An integrated, multi-level analysis of thermal effects on intertidal molluscs for understanding species distribution patterns
An integrated, multi-level analysis of thermal effects on intertidal molluscs for understanding species distribution patterns
复制标题
对潮间带软体动物的热效应进行综合、多层次分析，以了解物种分布模式
DOI：
10.1111/brv.12811
复制
发表时间：
2021-10-29
影响因子：
10
通讯作者：
Somero, George N.
中科院分区：
文献类型：
--
作者：
Dong, Yun-wei;Liao, Ming-ling;Somero, George N.
阐明热应激背后的生理机制，并发现物种在表型适应和进化适应这种应激的能力方面有何不同，对于了解物种当前的纬度和垂直分布模式以及预测它们在变暖世界中的未来状态至关重要。这种机制分析需要仔细选择研究系统（物种和温度敏感性状）并设计反映原位条件复杂性的实验室实验。在这里，我们批判性地回顾了潮间带软体动物的广泛研究，这些研究提供了生物组织各个层面（行为、组织、器官水平、细胞、分子和基因组）热效应的机制解释，并展示了温度敏感特征如何控制分布模式和应对热应激的能力。来自不同热栖息地的同源物的比较是识别适应性变异的特别有效的手段。我们利用这些机制分析来说明物种在温度升高所造成的威胁严重程度方面有何不同。与直觉相反的是，我们发现一些最耐热的物种可能最容易受到温度升高的威胁，因为它们的热安全裕度较小且适应较高温度的能力最小。我们讨论了最近的分子生物学和基因组研究，这些研究为理解蛋白质结构、RNA 二级结构、基因组内容和适应温度的基因表达能力的进化变化类型提供了重要基础。在耐热软体动物中发现的与应激相关的基因的复制可能会增强应对高温的能力。我们认为，在潮间带软体动物中发现的解剖、行为、生理和基因组多样性通常在这些生态系统中至关重要且丰富，使该类动物成为非常适合解决潮间带生物当前和未来分布模式的机械决定因素问题的研究系统。
Elucidating the physiological mechanisms that underlie thermal stress and discovering how species differ in capacities for phenotypic acclimatization and evolutionary adaptation to this stress is critical for understanding current latitudinal and vertical distribution patterns of species and for predicting their future state in a warming world. Such mechanistic analyses require careful choice of study systems (species and temperature-sensitive traits) and design of laboratory experiments that reflect the complexities of in situ conditions. Here, we critically review a wide range of studies of intertidal molluscs that provide mechanistic accounts of thermal effects across all levels of biological organization - behavioural, organismal, organ level, cellular, molecular, and genomic - and show how temperature-sensitive traits govern distribution patterns and capacities for coping with thermal stress. Comparisons of congeners from different thermal habitats are especially effective means for identifying adaptive variation. We employ these mechanistic analyses to illustrate how species differ in the severity of threats posed by rising temperature. Counterintuitively, we show that some of the most heat-tolerant species may be most threatened by increases in temperatures because of their small thermal safety margins and minimal abilities to acclimatize to higher temperatures. We discuss recent molecular biological and genomic studies that provide critical foundations for understanding the types of evolutionary changes in protein structure, RNA secondary structure, genome content, and gene expression capacities that underlie adaptation to temperature. Duplication of stress-related genes, as found in heat-tolerant molluscs, may provide enhanced capacity for coping with higher temperatures. We propose that the anatomical, behavioural, physiological, and genomic diversity found among intertidal molluscs, which commonly are of critical importance and high abundance in these ecosystems, makes this group of animals a highly appropriate study system for addressing questions about the mechanistic determinants of current and future distribution patterns of intertidal organisms.