Targeting of MIST to Src-family kinases via SKAP55-SLAP-130 adaptor complex in mast cells.
MIST (mast cell immunoreceptor signal transducer; also termed Clnk) is an adaptor protein structurally related to SLP-76-family hematopoietic cell-specific adaptor proteins. We demonstrate here that two major MIST-associated phosphoproteins expressed in mast cell lines are SLAP-130 and SKAP55, adaptors known to interact with the Src-homology (SH) 2 domain of Src-family protein tyrosine kinases (PTKs). MIST directly associated with SLAP-130 via its SH2 domain, and collaboration of SLAP-130 with SKAP55 was required for the recruitment of MIST to Lyn. Furthermore, MIST was preferentially recruited to Fyn rather than Lyn, which is regulated by higher affinity binding of SLAP-130 and SKAP55 with the Fyn-SH2 domain than the Lyn-SH2 domain. Our results suggest that the MIST-SLAP-130-SKAP55 adaptor complex functions downstream of high-affinity IgE receptor-associated Src-PTKs in mast cells.
Fujii
Yasuyuki
Y
Department of Molecular Biology Laboratory, Medicinal Research Laboratories, Taisho Pharmaceutical Co Ltd, 1-403 Yoshino-cho, Saitama-shi, Saitama 330-8530, Japan.
Wakahara
Shunichi
S
Nakao
Toru
T
Hara
Toshifumi
T
Ohtake
Hidenori
H
Komurasaki
Toshi
T
Kitamura
Kunihiro
K
Tatsuno
Akiko
A
Fujiwara
Naruyoshi
N
Hozumi
Nobumichi
N
Ra
Chisei
C
Kitamura
Daisuke
D
Goitsuka
Ryo
R
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008407:Mast Cells / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D017386:Sequence Homology, Amino Acid; D019061:src-Family Kinases / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; C411024:CLNK protein, human; D002352:Carrier Proteins; C106957:FYB1 protein, human; C491468:Fyb protein, mouse; D010750:Phosphoproteins; C108336:SKAP1 protein, human; C491559:Skap1 protein, rat; D019061:src-Family Kinases