Adaptation of Photoreceptor Physiology to Life History Stage in Ontogenetically Migrating Deep-Sea Crustaceans

光感受器生理学对个体发生迁移深海甲壳动物生命史阶段的适应

• 批准号: 0343871
• 负责人: Tamara Frank
• 金额: $ 27.01万
• 依托单位: Harbor Branch Oceanographic Institution, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0343871&HistoricalAwards=false
• 关键词: Adaptation; Photoreceptor; Physiology; Life; History

A number of marine species have a difficult problem to deal with, in that they live in vastly different light environments during the course of their lifetimes. These species are ontogenetic migrators, in that the young juveniles stages live in relatively brightly lit shallow waters, while the older adult stages may live 1000 m deeper, where there is very little light. Virtually nothing is known about how these two life history stages adapt to these dramatically different light environments. Is it a matter of possessing an eye that works in both bright and dim light, but isn't really the best design for optimal vision under either condition? Or are there mechanisms in place that allow for the conversion of an eye designed to function well in bright light to one that functions well in very dim light, over a timeframe of less than a year? This proposal seeks to examine whether deep-living adults are substantially more sensitive to light than shallow-living juveniles, as well as the mechanisms involved in producing these sensitivity differences, if they exist, in a variety of crustacean species. This will be done by using combination of physiological, molecular and histological techniques to examine various characteristics of their eyes, namely their sensitivity to light, their structure and optics, and their visual pigments. Many of these crustacean species are major components of the oceanic food webs that support the major commercial fisheries, and understanding whether and how they adapt to different light environments is critical to modeling what effect a change in their light environment (such as a change in water clarity due to pollution) may have on their distribution patterns. In addition, the enormous dorsal eye of hydrothermal vent shrimp will be examined. To date, the dorsal eyes of all the hydrothermal vent shrimp that have been collected show signs of significant light damage. This has given rise to the concern that these eyes may be remarkably sensitive structures that are being destroyed by light, and led to the suggestion that a majority of the vent shrimp at heavily studied vent sites are being permanently blinded by repeated exposure to ROV and submersible. Unfortunately, all the shrimp that have been examined have been collected under extremely bright artificial lights, and it has been impossible to determine whether all the light damage occurred during the collection, or was due to some past exposure to artificial lights as well. With newly designed collecting techniques that will allow collection of these species without exposure to light, this proposal seeks to study the sensitivity of a dorsal eye that has never been exposed to light, as well as the cumulative effects of repeated exposure to floodlight illumination in the laboratory. This research will provide data to address the issue of whether sanctuary type no-visit zones need to be designated in order to study the ecological impact of blinding a majority of the mobile organisms in an ecosystem.

许多海洋物种都有一个很难处理的问题，因为它们一生中生活在截然不同的光环境中。这些物种是个体发生的迁徙者，因为年轻的幼鱼阶段生活在相对明亮的浅水中，而年长的成年阶段可能生活在1000米深的地方，那里的光线很少。实际上，我们对这两个生命阶段如何适应这些截然不同的光环境一无所知。是不是拥有一只在明亮和昏暗的光线下都能工作的眼睛，但在任何一种情况下都不是最佳的设计？或者是否存在某种机制，能在不到一年的时间内，让一只原本能在强光下正常工作的眼睛，在非常昏暗的光线下正常工作？该提案旨在研究生活在深海的成虫是否比生活在浅海的幼虫对光线更敏感，以及在各种甲壳类物种中产生这些敏感性差异的机制，如果它们存在的话。这将通过结合使用生理、分子和组织学技术来检查他们眼睛的各种特征，即他们对光的敏感性，他们的结构和光学，以及他们的视觉色素。许多甲壳类动物是支持主要商业渔业的海洋食物网的主要组成部分，了解它们是否以及如何适应不同的光环境对于模拟它们的光环境变化（如由于污染导致的水清晰度变化）可能对其分布模式产生的影响至关重要。此外，还将研究热液喷口虾巨大的背眼。迄今为止，所有收集到的热液喷口虾的背部眼睛都有明显的光损伤迹象。这引起了人们的担忧，即这些眼睛可能是非常敏感的结构，正在被光线破坏，并导致人们认为，在经过大量研究的喷口地点，大多数喷口虾由于反复暴露在ROV和潜水器中而永久失明。不幸的是，所有被检查的虾都是在非常明亮的人工灯光下收集的，因此无法确定所有的光损伤是在收集过程中发生的，还是由于过去暴露在人工灯光下造成的。通过新设计的收集技术，可以在不暴露于光的情况下收集这些物种，本提案旨在研究从未暴露于光的背眼的敏感性，以及在实验室中反复暴露于泛光灯照明的累积效应。这项研究将提供数据，以解决是否需要指定保护区类型的禁入区，以便研究生态系统中大多数移动生物的盲化对生态的影响。