The molecular analysis of low temperature and freezing stress resistance

一些鱼类和昆虫通过制造冰结合蛋白质来保护自己不被冻结，这些蛋白质粘在胚胎冰晶上，并通过阻止更多的水分子的加入来阻止冰的生长。因此，这些蛋白质显著降低冷冻温度。然而，冰结合蛋白也被发现，但鲜为人知的是，在一些生物体中，如植物，昆虫和细菌，即使它们被冷冻也能存活。该提案首先试图测试冰结合蛋白是否对生存至关重要，这是以前从未做过的事情。进一步的研究将确定耐冷冻生物体中的蛋白质是否能抵御低温病原体，以及它们是否能在低温下帮助保护宿主细胞膜。这些来自耐冻生物的蛋白质的特殊性质，包括（有点讽刺的是）它们不能显著降低冰点，使它们对理解冰结合的机制特别有用。这是不容易做到的事情，更好地了解，更活跃的蛋白质从物种，不冻结。加拿大的地理和粮食安全要求，在未来，作物将不得不种植更北，因此，抗冻性的转移将有经济效益。同样，这些蛋白质具有用于组织冷冻保存的医学应用。我们发现，冰结合蛋白可以抑制天然气和石油勘探和运输过程中自发形成的危险气体水合物（带来灾难性后果），这意味着未来，基于这些蛋白质的材料的合理设计将直接有益于许多加拿大人的健康和安全。这一关于低温和冷冻应激抗性的分子分析的研究计划是专门为学生的教学而设计的，并将吸引那些想要解决他们认为相关和引人注目的问题的年轻学员。

Some fish and insects are protected from freezing by making ice-binding proteins that stick to embryonic ice crystals and prevent ice growth by blocking the addition of more water molecules. Thus, these proteins significantly lower the freezing temperature. However, ice-binding proteins are also found, but little known, in a few organisms such as plants, insects and bacteria that survive even if they are frozen. This proposal first seeks to test if ice-binding proteins are vital for survival, something that has never been done before. Further investigations will determine if the proteins in freeze-tolerant organisms defend against low-temperature pathogens, and if they can help protect host cell membranes at low temperatures. The special properties of these proteins from freeze-tolerant organisms, including (somewhat ironically) their inability to significantly depress the freezing point, makes them especially useful for understanding the mechanisms of ice binding. This is something that cannot be done so easily with the better known, more active proteins from species that do not freeze. Canada's geography and food security demands that in the future, crops will have to be grown further north and so the transfer of freeze-tolerance will have economic benefits. As well, these proteins have medical applications for tissue cryopreservation. Our discovery that ice-binding proteins inhibit dangerous gas hydrates that spontaneously form during gas and oil exploration and transport (with disastrous consequences) means that in the future, the rational design of materials based on these proteins will directly benefit the health and safety of many Canadians. This research program on the molecular analysis of low temperature and freezing stress resistance has been specifically designed for instruction of students and will appeal to young trainees who want to address problems that they see as relevant and compelling.