|
|
|
|
|
|
|
||
By
From Bristol-Myers Squibb Pharmaceutical Research Institute, Seattle, Washington 98121
The interaction of Fas (CD95), a member of the tumor necrosis factor receptor (TNFR) family, and its ligand (FasL) triggers programmed cell death (apoptosis) and is involved in the regulation of immune responses. Although the Fas-FasL interaction is conserved across species barriers, little is currently known about the molecular details of this interaction. Our aim was to
identify residues in Fas that are important for ligand binding. With the aid of a Fas molecular
model, candidate amino acid residues were selected in the Fas extracellular domain 2 (D2) and
D3 and subjected to serine-scanning mutagenesis to produce mutant Fas molecules in the form
of Ig fusion proteins. The effects of these mutations on FasL binding was examined by measuring the ability of these proteins to inhibit FasL-mediated apoptosis of Jurkat cells and bind FasL
in ELISA and BIAcoreTM assays. Mutation of two amino acids, R86 and R87 (D2), to serine
totally abolished the ability of Fas to interact with its ligand, whereas mutants K84S, L90S, E93S (D2), or H126S (D3) showed reduced binding compared with wild-type Fas. Two mutants (K78S and H95S) bound FasL comparably to wild type. Therefore, the binding of FasL
involves residues in two domains that correspond to positions critical for ligand binding in
other family members (TNFR and CD40) but are conserved between murine and human Fas.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
| TABLE OF CONTENTS |
|
