RUI: Characterizing Protein Homeostasis and the Regulatory Mechanisms Controlling Molecular Chaperone Expression in the Highly Stenothermal Notothenioid Fish, Trematomus Bernacchii

该项目将综合对鱼类生理、蛋白质生产和遗传学的分析，以确定南大洋中的关键鱼种(伯氏吸虫)是否永久失去了对分子伴侣(一类促进蛋白质在细胞中适当折叠的蛋白质)的调节。为此，将努力分析这些鱼类中的伴侣蛋白，以及高温如何影响蛋白质周转和蛋白质损伤。这些研究应该更明确地确定伴侣功能的中断是环境控制的(这可能表明这些鱼可能以某种形式受益于海洋表面温度的上升)，或者是否由于进化过程中其结构的变化而完全丧失伴侣功能(这表明这些鱼不太可能能够适应变暖)。除了填补我们在南大洋鱼类多样性和进化以及温度变化可能对鱼类种群产生的潜在影响方面的关键知识空白外，该项目还将支持瑞安研究所对本科生和研究生的培训。具体地说，与该项目目标直接相关的活动和内容将被纳入索诺马州立大学的本科课程，以努力增加本科生对研究的参与，特别是对代表性不足的群体。该项目的具体目标是对核苷酸差异导致的跨调控元件的非同义氨基酸变化进行比较分析，即在T.bernacchii和N.angustata中，即热休克因子(HSF)转录因子家族的成员。该项目还将利用从分离的肝细胞中新合成的蛋白质的代谢标记来监测长期驯化于-1.5℃和+4℃的鱼类的蛋白质周转率。将在多个组织中量化伴随能力和受损蛋白质水平的变化，以更好地了解在+4℃长期驯化下维持蛋白质稳态的细胞需求。结合起来，这项工作将有助于回答有关这些鱼类分化的问题，以及关于蛋白质结构和功能的基本信息，这些信息也可能具有生物医学意义。

The project will integrate analyses of fish physiology, protein production and genetics to determine if regulation of molecular chaperones (a class of proteins that facilitate the proper folding of proteins in a cell) has been permanently lost in a key fish species (Trematomus bernacchii) inhabiting the Southern Ocean. To do so, efforts will be undertaken to analyze chaperones in these fishes and how elevated temperatures impact protein turnover and protein damage. These studies should more definitively determine if the interruption of chaperone function is environmentally controlled (which could suggest these fish could benefit in some form by increasing sea surface temperatures) or if there is complete loss of chaperone function due to a change in its structure through evolutionary processes (which would suggest these fish are less likely to be able to adapt to warming). In addition to filling key gaps in our knowledge about the diversity and evolution of fishes in the southern ocean and the potential impacts changing temperatures might have on fish populations, the project will support the training of undergraduate and graduate students at an RUI institution. Specifically, activities and content directly related to this project's aims will be incorporated into the undergraduate curriculum at Sonoma State University in an effort to increase undergraduate participation in research, especially with respect to underrepresented groups.The project has specific aims to perform a comparative analysis of nucleotide divergence resulting in non-synonymous amino acid changes in the trans-regulatory elements, namely members of the heat shock factor (HSF) family of transcription factors, in T. bernacchii and N. angustata. The project will also utilize metabolic labeling of newly synthesized proteins from isolated hepatocytes to monitor protein turnover rates in fish acclimated to both -1.5 and +4 °C for an extended period. Changes in chaperoning capacity and levels of damaged proteins will be quantified in multiple tissues to gain a better understanding of the cellular requirements for maintaining protein homeostasis under long-term acclimations to +4 °C. In combination, the work will help answer questions regarding divergence in these fishes as well a fundamental information regarding protein structure and function that may also have bio-medical implications.