Department of Biological Sciences, University of North Carolina Charlotte, Charlotte, NC, 28223, USA.
Cell Stress Chaperones. 2018 Sep;23(5):933-941. doi: 10.1007/s12192-018-0900-7. Epub 2018 Apr 25.
Marine organisms experience abiotic stressors such as fluctuations in temperature, UV radiation, salinity, and oxygen concentration. Heat shock proteins (HSPs) assist in the response of cells to these stressors by refolding and maintaining the activity of damaged proteins. The well-conserved Hsp70 chaperone family is essential for cell viability as well as the response to stress. Organisms possess a variety of Hsp70 isoforms that differ slightly in amino acid sequence, yet very little is known about their functional relevance. In this study, we undertook analysis of three principal Hsp70 isoforms NvHsp70A, B, and D from the starlet sea anemone Nematostella vectensis. The functionality of Hsp70 isoforms in the starlet sea anemone was assessed through transcriptional analysis and by heterologous expression in budding yeast Saccharomyces cerevisiae. Interestingly, these isoforms were found to not only differ in expression under stress but also appear to have functional differences in their ability to mediate the cellular stress program. These results contribute to an understanding of Hsp70 isoform specificity, their shared and unique roles in response to acute and chronic environmental stress, and the potential basis of local adaptation in populations of N. vectensis.
海洋生物体会经历非生物胁迫因素，如温度波动、紫外线辐射、盐度和氧气浓度等。热休克蛋白 (HSPs) 通过重折叠和维持受损蛋白质的活性来帮助细胞应对这些胁迫因素。高度保守的 Hsp70 伴侣家族对于细胞活力以及对压力的反应都是必不可少的。生物体内拥有多种 Hsp70 同工型，它们在氨基酸序列上略有不同，但对其功能相关性知之甚少。在这项研究中，我们对来自星状海葵 Nematostella vectensis 的三种主要 Hsp70 同工型 NvHsp70A、B 和 D 进行了分析。通过转录分析和在出芽酵母酿酒酵母中的异源表达，评估了 Hsp70 同工型在星状海葵中的功能。有趣的是，这些同工型不仅在应激下的表达存在差异，而且在介导细胞应激程序的能力方面似乎也存在功能差异。这些结果有助于理解 Hsp70 同工型的特异性、它们在应对急性和慢性环境压力方面的共同和独特作用，以及 N. vectensis 种群中局部适应的潜在基础。
