - Virology
JF - Virology
SN - 0042-6822
IS - 1
ER -