Molecular characterization of a CD95 signaling mutant.
OBJECTIVE
To study the intracellular signaling events associated with ligation of the surface receptor CD95.


METHODS
A mutant clone of Jurkat T cells, DD3, which fails to transmit apoptotic signals through CD95, was selected for study. Surface expression of CD95 and the primary nucleotide sequence of CD95, as well as the functional effects of a mutant CD95 molecule found in DD3, were examined.


RESULTS
DD3, while exhibiting impaired ability to undergo apoptosis after CD95 ligation, retained the ability to die after ultraviolet light stimulation. A CD95 complementary DNA (cDNA) cloned from DD3 encoded a mutant transmembrane protein lacking the carboxy-terminal "death domain." Western blotting confirmed the presence of both wild-type and mutant CD95 protein in DD3. Transfection of the mutant CD95 cDNA into parental Jurkat cells conferred protection from CD95-mediated apoptosis.


CONCLUSIONS
A mutant CD95 receptor lacking the cytoplasmic "death domain" can interfere with wild-type receptor function in T cells.
Peterson
E J
EJ
University of Iowa, Iowa City 52242, USA.
Latinis
K M
KM
Koretzky
G A
GA
D017209:Apoptosis / Q000502:physiology* / Q000528:radiation effects; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D019169:Jurkat Cells / Q000502:physiology / Q000528:radiation effects; D009154:Mutation / Q000235:genetics*; D015398:Signal Transduction / Q000502:physiology*; D013601:T-Lymphocytes / Q000502:physiology* / Q000528:radiation effects; D014162:Transfection; D014466:Ultraviolet Rays; D019014:fas Receptor / Q000235:genetics* / Q000502:physiology*
D018076:DNA, Complementary; D019014:fas Receptor