The Role of Bioactive Lipids in Transient Receptor Potential Channels Gating

血压调节依赖于膜蛋白对物理刺激变化的适应能力 (e.g.,血液动力学力）转换成电信号。瞬时受体电位香草酸4（TRPV 4）是一种具有高亲和力的蛋白质， 机械敏感性Ca ~（2+）通道在内皮细胞、平滑肌细胞和血管周围组织中表达 感觉神经元尽管TRPV 4参与了内皮和血管周围神经依赖性 血管舒张，其精确的门控机制仍然难以捉摸。已经提出在机械刺激后激活TRPV 4的三种机制：1）ω（ω）-6花生四烯酸（AA）及其代谢物环氧二十碳三烯酸（E3）的磷脂酶A2（PLA 2）依赖性形成的下游; 2）嘌呤能P2 Y2受体激活的下游，由三磷酸腺苷释放介导;和3）通过膜拉伸直接激活。我们的长期目标是阐明离子通道解码外源性和内源性刺激以调节细胞功能的机制。在这项提案中，总体目标是建立TRPV 4激活的分子基础。核心假设是TRPV 4的激活是 通过脂质重塑由膜的机械性质调节。建议的理由 研究计划是，一旦TRPV 4激活的精确机制被阐明， 确定靶向TRPV 4的策略以控制全身血压。该假设将通过以下方式进行检验： 追求三个具体目的：1）确定w-6和w-3脂肪酸对C. 2）检验w-3脂肪酸衍生物增强血管细胞中TRPV 4活性的假设;和3） 确定膜的机械性质的变化如何调节TRPV 4门控。我们将利用遗传，行为，功能，生物化学和生物物理方法来揭示脂肪酸及其代谢产物对TRPV 4功能的贡献。这项研究计划是创新的，因为它将决定 w-3和w-6脂肪酸及其类二十烷酸衍生物对TRPV 4门控的单独贡献。这项研究意义重大，因为它有望在靶向TRPV 4方面具有广泛的翻译重要性。 来调节血管和神经功能。

Blood pressure regulation relies on the ability of membrane proteins to transduce variations in physical stimuli (e.g., hemodynamic forces) into electrical signals. The transient receptor potential vanilloid 4 (TRPV4) is a pu- tative mechanosensitive Ca2+ channel expressed in endothelial and smooth muscle cells and in perivascular sensory neurons. Although TRPV4 has been implicated in endothelium- and perivascular nerve-dependent vasorelaxation, its precise gating mechanism remains elusive. Three mechanisms have been proposed to activate TRPV4 after mechanical stimulation: 1) downstream of the phospholipase A2 (PLA2)-dependent formation of omega (w)-6 arachidonic acid (AA) and its metabolites, epoxyeicosatrienoic acids (EETs); 2) downstream of purinergic P2Y2 receptor activation, mediated by adenosine triphosphate release; and 3) direct activation by membrane stretch. Our long-term goal is to delineate the mechanisms by which ion channels decode exogenous and endogenous stimuli to regulate cellular function. In this proposal, the overall objective is to establish the molecular basis underlying TRPV4 activation. The central hypothesis is that TRPV4 activation is regulated by the mechanical properties of the membrane via lipid remodeling. The rationale for the proposed research plan is that once the precise mechanism of TRPV4 activation has been elucidated, it will be possible to define strategies that target TRPV4 to control systemic blood pressure. The hypothesis will be tested by pursuing three Specific Aims: 1) Determine the effect of w-6 and w-3 fatty acids on TRPV4 activity in C. elegans; 2) Test the hypothesis that w-3 fatty acid derivatives enhance TRPV4 activity in vascular cells; and 3) Determine how changes in the mechanical properties of the membrane regulates TRPV4 gating. We will leverage genetic, behavioral, functional, biochemical, and biophysical approaches to uncover the contribution of fatty acids and their metabolites to TRPV4 function. The research plan is innovative because it will determine the individual contribution of w-3 and w-6 fatty acids and their eicosanoid derivatives to TRPV4 gating. The proposed research is significant because it is expected to have broad translational importance in targeting TRPV4 to regulate vascular and neuronal function.