Cutting edge: KAP10, a novel transmembrane adapter protein genetically linked to DAP12 but with unique signaling properties.
Transmembrane adapter proteins are a class of molecules that mediate signals from an extracellular receptor to the cytoplasm of the cell. We have cloned a novel transmembrane adapter protein called KAP10, a approximately 10-kDa protein that is encoded within 100 bp of the DAP12 locus on human chromosome 19. KAP10 is predominantly expressed in immune cells, including NK cells, T cells, and monocytes. We show that KAP10, unlike other transmembrane adapter proteins, binds phosphatidylinositol-3 kinase following phosphorylation of a cytoplasmic YINM motif, which results in activation of Akt. In addition, we identify KAP10 as being able to bind the adapter protein Grb2. Based on our data, we suggest that this molecule is involved in stimulation and costimulation in cells of both myeloid and lymphoid origin.
Chang
C
C
Division of Immunology, Research Group in Human Reproductive Immunobiology, Department of Pathology, University of Cambridge, United Kingdom.
Dietrich
J
J
Harpur
A G
AG
Lindquist
J A
JA
Haude
A
A
Loke
Y W
YW
King
A
A
Colonna
M
M
Trowsdale
J
J
Wilson
M J
MJ
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015704:CD4 Antigens / Q000276:immunology; D002460:Cell Line; D019070:Cell Lineage / Q000235:genetics / Q000276:immunology; D004789:Enzyme Activation; D008040:Genetic Linkage / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D007106:Immune Sera / Q000378:metabolism; D019169:Jurkat Cells; D008221:Lymphoid Tissue / Q000166:cytology / Q000378:metabolism; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D011971:Receptors, Immunologic / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*; D020298:U937 Cells
D048868:Adaptor Proteins, Signal Transducing; D015704:CD4 Antigens; D007106:Immune Sera; D008565:Membrane Proteins; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D011971:Receptors, Immunologic; C120528:HCST protein, human; C492355:Hcst protein, mouse; C110546:TYROBP protein, human; C494918:AKT1 protein, human