Gleason Lani U, Miller Luke P, Winnikoff Jacob R, Somero George N, Yancey Paul H, Bratz Dylan, Dowd W Wesley
Loyola Marymount University, Department of Biology, 1 LMU Drive, Los Angeles, CA 90045, USA
San Jose State University, Department of Biological Sciences, One Washington Square, San Jose, CA 95192, USA.
J Exp Biol. 2017 Nov 15;220(Pt 22):4292-4304. doi: 10.1242/jeb.168450.
The ability of animals to cope with environmental stress depends - in part - on past experience, yet knowledge of the factors influencing an individual's physiology in nature remains underdeveloped. We used an individual monitoring system to record body temperature and valve gaping behavior of rocky intertidal zone mussels (). Thirty individuals were selected from two mussel beds (wave-exposed and wave-protected) that differ in thermal regime. Instrumented mussels were deployed at two intertidal heights (near the lower and upper edges of the mussel zone) and in a continuously submerged tidepool. Following a 23-day monitoring period, measures of oxidative damage to DNA and lipids, antioxidant capacities (catalase activity and peroxyl radical scavenging) and tissue contents of organic osmolytes were obtained from gill tissue of each individual. Univariate and multivariate analyses indicated that inter-individual variation in cumulative thermal stress is a predominant driver of physiological variation. Thermal history over the outplant period was positively correlated with oxidative DNA damage. Thermal history was also positively correlated with tissue contents of taurine, a thermoprotectant osmolyte, and with activity of the antioxidant enzyme catalase. Origin site differences, possibly indicative of developmental plasticity, were only significant for catalase activity. Gaping behavior was positively correlated with tissue contents of two osmolytes. Overall, these results are some of the first to clearly demonstrate relationships between inter-individual variation in recent experience in the field and inter-individual physiological variation, in this case within mussel beds. Such micro-scale, environmentally mediated physiological differences should be considered in attempts to forecast biological responses to a changing environment.
动物应对环境压力的能力部分取决于过去的经历，然而，对于影响个体在自然环境中生理状态的因素，我们的了解仍很有限。我们使用个体监测系统记录了岩石潮间带贻贝的体温和瓣膜张开行为。从两个热状况不同的贻贝床（受浪冲击和不受浪冲击）中选取了30个个体。将装有仪器的贻贝放置在两个潮间带高度（贻贝区的上下边缘附近）以及一个持续淹没的潮池中。在为期23天的监测期之后，从每个个体的鳃组织中获取了DNA和脂质氧化损伤的测量值、抗氧化能力（过氧化氢酶活性和过氧自由基清除能力）以及有机渗透溶质的组织含量。单变量和多变量分析表明，累积热应激的个体间差异是生理变化的主要驱动因素。移植期的热历史与氧化性DNA损伤呈正相关。热历史还与热保护渗透溶质牛磺酸的组织含量以及抗氧化酶过氧化氢酶的活性呈正相关。起源地差异可能表明发育可塑性，仅在过氧化氢酶活性方面具有显著性。瓣膜张开行为与两种渗透溶质的组织含量呈正相关。总体而言，这些结果首次清晰地证明了在野外近期经历的个体间差异与个体间生理差异之间的关系，在本研究中是贻贝床内的差异。在试图预测生物对不断变化的环境的反应时，应考虑这种微观尺度、由环境介导的生理差异。
