The tyrosine kinase p56lck mediates activation of swelling-induced chloride channels in lymphocytes.
The tyrosine kinase p56lck mediates activation of swelling-induced chloride channels in lymphocytes.
复制标题
酪氨酸激酶p56LCK介导淋巴细胞中溶胀诱导的氯化物通道的激活。
DOI:
10.1083/jcb.141.1.281
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发表时间:
1998-04-06
期刊:
影响因子:
--
通讯作者:
Lang F
中科院分区:
文献类型:
--
作者:
Lepple-Wienhues A;Szabò I;Laun T;Kaba NK;Gulbins E;Lang F
Osmotic cell swelling activates Cl− channels to achieve anion efflux. In this study, we find that both the tyrosine kinase inhibitor herbimycin A and genetic knockout of p56lck, a src-like tyrosine kinase, block regulatory volume decrease (RVD) in a human T cell line. Activation of a swelling-activated chloride current (ICl−swell) by osmotic swelling in whole-cell patch-clamp experiments is blocked by herbimycin A and lavendustin. Osmotic activation of ICl−swell is defective in p56lck-deficient cells. Retransfection of p56lck restores osmotic current activation. Furthermore, tyrosine kinase activity is sufficient for activation of ICl−swell. Addition of purified p56lck to excised patches activates an outwardly rectifying chloride channel with 31 pS unitary conductance. Purified p56lck washed into the cytoplasm activates ICl−swell in native and p56lck-deficient cells even when hypotonic intracellular solutions lead to cell shrinkage. When whole-cell currents are activated either by swelling or by p56lck, slow single-channel gating events can be observed revealing a unitary conductance of 25–28 pS. In accordance with our patch-clamp data, osmotic swelling increases activity of immunoprecipitated p56lck. We conclude that osmotic swelling activates ICl−swell in lymphocytes via the tyrosine kinase p56lck.