Ciliary neurotrophic factor stimulates the phosphorylation of two forms of STAT3 in chick ciliary ganglion neurons.
Ciliary neurotrophic factor stimulates the phosphorylation of two forms of STAT3 in chick ciliary ganglion neurons.
复制标题
睫状神经营养因子刺激鸡睫状神经节神经元中两种形式的 STAT3 的磷酸化。
DOI：
10.1074/jbc.272.32.19752
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Halvorsen,SW
中科院分区：
文献类型：
--
作者：
Wishingrad,MA;Koshlukova,S;Halvorsen,SW
睫状神经营养因子（CNTF）是一种神经生成细胞因子，它对培养的鸡睫状神经节神经元具有神经营养活性。CNTF对这些神经元发挥作用的分子机制尚不清楚。我们以前已经确定了睫状神经节神经元上的CNTF功能受体，并证明了CNTF特异性酪氨酸磷酸化的约90 kDa的蛋白质。在这里，我们表明，CNTF诱导快速酪氨酸磷酸化和核积累的这种蛋白质，并确定它作为一种鸟类形式的转录因子，STAT 3。通过其与两种不同的抗STAT 3抗体的识别以及与针对STAT 1、-2、-4、-5或-6的抗体的结合的缺乏来确认鉴定。磷酸化稳定长达2小时，但需要CNTF的持续存在。CNTF还诱导培养的鸡背根神经节和视网膜神经元中类似蛋白的酪氨酸磷酸化。此外，我们确定了第二个，100 kDa的STAT 3形式出现在响应CNTF。与以前的报道不同，利用检测到由H7敏感蛋白磷酸化引起的STAT 3的较慢迁移形式的哺乳动物细胞系，H7没有阻止睫状神经元中100-kDa形式的出现。因此，100 kDa的鸟类蛋白可能代表了CNTF诱导型STAT 3的一种新形式。
Ciliary neurotrophic factor (CNTF) is a neuropoietic cytokine that was identified, purified, and cloned based on its neurotrophic activity on cultured chick ciliary ganglion neurons. The molecular mechanisms by which CNTF elicits its effects on these neurons are unknown. We have previously identified functional receptors for CNTF on ciliary ganglion neurons and demonstrated the CNTF-specific tyrosine phosphorylation of an approximately 90-kDa protein. Here we show that CNTF induced the rapid tyrosine phosphorylation and nuclear accumulation of this protein and identify it as an avian form of the transcription factor, STAT3. Identification was confirmed by its recognition with two distinct anti-STAT3 antibodies and the lack of binding to antibodies against STAT1, -2, -4, -5, or -6. The phosphorylation was stable for up to 2 h but required the continued presence of CNTF. CNTF also induced the tyrosine phosphorylation of a similar protein in cultured chick dorsal root ganglion and retinal neurons. In addition, we identify a second, 100-kDa form of STAT3 that appears in response to CNTF. Unlike previous reports, utilizing mammalian cell lines that detected a slower migrating form of STAT3 resulting from H7-sensitive protein phosphorylation, H7 did not prevent the appearance of the 100-kDa form in ciliary neurons. Thus, the 100-kDa avian protein may represent a novel form of CNTF-inducible STAT3.