Mechanism of Retrovirus Infection 
gain entry into the cell. Recently we completed 
experiments that identify the portion of the Mo- 
MuLV receptor that binds to the virus envelope. 
Now we are examining other mutant receptor 
proteins that have normal retrovirus binding but 
do not permit infection. These studies may iden- 
tify portions of the receptor protein that are im- 
portant for the fusion of the virus to the target 
cell, the step in infection that follows binding. 
We are also investigating the consequences of 
Mo-MuLV binding and infection on cationic 
amino acid transport. Our long-term goal is to 
understand the chemical basis of the Mo-MuLV- 
Rec- 1 interaction in sufficient molecular detail to 
design small molecules that can block virus bind- 
ing and prevent infection. 
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