Structure/Function Studies of Antifreeze Protein From the Beetle Dendroides canadensis

9808376 Duman抗冻蛋白（AFP）现已在许多变温（冷血）动物和植物中鉴定。 在某些昆虫中发现了最活跃的AFP，例如甲虫Dendroides canadensis的越冬幼虫。 Duman博士已经纯化并鉴定了其中几种蛋白质，并使用重组DNA技术从该物种中克隆了13种类似的AFP。 本研究将继续探索D. canadensis AFPs. 此外，将确定13种不同甲虫AFP中的各种结构差异转化为AFP降低血淋巴冰点、防止由外部冰跨越昆虫表面引发的冻结和/或促进过冷的能力的功能变化的可能性。 甲虫AFP的抗冻活性的某些方面可以通过某些蛋白质和低分子量溶质如琥珀酸盐而显著增加。 将研究这些增强剂的机制，以了解如何优化AFP的活性。 这些研究所提供的信息将直接影响到这些极其活跃的AFP的许多潜在应用，例如昆虫AFP基因在植物中的表达。

9808376 Duman Antifreeze proteins (AFPs) have now been identified in a number of poikilothermic (cold blooded) animals and plants. The most active AFPs are found in certain insects, such as the overwintering larvae of the beetle Dendroides canadensis. Dr. Duman has purified and characterized several of these proteins, and using recombinant DNA techniques he has cloned 13 similar AFPs from this species. The studies in this proposal will continue to ascertain the relationship between the structure and antifreeze function of the D. canadensis AFPs. Also, the possibility that various structural differences in the 13 different beetle AFPs translate into functional variation in abilities of the AFPs to lower the freezing point of the hemolymph, prevent freezing initiated by outside ice across the surface of the insect, and/or promote supercooling will be determined. Certain aspects of the antifreeze activity of the beetle AFPs can be substantially increased by certain protein and low molecular weight solutes such as succinate. The mechanism of these enhancers will be investigated to understand how to optimize the activity of the AFPs. Information provided by these studies will have a direct bearing on the numerous potential applications of these extremely active AFPs, such as expression of the insects AFP genes in plants.