Control of transport by epithelia

上皮细胞对运输的控制

• 批准号: RGPIN-2017-05196
• 负责人: Marshall, William
• 金额: $ 2.04万
• 依托单位: St. Francis Xavier University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711242
• 关键词: Control; transport; epithelia

We study mechanisms that animals use to regulate ion and water transport across epithelia. The main model system we use is a hardy teleost fish that frequents estuaries of N. America and is robust to environmental extremes (salinity, temperature, low oxygen, pollution), the mummichog (Fundulus heteroclitus), an important physiological and genomic model species and important as a bioindicator species. The models of the gill osmoregulatory function we use are flat epithelia rich in salt transporting ionocytes, the opercular epithelium in adults and the yolk sac epithelium of embryos. The research focuses on revealing regulatory proteins (kinases and phosphatases) that modulate the transport proteins directly or via kinase cascades. Aim 1. We will discover the regulatory components of the transport complexes that control the anion channel Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) and the cotransporters Na,K,2Cl cotransporter (NKCC1) and NaCl cotransporter (NCC) which include many kinases as well as a calcium-dependent inhibitory pathway. These pathways are activated by osmotic stimuli, neurotransmitters and hormones. The overarching hypothesis is that membrane transport proteins have multiple regulatory components in apparently redundant pathways that regulate ion transport, but in hardy animals such as Fundulus and less hardy tropical fish (Nile tilapia,Oreochromis nilotica), the extreme variation in the environment determines which pathways are best-suited for operation in extreme environments. Aim 2. We will overlay the above with cellular dynamics of this highly regulated transport system using simple salinity changes and immunocytochemistry of transporter proteins to generate cellular succession vs. remodeling of existing ionocytes and their various phenotypic variations in freshwater, seawater and hypersaline conditions. Aim 3. We will use the yolk sac membrane of Fundulus embryos (also salt hardy and rich in ionocytes) to test regulatory pathways using short interfering mRNA (siRNA) injection to block specific kinase/phosphatase genes (confirmed by quantitative PCR) in the yolk sac and see how transport regulation (hypotonic, hypertonic shock, adrenergic agonists) are selectively disrupted to identify the critical components of the regulatory pathways. Importance: Understanding of ion transport and its regulation also informs fisheries and aquaculture and advances comparative physiology. The research will reveal new relationships among regulatory kinases controlling ion transport proteins also associated with disease, particularly CFTR (responsible for cystic fibrosis), NKCC (implicated in pseudohypoaldosteronism) and NCC (involved in Gitelman's syndrome). The work will contribute 19 HQP (BSc and MSc) to Canadian research.

我们研究了动物用于调节上皮细胞离子和水传输的机制。 我们使用的主要模型系统是一种耐铁质的鱼类，它经常使用N. America的河口，并且对环境极端（盐度，温度，低氧，污染），Mummichog（heteroclitus），重要的生理和基因组模型物种，并且作为生物培育物种很重要。我们使用的Gill Osmoregulatoration函数的模型是富含盐的离子细胞，成年人的近端上皮和胚胎囊囊上皮的扁平上皮。 该研究重点是揭示直接或通过激酶级联反应转运蛋白的调节蛋白（激酶和磷酸酶）。 目的1。我们将发现控制阴离子通道囊性纤维化跨膜电导调节剂（CFTR）的调节组件和旋转孢子Na，K，2cl cotransporter（NKCC1）和NaCl cotransporter（NCC）（NCC）（NCC）（NCC），其中包括许多基因酶以及许多基因酶以及钙化量的依赖性依赖性依赖性。这些途径被渗透刺激，神经递质和激素激活。总体假设是，膜转运蛋白在显然冗余的途径中具有多个调节成分，但在调节离子传输的冗余途径中，但是在诸如白细胞和较少强化的热带鱼类（Nile Tilapia，Oreochromis nilotica）等硬天性动物中，环境中的极端变化是最佳环境的极端环境。 AIM 2。我们将使用该高度调节的运输系统的细胞动力学覆盖上述盐度变化和转运蛋白的免疫细胞化学，以产生细胞依次与现有离子细胞的重塑及其在淡水，海水和催化疾病中的各种表型变化。 Aim 3. We will use the yolk sac membrane of Fundulus embryos (also salt hardy and rich in ionocytes) to test regulatory pathways using short interfering mRNA (siRNA) injection to block specific kinase/phosphatase genes (confirmed by quantitative PCR) in the yolk sac and see how transport regulation (hypotonic, hypertonic shock, adrenergic agonists) are selectively disrupted to确定监管途径的关键组成部分。重要性：对离子运输及其法规的理解也为渔业和水产养殖提供了依据，并进步了比较生理学。这项研究将揭示控制离子转运蛋白的调节激酶之间的新关系，也与疾病有关，尤其是CFTR（负责囊性纤维化），NKCC（与假氧化甲醛酸溶血质体）和NCC有关（参与Gitelman综合征）。 这项工作将为加拿大研究贡献19 HQP（BSC和MSC）。