Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.


Logo for

PNAS 104 (16): 6638-6643

Copyright © 2007 by the National Academy of Sciences.


SLP-76 mediates and maintains activation of the Tec family kinase ITK via the T cell antigen receptor-induced association between SLP-76 and ITK

Yaron Bogin, Carmit Ainey, Dvora Beach, and Deborah Yablonski*

The Rappaport Family Institute for Research in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, P.O. Box 9649, Bat Galim, Haifa 31096, Israel

Edited by Arthur Weiss, University of California, San Francisco School of Medicine, San Francisco, CA, and approved February 21, 2007

Received for publication November 5, 2006.

Abstract: ITK (IL-2-inducible T cell kinase), a Tec family protein tyrosine kinase (PTK), is one of three PTKs required for T cell antigen receptor (TCR)-induced activation of phospholipase C-{gamma}1 (PLC-{gamma}1). Like Src and Abl family PTKs, ITK adopts an inactive, "closed" conformation, and its conversion to the active conformation is not well understood, nor have its direct substrates been identified. In a side-by-side comparison of ITK and ZAP-70 ({zeta} chain-associated protein kinase of 70 kDa), ITK efficiently phosphorylated Y783 and Y775 of PLC-{gamma}1, two phosphorylation sites that are critical for its activation, whereas ZAP-70 did not. SLP-76 (SH2-domain-containing leukocyte protein of 76 kDa), an adaptor required for TCR-induced activation of PLC-{gamma}1, was required for the phosphorylation of both PLC-{gamma}1 sites in intact cells. Furthermore, this event depended on the N-terminal tyrosines of SLP-76. Likewise, SLP-76, particularly its N-terminal tyrosines, was required for TCR-induced tyrosine phosphorylation and activation of ITK but was not required for the phosphorylation or activation of ZAP-70. Both ZAP-70 and ITK phosphorylated SLP-76 in vitro; thus, both PTKs are potential regulators of SLP-76, but only ITK is regulated by SLP-76. Upon TCR stimulation, a small fraction of ITK bound to SLP-76. This fraction, however, encompassed most of the catalytically active ITK. Catalytic activity was lost upon mild elution of ITK from the SLP-76-nucleated complex but was restored upon reconstitution of the complex. We propose that SLP-76 is required for ITK activation; furthermore, an ongoing physical interaction between SLP-76 and ITK is required to maintain ITK in an active conformation.

Key Words: adaptor protein • kinase regulation • phospholipase C-{gamma} • signal transduction

Author contributions: Y.B. and D.Y. designed research; Y.B. and D.B. performed research; C.A. contributed new reagents/analytic tools; Y.B. and D.Y. analyzed data; and Y.B. and D.Y. wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

