Phenotypic Plasticity, Costs of Phenotypes, and Costs of Plasticity Toward an Integrative View
Phenotypic Plasticity, Costs of Phenotypes, and Costs of Plasticity Toward an Integrative View
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DOI：
10.1196/annals.1438.008
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发表时间：
2008-01-01
期刊：
影响因子：
--
通讯作者：
Steiner, Ulrich K.
中科院分区：
文献类型：
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作者：
Callahan, Hilary S.;Maughan, Heather;Steiner, Ulrich K.
为什么有些特征是构成性的，而另一些是诱导性的？成本一词经常出现在处理这一问题的工作中，但可能定义模糊。这篇评论区分了两种概念上不同类型的成本：表型成本和可塑性成本。表型成本是从协变的模式，通常是一个焦点性状和一个单独的性状相关的健身评估。可塑性成本，从表型成本分离，衡量两个环境中，但不同的可塑性和健身的基因型与等效表型的健身比较。与这两种类型的成本的微妙之处说明了一个机构的工作解决捕食者引起的可塑性。这种微妙之处以及两种成本之间的潜在相互作用也得到了解决，通常是在涉及遗传模式生物的研究中。在某些情况下，研究人员已经确定了可塑性的机械基础。在这种情况下，微生物研究尤其具有启发性，并且具有三个额外的优势。首先，关于可塑性机制的信息，如结构和调节基因、感觉蛋白和生化途径，有助于将群体水平的研究与潜在的生理和遗传机制联系起来。其次，微生物研究涉及许多代，大种群和复制。最后，关键参数的经验估计（例如，突变率）是易处理的。总之，这些允许严格的调查基因的相互作用，漂移，突变和选择，所有潜在的因素影响的维持或诱导性状的损失沿着表型和可塑性成本。来自微生物工作的信息可以指导未来的努力，以了解不同生物体中塑料性状的进化。
Why are some traits constitutive and others inducible? The term costs often appears in work addressing this issue but may be ambiguously defined. This review distinguishes two conceptually distinct types of costs: phenotypic costs and plasticity costs. Phenotypic costs are assessed from patterns of covariation, typically between a focal trait and a separate trait relevant to fitness. Plasticity costs, separable from phenotypic costs, are gauged by comparing the fitness of genotypes with equivalent phenotypes within two environments but differing in plasticity and fitness. Subtleties associated with both types of costs are illustrated by a body of work addressing predator-induced plasticity. Such subtleties, and potential interplay between the two types of costs, have also been addressed, often in studies involving genetic model organisms. In some instances, investigators have pinpointed the mechanistic basis of plasticity. In this vein, microbial work is especially illuminating and has three additional strengths. First, information about the machinery underlying plasticity-such as structural and regulatory genes, sensory proteins, and biochemical pathways-helps link population-level studies with underlying physiological and genetic mechanisms. Second, microbial studies involve many generations, large populations, and replication. Finally, empirical estimation of key parameters (e.g., mutation rates) is tractable. Together, these allow for rigorous investigation of gene interactions, drift, mutation, and selection-all potential factors influencing the maintenance or loss of inducible traits along with phenotypic and plasticity costs. Messages emerging from microbial work can guide future efforts to understand the evolution of plastic traits in diverse organisms.