LIME: a new membrane Raft-associated adaptor protein involved in CD4 and CD8 coreceptor signaling.
Lymphocyte membrane rafts contain molecules critical for immunoreceptor signaling. Here, we report identification of a new raft-associated adaptor protein LIME (Lck-interacting molecule) expressed predominantly in T lymphocytes. LIME becomes tyrosine phosphorylated after cross-linking of the CD4 or CD8 coreceptors. Phospho-LIME associates with the Src family kinase Lck and its negative regulator, Csk. Ectopic expression of LIME in Jurkat T cells results in an increase of Csk in lipid rafts, increased phosphorylation of Lck and higher Ca2+ response to CD3 stimulation. Thus, LIME appears to be involved in regulation of T cell activation by coreceptors.
Brdicková
Nadezda
N
Institute of Molecular Genetics, AS CR, Vídenská 1083, 142 20 Praha 4, Czech Republic.
Brdicka
Tomás
T
Angelisová
Pavla
P
Horváth
Ondrej
O
Spicka
Jiri
J
Hilgert
Ivan
I
Paces
Jan
J
Simeoni
Luca
L
Kliche
Stefanie
S
Merten
Camilla
C
Schraven
Burkhart
B
Horejsí
Václav
V
D033942:Adaptor Proteins, Vesicular Transport / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000595:Amino Acid Sequence; D015704:CD4 Antigens / Q000276:immunology*; D016827:CD8 Antigens / Q000276:immunology*; D000081247:CSK Tyrosine-Protein Kinase; D018076:DNA, Complementary; D030562:Databases, Protein; D006801:Humans; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000378:metabolism; D021962:Membrane Microdomains / Q000276:immunology*; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D019061:src-Family Kinases
D033942:Adaptor Proteins, Vesicular Transport; D015704:CD4 Antigens; D016827:CD8 Antigens; D018076:DNA, Complementary; C480489:Lck-interacting protein, mouse; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D019061:src-Family Kinases; C000631346:CSK protein, human