Physiological Determinants of Vertical Zonation in Congeneric Marine Invertebrates: Comparative Analysis of Species Replacement Along the Subtidal to Intertidal Gradient

同属海洋无脊椎动物垂直分带的生理决定因素：沿潮下至潮间梯度物种替换的比较分析

• 批准号: 0133184
• 负责人: George Somero
• 金额: $ 55万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0133184&HistoricalAwards=false
• 关键词: Physiological; Determinants; Vertical; Zonation; Congeneric

A question of great interest to ecologists and evolutionary biologists is, "Why do species occur in certain habitats and not in others?" One basis for governing the distributions of species is their tolerance of physical factors in the environment, notably ambient temperature. This fact is illustrated especially clearly in rocky intertidal habitats: In the gradient from the subtidal region to the intertidal zone, thermal conditions vary sharply, as does the set of species found along this transect. It is common for one species of a genus to be replaced by a closely related species of the same genus (a congener). The studies supported by this proposal examine the physiological, biochemical and molecular differences among congeners from different vertical sites in an effort to identify adaptive differences that help to explain variation in distribution patterns. The systems to be studied include: (i) the heat-shock response, a rescue system for repairing heat-damaged proteins; (ii) heart function, which is markedly sensitive to temperature; (iii) membrane integrity, which is essential for many physiological processes, and (iv) nerve function, which may be of importance in setting thermal tolerance limits. Techniques to be used include a wide variety of molecular methods (sequencing of genes and analysis of gene expression patterns), biochemical approaches (measurement of levels of heat-damaged proteins) and physiological analyses (rates of heart function and generation of nerve signals). Study species include snails of the genus Tegula and porcelain crabs (genus Petrolisthes). Both sets of congeners occur over wide vertical and latitudinal ranges and thus are excellent study systems for elucidating mechanisms of adaptation to temperature. The study of congeners adapted to different temperatures allows a particularly clear picture to be developed of the role of adaptive change in establishing environmental optima and tolerance limits. By identifying the underlying mechanisms that establish thermal optima and limits, the effects of predicted global warming could be understood in a more definitive manner.

生态学家和进化生物学家非常感兴趣的一个问题是，“为什么物种只出现在某些栖息地，而不在其他栖息地？“控制物种分布的一个基础是它们对环境中物理因素的耐受性，特别是环境温度。这一事实在岩石潮间带栖息地中表现得尤为明显：从潮下带到潮间带的梯度中，温度条件变化剧烈，沿着这条横断面发现的物种也是如此。 一个属的一个物种被同一属的一个密切相关的物种（同源物）所取代是很常见的。 本提案所支持的研究审查了来自不同垂直地点的同系物之间的生理、生物化学和分子差异，以确定有助于解释分布模式变化的适应性差异。 待研究的系统包括：（i）热休克反应，修复热损伤蛋白质的救援系统;（ii）心脏功能，对温度非常敏感;（iii）膜完整性，这对许多生理过程至关重要;（iv）神经功能，这可能对设定热耐受极限很重要。将使用的技术包括各种各样的分子方法（基因测序和基因表达模式分析）、生物化学方法（测量热损伤蛋白质的水平）和生理分析（心脏功能的速率和神经信号的产生）。研究物种包括Tegula属的蜗牛和瓷蟹（岩蟹属）。这两套同源物发生在广泛的垂直和纬度范围，因此是很好的研究系统，阐明适应温度的机制。对适应不同温度的同源物的研究可以特别清楚地了解适应性变化在确定最佳环境和容许限度方面的作用。 通过确定建立热最佳和极限的基本机制，可以更明确地理解预测的全球变暖的影响。