Research Planning Grant: Lipid Restructuring in Gill Plasma Membranes: An Investigation of Domain-Specific Responses in Euryhaline Teleosts During Salinity Adaptation

许多河口或潮间带鱼类暴露于波动的盐度，而其他鱼类之间的淡水和海洋网站迁移。 这些动物的溶质平衡可能会发生剧烈变化，但它们通过一系列行为、系统水平、细胞和生化适应来抵消水和离子的被动通量，从而将体液浓度维持在相对较窄的范围内。 由于鳃负责大多数气体交换，消除含氮废物，酸碱平衡，以及几乎所有硬骨鱼类的新陈代谢调节，因此它代表了动物与环境之间的关键界面。 相对较少的注意力集中在化学和物理性质的鳃，使这个接口的质膜。 克罗克特博士将检验这一假设，即鳃顶端质膜结构域的脂质组成在淡水和海水适应的鱼类中有显着差异。 为了（1）确保膜的完整性和渗透性，（2）减少表面电荷密度的变化，（3）维持有序和相态等膜物理性质，（4）提供允许膜相关蛋白质充分活性的微环境，可能发生脂质变化。 在18个月的规划期内，克罗克特博士将描述鱼类在适应不同环境盐度期间鳃质膜结构域中脂质成分的重组特征。 这项工作将确定哪些脂类（磷脂、糖脂、胆固醇）参与盐度适应。 结果将（1）建立一个协议，同时准备鳃顶端和基底外侧域和（2）提供第一次看到鳃质膜重组在鱼类盐度适应。

Many estuarine or intertidal fishes are exposed to fluctuating salinities, while other fishes migrate between freshwater and marine sites. These animals' solute balance might change drastically, but they maintain concentrations of their body fluids in a relatively narrow range with a suite of behavioral, systems-level, cellular, and biochemical adaptations to offset the passive fluxes of water and ions. Because the gill is responsible for the majority of gas exchange, elimination of nitrogenous waste, acid-base balance, and osmoregulation in virtually all teleost fishes, it represents a key interface between animal and environment. Relatively little attention has focused on chemical and physical properties of the plasma membranes of the gill that make up this interface. Dr. Crockett will test the hypothesis that lipid compositions of apical plasma-membrane domains from the gill are significantly different in freshwater- and seawater-acclimated fishes. Lipid changes are likely to occur in order to (1) ensure membrane integrity and permeability properties, (2) reduce changes in surface-charge density, (3) maintain such membrane physical properties as order and phase state, and (4) provide a micro-environment that permits sufficient activity of membrane-associated proteins. During the 18-month planning period, Dr. Crockett will characterize restructuring of the lipid components in gill plasma-membrane domains from fishes during adaptation to varying environmental salinities. This work will establish which lipid class(es) (phospholipids, glycolipids, cholesterol) is (are) involved in salinity adaptation. Results will (1) establish a protocol to prepare simultaneously gill apical and basolateral domains and (2) provide the first look at gill plasma-membrane restructuring during salinity adaptation in fishes.