Association of the X-linked lymphoproliferative disease gene product SAP/SH2D1A with 2B4, a natural killer cell-activating molecule, is dependent on phosphoinositide 3-kinase - PubMed (original) (raw)

. 2002 Apr 12;277(15):13331-7.

doi: 10.1074/jbc.M112029200. Epub 2002 Jan 28.

Affiliations

Free article

Association of the X-linked lymphoproliferative disease gene product SAP/SH2D1A with 2B4, a natural killer cell-activating molecule, is dependent on phosphoinositide 3-kinase

Ala Aoukaty et al. J Biol Chem. 2002.

Free article

Abstract

Natural killer (NK) cells express an activating receptor, 2B4, that enhances cellular cytotoxicity. Upon NK cell activation by ligation of 2B4, the intracellular domain of 2B4 associates with the X-linked lymphoproliferative disease (XLP) gene product, signaling lymphocytic activation molecule-associated protein/SH2D1A (SAP/SH2D1A). Defective intracellular association of 2B4 with mutated SAP/SH2D1A is likely to underlie the defects in cytotoxicity observed in NK cells from patients with XLP. We report here a role for phosphoinositide 3-kinase (PI3K) in the recruitment and association of SAP/SH2D1A to 2B4 in human NK cells. The activation of normal NK cells by ligation of 2B4 leads to the phosphorylation of 2B4, recruitment of SAP/SH2D1A, and association of the p85 regulatory subunit of PI3K. The inhibition of PI3K enzymatic activity with either wortmannin or LY294002 prior to 2B4 ligation does not alter the association of 2B4 with the p85 subunit but prevents the recruitment of SAP/SH2D1A to 2B4. In addition, PI3K inhibitors significantly diminish the cytotoxic function of primary NK cells. This observed inhibition of cytotoxicity, present in normal NK cells, was less apparent or absent in NK cells derived from a patient with XLP. These data indicate that the cytotoxicity of activated NK cells is mediated by the association of 2B4 and SAP/SH2D1A, and that this association is dependent upon the activity of PI3K.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources