Caveolin-1 regulates store-operated Ca2+ influx by binding of its scaffolding domain to transient receptor potential channel-1 in endothelial cells
Caveolin-1 regulates store-operated Ca2+ influx by binding of its scaffolding domain to transient receptor potential channel-1 in endothelial cells
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DOI：
10.1124/mol.105.021741
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发表时间：
2006-10-01
影响因子：
3.6
通讯作者：
Tiruppathi, Chinnaswamy
中科院分区：
文献类型：
--
作者：
Kwiatek, Angela M.;Minshall, Richard D.;Tiruppathi, Chinnaswamy
Caveolin-1与内皮细胞中的储存操纵阳离子通道（SOC）相关。我们研究了小窝蛋白-1支架结构域（CSD）在调节SOC中的作用[即，瞬时受体电位通道-1（TRPC 1）]。我们使用了细胞渗透的触角足（AP）共轭CSD肽，竞争与小窝蛋白-1蛋白结合伙伴，以评估小窝蛋白-1与TRPC 1的相互作用及其对凝血酶诱导的Ca 2+内流的后果。我们观察到，AP-CSD肽显着减少凝血酶诱导的Ca 2+内流通过SOC在HPAEC中，与对照肽。AP-CSD还抑制了毒胡萝卜素诱导的Ca ~（2+）内流。链霉亲和素-珠下拉测定表明生物素标记的AP-CSD肽与TRPC 1的强结合。免疫沉淀研究表明内源性TRPC 1和异位表达的血凝素标记的CSD之间的相互作用。对推导的TRPC 1氨基酸序列的分析揭示了在TRPC 1 C末端存在CSD结合共有序列。我们还观察到，含有CSD结合序列的AP-TRPC 1肽显着减少凝血酶诱导的Ca 2+内流。我们鉴定了生物素标记的AP-TRPC 1 C末端肽与小窝蛋白-1之间的相互作用。因此，这些结果证明了小窝蛋白-1支架结构域与TRPC 1的相互作用在通过SOC调节Ca 2+内流中的关键作用。
Caveolin-1 associates with store-operated cation channels (SOC) in endothelial cells. We examined the role of the caveolin-1 scaffolding domain (CSD) in regulating the SOC [i.e., transient receptor potential channel-1 (TRPC1)] in human pulmonary artery endothelial cells (HPAECs). We used the cell-permeant antennapedia (AP)-conjugated CSD peptide, which competes for protein binding partners with caveolin-1, to assess the interactions of caveolin-1 with TRPC1 and its consequences on thrombin-induced Ca2+ influx. We observed that AP-CSD peptide markedly reduced thrombin-induced Ca2+ influx via SOC in HPAECs in contrast to control peptide. AP-CSD also suppressed thapsigargin-induced Ca2+ influx. Streptavidin-bead pull-down assay indicated strong binding of biotin-labeled AP-CSD peptide to TRPC1. Immunoprecipitation studies demonstrated an interaction between endogenous TRPC1 and ectopically expressed hemagglutinin-tagged CSD. Analysis of the deduced TRPC1 amino acid sequence revealed the presence of CSD binding consensus sequence in the TRPC1 C terminus. We also observed that an AP-TRPC1 peptide containing the CSD binding sequence markedly reduced the thrombin-induced Ca2+ influx. We identified the interaction between biotin-labeled AP-TRPC1 C terminus peptide and caveolin-1. Thus, these results demonstrate a crucial role of caveolin-1 scaffolding domain interaction with TRPC1 in regulating Ca2+ influx via SOC.