Studies on Hemolymph Ice Nucleator Involved in Insect Cold Tolerance

冰核物质在高于正常情况下形成冰的温度时开始结冰，已成为从大气科学到农业(冰核细菌对作物造成的损害)到低温保存等广泛科学学科的重要研究课题。我们研究了具有冰核活性的血液蛋白的生物学和生化，这些蛋白是某些昆虫在体液冻结中生存能力的重要组成部分。据推测，成核剂在组织中形成冰之前在血液中形成冰，从而促进细胞内过冷状态的形成和防止细胞中冰晶体的形成。该项目继续这些研究，并特别关注三叶鹤耐寒幼虫产生的血脂蛋白。主要的研究工作集中在是什么使这种脂蛋白成为冰核。脂蛋白非常有趣，因为它在组成上与细菌冰核蛋白有一定的相似之处，细菌冰核蛋白参与了对某些农作物的严重冻害。总体而言，这些结果应该会增加我们对昆虫耐寒性和耐冻性调节的理解。

Ice nucleators, which initiate ice formation at temperatures above those at which ice formation would normally occur, have become important research topics in a wide range of scientific disciplines ranging from atmospheric science to agriculture (crop damage resulting from ice nucleating bacteria) to cryopreservation. We have studied the biology and biochemistry of blood proteins with ice nucleator activity that are important components of the ability of certain insects to survive the freezing of their body fluids. It has been postulated that the nucleators cause ice formation in the blood prior to ice formation in the tissue thereby facilitating formation of a supercooled state within the cells and a prevention of ice crystal formation in the cells. This project continues those studies and is particularly concerned with blood lipoproteins produced by freeze tolerant larvae of the cranefly Tipula trivittata. The major research effort focuses on what makes this lipoprotein an ice nucleator. The lipoprotein is quite interesting because of certain similarities in composition with the bacterial ice nucleator which is involved in serious freeze related damage to certain agricultural crops. Overall, the results should increase our understanding of the regulation of cold-hardiness and freeze tolerance in insects.