*To whom correspondence should be addressed. E-mail: debya{at}

© 2007 by The National Academy of Sciences of the USA

Role of Itk signalling in the interaction between influenza A virus and T-cells.
K. Fan, Y. Jia, S. Wang, H. Li, D. Wu, G. Wang, and J.-L. Chen (2012)
J. Gen. Virol. 93, 987-997
   Abstract »    Full Text »    PDF »
Itk Controls the Spatiotemporal Organization of T Cell Activation.
K. L. Singleton, M. Gosh, R. D. Dandekar, B. B. Au-Yeung, O. Ksionda, V. L. J. Tybulewicz, A. Altman, D. J. Fowell, and C. Wulfing (2011)
Science Signaling 4, ra66
   Abstract »    Full Text »    PDF »
Sequential phosphorylation of SLP-76 at tyrosine 173 is required for activation of T and mast cells.
M. Sela, Y. Bogin, D. Beach, T. Oellerich, J. Lehne, J. E. Smith-Garvin, M. Okumura, E. Starosvetsky, R. Kosoff, E. Libman, et al. (2011)
EMBO J. 30, 3160-3172
   Abstract »    Full Text »    PDF »
Requirements for Eomesodermin and Promyelocytic Leukemia Zinc Finger in the Development of Innate-Like CD8+ T Cells.
S. M. Gordon, S. A. Carty, J. S. Kim, T. Zou, J. Smith-Garvin, E. S. Alonzo, E. Haimm, D. B. Sant'Angelo, G. A. Koretzky, S. L. Reiner, et al. (2011)
J. Immunol. 186, 4573-4578
   Abstract »    Full Text »    PDF »
Vav1-Mediated Scaffolding Interactions Stabilize SLP-76 Microclusters and Contribute to Antigen-Dependent T Cell Responses.
N. R. Sylvain, K. Nguyen, and S. C. Bunnell (2011)
Science Signaling 4, ra14
   Abstract »    Full Text »    PDF »
T-cell receptor signals direct the composition and function of the memory CD8+ T-cell pool.
J. E. Smith-Garvin, J. C. Burns, M. Gohil, T. Zou, J. S. Kim, J. S. Maltzman, E. J. Wherry, G. A. Koretzky, and M. S. Jordan (2010)
Blood 116, 5548-5559
   Abstract »    Full Text »    PDF »
In Vivo Significance of ITK-SLP-76 Interaction in Cytokine Production.
J. A. Grasis, D. M. Guimond, N. R. Cam, K. Herman, P. Magotti, J. D. Lambris, and C. D. Tsoukas (2010)
Mol. Cell. Biol. 30, 3596-3609
   Abstract »    Full Text »    PDF »
T-Cell Signaling Regulated by the Tec Family Kinase, Itk.
A. H. Andreotti, P. L. Schwartzberg, R. E. Joseph, and L. J. Berg (2010)
Cold Spring Harb Perspect Biol 2, a002287
   Abstract »    Full Text »    PDF »
Hematopoietic Lineage Cell-Specific Protein 1 Is Recruited to the Immunological Synapse by IL-2-Inducible T Cell Kinase and Regulates Phospholipase C{gamma}1 Microcluster Dynamics during T Cell Spreading.
E. Carrizosa, T. S. Gomez, C. M. Labno, D. A. Klos Dehring, X. Liu, B. D. Freedman, D. D. Billadeau, and J. K. Burkhardt (2009)
J. Immunol. 183, 7352-7361
   Abstract »    Full Text »    PDF »
The Lymphoma-associated Fusion Tyrosine Kinase ITK-SYK Requires Pleckstrin Homology Domain-mediated Membrane Localization for Activation and Cellular Transformation.
S. Rigby, Y. Huang, B. Streubel, A. Chott, M.-Q. Du, S. D. Turner, and C. M. Bacon (2009)
J. Biol. Chem. 284, 26871-26881
   Abstract »    Full Text »    PDF »
The importance of Src homology 2 domain-containing leukocyte phosphoprotein of 76 kilodaltons sterile-{alpha} motif domain in thymic selection and T-cell activation.
S. Shen, J. Lau, M. Zhu, J. Zou, D. Fuller, Q.-j. Li, and W. Zhang (2009)
Blood 114, 74-84
   Abstract »    Full Text »    PDF »
Cbl Enforces an SLP76-dependent Signaling Pathway for T Cell Differentiation.
Y. J. Chiang, M. S. Jordan, R. Horai, P. L. Schwartzberg, G. A. Koretzky, and R. J. Hodes (2009)
J. Biol. Chem. 284, 4429-4438
   Abstract »    Full Text »    PDF »
Origin of the sharp boundary that discriminates positive and negative selection of thymocytes.
A. Prasad, J. Zikherman, J. Das, J. P. Roose, A. Weiss, and A. K. Chakraborty (2009)
PNAS 106, 528-533
   Abstract »    Full Text »    PDF »
Requirements of SLP76 tyrosines in ITAM and integrin receptor signaling and in platelet function in vivo.
N. A. Bezman, L. Lian, C. S. Abrams, L. F. Brass, M. L. Kahn, M. S. Jordan, and G. A. Koretzky (2008)
J. Exp. Med. 205, 1775-1788
   Abstract »    Full Text »    PDF »
Inhibition of ZAP-70 Kinase Activity via an Analog-sensitive Allele Blocks T Cell Receptor and CD28 Superagonist Signaling.
S. E. Levin, C. Zhang, T. A. Kadlecek, K. M. Shokat, and A. Weiss (2008)
J. Biol. Chem. 283, 15419-15430
   Abstract »    Full Text »    PDF »
The kinase Syk as an adaptor controlling sustained calcium signalling and B-cell development.
Y. Kulathu, E. Hobeika, G. Turchinovich, and M. Reth (2008)
EMBO J. 27, 1333-1344
   Abstract »    Full Text »    PDF »
Selective targeting of ITK blocks multiple steps of HIV replication.
J. A. Readinger, G. M. Schiralli, J.-K. Jiang, C. J. Thomas, A. August, A. J. Henderson, and P. L. Schwartzberg (2008)
PNAS 105, 6684-6689
   Abstract »    Full Text »    PDF »
Keeping the (Kinase) Party Going: SLP-76 and ITK Dance to the Beat.
Q. Qi and A. August (2007)
Sci. STKE 2007, pe39
   Abstract »    Full Text »    PDF »

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882