RAPL, a Rap1-binding molecule that mediates Rap1-induced adhesion through spatial regulation of LFA-1

@article{Katagiri2003RAPLAR,
  title={RAPL, a Rap1-binding molecule that mediates Rap1-induced adhesion through spatial regulation of LFA-1},
  author={K. Katagiri and A. Maeda and M. Shimonaka and T. Kinashi},
  journal={Nature Immunology},
  year={2003},
  volume={4},
  pages={741-748}
}
The small GTPase Rap1 is a potent activator of leukocyte integrin. However, the regulatory mechanism involved is unknown. Here, we identify the Rap1 effector, RAPL, as an essential regulator in this activation. RAPL was enriched in mouse lymphoid tissues and associated with Rap1 after stimulation by the T cell receptor and with chemokine CXCL12. Human RAPL stimulated lymphocyte polarization and the patch-like redistribution of lymphocyte-function-associated antigen 1 (LFA-1) to the leading edge… Expand
Regulation of lymphocyte adhesion and migration by the small GTPase Rap1 and its effector molecule, RAPL.
TLDR
This work has identified a novel Rap1-binding molecule, regulator of adhesion and cell polarization enriched in lymphoid tissues (RAPL), which is predominantly expressed in immune cells, and mediatesRap1-triggered integrin activation upon TCR engagement and chemokine stimulation. Expand
Spatiotemporal regulation of the kinase Mst1 by binding protein RAPL is critical for lymphocyte polarity and adhesion
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TLDR
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TLDR
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Ezrin is required for efficient Rap1-induced cell spreading
TLDR
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TLDR
It is shown that the extended form of LFA-1 is internalized and in Rap2 siRNA-treated T lymphocytes the trafficking of this L FA-1 conformation is disrupted resulting in its intracellular accumulation. Expand
Rap1-mediated Lymphocyte Function-associated Antigen-1 Activation by the T Cell Antigen Receptor Is Dependent on Phospholipase C-γ1*
TLDR
It is demonstrated that phospholipase C (PLC)-γ1 plays a critical role in the signaling pathway leading to Rap1 activation triggered by the TCR, and that TCR activation of Rap1 depends on CalDAG-GEFI, which is likely to activate LFA-1. Expand
Rap1 controls lymphocyte adhesion cascade and interstitial migration within lymph nodes in RAPL-dependent and -independent manners.
TLDR
Rap1 is indispensably required for the chemokine-triggered initial arrest step of rolling lymphocytes through LFA-1, whereas RAPL is not involved in rapid arrest, and several critical steps of Rap1 are revealed, which are R APL-dependent and -independent, in lymphocyte trafficking. Expand
The Rap1-RIAM-talin axis of integrin activation and blood cell function.
TLDR
Recent progress in understanding the mechanisms of integrin activation with a focus on the functions of blood cells is reviewed, including how talin binding to the integrin β cytoplasmic domain, in conjunction with the plasma membrane, induces long-range allosteric rearrangements that lead to integrinactivation. Expand
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