TY - JOUR
T1 - Growth and stability of a cholesterol-independent Semliki Forest virus mutant in mosquitoes
AU - Ahn, Anna
AU - Schoepp, Randal J.
AU - Sternberg, David
AU - Kielian, Margaret
N1 - Funding Information:
We thank the members of the Kielian laboratory for their comments and critical reading of the manuscript. This work was supported by grants to M.K. from the American Cancer Society (RPG-93-013-05VM), the National Institutes of Health (GM57454), the Hirschl Charitable Trust, the Jack K. and Helen B. Lazar Fellowship in Cell Biology, and Cancer Center Core Support Grant NIH/NCI P30-CA13330.
PY - 1999/9/30
Y1 - 1999/9/30
N2 - Semliki Forest virus (SFV) is an enveloped alphavirus that is transmitted in the wild by mosquito vectors. In tissue culture cells, SFV requires cholesterol in the cell membrane both for virus membrane fusion and for the efficient exit of progeny virus from the cell. A previously isolated SFV mutant, srf-3, is strikingly less cholesterol-dependent for virus fusion, exit, and growth due to a single amine acid change in the E1 spike protein subunit, proline 226 to serine. Here we show that when mosquitoes were infected by intrathoracic injection at a range of virus multiplicities, the growth of srf-3 was significantly more rapid than that of wild-type virus, particularly at low multiplicity infection. The differential cholesterol requirements for wild-type and srf-3 infection were maintained during virus passage through mosquitoes. The presence or absence of cholesterol in the srf-3 virus membrane did not affect its infection properties in mosquitoes. Thus the srf-3 mutation causes a growth advantage in the tissues of the mosquito host.
AB - Semliki Forest virus (SFV) is an enveloped alphavirus that is transmitted in the wild by mosquito vectors. In tissue culture cells, SFV requires cholesterol in the cell membrane both for virus membrane fusion and for the efficient exit of progeny virus from the cell. A previously isolated SFV mutant, srf-3, is strikingly less cholesterol-dependent for virus fusion, exit, and growth due to a single amine acid change in the E1 spike protein subunit, proline 226 to serine. Here we show that when mosquitoes were infected by intrathoracic injection at a range of virus multiplicities, the growth of srf-3 was significantly more rapid than that of wild-type virus, particularly at low multiplicity infection. The differential cholesterol requirements for wild-type and srf-3 infection were maintained during virus passage through mosquitoes. The presence or absence of cholesterol in the srf-3 virus membrane did not affect its infection properties in mosquitoes. Thus the srf-3 mutation causes a growth advantage in the tissues of the mosquito host.
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U2 - 10.1006/viro.1999.9932
DO - 10.1006/viro.1999.9932
M3 - Article
C2 - 10502523
AN - SCOPUS:0033619166
SN - 0042-6822
VL - 262
SP - 452
EP - 456
JO - Virology
JF - Virology
IS - 2
ER -