The phosphorylation of endogenous Nedd4-2 In Na(+)-absorbing human airway epithelial cells.
The phosphorylation of endogenous Nedd4-2 In Na(+)-absorbing human airway epithelial cells.
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DOI：
10.1016/j.ejphar.2014.03.005
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发表时间：
2014-06-05
影响因子：
5
通讯作者：
Wilson, Stuart M.
中科院分区：
文献类型：
--
作者：
Ismail, Noor A. S.;Baines, Deborah L.;Wilson, Stuart M.
关键词：
神经前体细胞表达的发育下调蛋白4-2（Nedd 4 -2）介导上皮Na+通道亚基（α-、β-和γ-ENaC）的内化/降解。血清/糖皮质激素诱导激酶1（SGK 1）和蛋白激酶A（PKA）似乎都通过磷酸化Nedd 4 -2-Ser 221、-Ser 327和-Thr 246来抑制该过程。这种Nedd 4 -2失活过程被认为是Na+吸收的激素控制的核心。因此，本研究的H441人气道上皮细胞探索SGK 1和/或PKA对内源性Nedd 4 -2的磷酸化/丰度的影响; ENaC亚基的表面表达，和产电Na+转运。通过蛋白质印迹分析监测对Nedd 4 -2磷酸化/丰度和ENaC表面表达的影响，同时通过电测量定量Na+吸收。急性（20分钟）激活PKA在糖皮质激素剥夺（24小时）的细胞增加的丰度Ser 221-磷酸化，Ser 327-磷酸化和总Nedd 4 -2没有改变的Thr 246-磷酸化Nedd 4 - 2的丰度。在这些条件下激活PKA不会引起α-、β-和γ-ENaC表面丰度的协同增加，并且对生电Na+吸收只有非常小的影响。另一方面，在糖皮质激素处理（0.2 µM地塞米松，24 h）的细胞中激活PKA（20 min），增加了Ser 221-、Ser 327-和Thr 246-磷酸化和总Nedd 4 -2的丰度;增加了α-、β-和γ-ENaC的表面丰度，并引起了Na+转运的明显刺激。因此，慢性糖皮质激素刺激似乎通过促进PKA对Nedd 4 -2和ENaC亚基的作用，允许cAMP依赖性控制Na+吸收。
Neural precursor cell expressed, developmentally down-regulated protein 4-2 (Nedd4-2) mediates the internalisation / degradation of epithelial Na+ channel subunits (α-, β- and γ-ENaC). Serum / glucocorticoid inducible kinase 1 (SGK1) and protein kinase A (PKA) both appear to inhibit this process by phosphorylating Nedd4-2-Ser221, -Ser327 and -Thr246. This Nedd4-2 inactivation process is thought to be central to the hormonal control of Na+ absorption. The present study of H441 human airway epithelial cells therefore explores the effects of SGK1 and / or PKA upon the phosphorylation / abundance of endogenous Nedd4-2; the surface expression of ENaC subunits, and electrogenic Na+ transport. Effects on Nedd4-2 phosphorylation/abundance and the surface expression of ENaC were monitored by western analysis, whilst Na+ absorption was quantified electrometrically. Acutely (20 min) activating PKA in glucocorticoid-deprived (24 h) cells increased the abundance of Ser221-phosphorylated, Ser327-phosphorylated and total Nedd4-2 without altering the abundance of Thr246-phosphorylated Nedd4-2. Activating PKA under these conditions did not cause a co-ordinated increase in the surface abundance of α-, β- and γ-ENaC and had only a very small effect upon electrogenic Na+ absorption. Activating PKA (20 min) in glucocorticoid-treated (0.2 µM dexamethasone, 24 h) cells, on the other hand, increased the abundance of Ser221-, Ser327- and Thr246-phosphorylated and total Nedd4-2; increased the surface abundance of α-, β- and γ-ENaC and evoked a clear stimulation of Na+ transport. Chronic glucocorticoid stimulation therefore appears to allow cAMP-dependent control of Na+ absorption by facilitating the effects of PKA upon the Nedd4-2 and ENaC subunits.
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影响因子：
16.6
作者：
Boase, Natasha A.;Rychkov, Grigori Y.;Townley, Scott L.;Dinudom, Anuwat;Candi, Eleanora;Voss, Anne K.;Tsoutsman, Tatiana;Semsarian, Chris;Melino, Gerry;Koentgen, Frank;Cook, David I.;Kumar, Sharad
通讯作者：
Kumar, Sharad
DOI：
10.1165/2009-0335oc
发表时间：
2011-01-01
影响因子：
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作者：
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通讯作者：
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影响因子：
4.1
作者：
Murray, JT;Campbell, DG;Cohen, P
通讯作者：
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影响因子：
3.5
作者：
Murray, JT;Cummings, LA;Cohen, P
通讯作者：
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DOI：
10.1152/ajplung.00412.2002
发表时间：
2003-08-01
影响因子：
4.9
作者：
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通讯作者：
Matalon, S