RUI: Heavy Metal Detoxification in Crustaceans

本研究将探讨甲壳类动物参与重金属解毒的膜、细胞、组织和器官。本研究的总体目标是揭示美洲龙虾（Homarus americanus）的胃肠道、血液和排泄系统是如何分离并最终消除饮食中可能有毒的环境重金属的。在本项目中，生理和分子生物学技术将用于表征重金属如铜、锌和镉进入和离开胃肠道上皮细胞及其细胞器的机制。此外，这些研究将扩展到龙虾血细胞和触角腺（肾脏）对金属的吸收和排出过程，因为这两个部位参与金属在动物体内的运输，并最终排泄到环境中，因此是这些潜在有毒物质的稳态调节中不可或缺的一部分。拟议的分子研究将涉及使用克隆龙虾特异性cdna来获得重金属膜转运蛋白的全长核苷酸序列。这些核苷酸序列将与已发表的其他生物的类似序列进行比较，以确定物种之间的相似性程度。针对推断出的氨基酸序列的抗体将被合成并用于定位研究，以确定甲壳类动物器官系统解毒机制的组织和细胞分布及其在有机体金属稳态中的潜在作用。这些研究可能对所有生物细胞中的重金属稳态具有广泛的意义，因为金属的毒性是普遍存在的现象。该研究将在刚刚启动其第一个生物学研究生课程的本科研究机构进行，并将部分用于支持本科生和理学硕士研究生的研究活动。学生活动的研究成果将在科学会议上发表，并在适当的期刊上发表。

This study will investigate the membranes, cells, tissues, and organs of crustaceans involved in heavy metal detoxification. The overall objectives of this research will be to disclose how the gastrointestinal tract, blood, and excretory system of the American lobster, Homarus americanus, isolates and eventually eliminates potentially toxic environmental heavy metals obtained in the diet. In this project, physiological and molecular biological techniques will be used to characterize the mechanisms by which heavy metals such as copper, zinc, and cadmium enter and exit gastrointestinal epithelial cells and their organelles. In addition, these studies will extend to uptake and efflux processes for metals that occur in lobster hemocytes and antennal glands (kidneys) since these other two sites are involved in the transport of metals throughout the animal and their eventual excretion to the environment and are therefore integral in the homeostatic regulation of these potentially toxic substances. Proposed molecular studies will involve the use of cloning of lobster-specific cDNAs to obtain full-length nucleotide sequences of heavy metal membrane transporter proteins. These nucleotide sequences will be compared to published analogous sequences from other organisms to determine the extent of similarity between species. Antibodies to deduced amino acid sequences will be synthesized and used in localization studies to determine the tissue and cellular distribution of detoxification mechanisms in crustacean organ systems and their potential roles in organismic metal homeostasis. These studies could have broad implications for heavy metal homeostasis in cells of all organisms since toxic properties of metals are ubiquitous phenomena. The research that will be conducted at an undergraduate research institution that has just initiated its first graduate program in Biology and will be partially used to support research activities of both undergraduate students and Master of Science graduate students. Research results from student activities will be presented at scientific conferences and published in appropriate journals.