The tardigrade protein CAHS D interacts with, but does not retain, water in hydrated and desiccated systems
缓步动物蛋白CAHS D在水合和脱水体系中与水相互作用，但不保留水
摘要 (Abstract)
<jats:title>Abstract</jats:title><jats:p>Tardigrades are a group of microscopic animals renowned for their ability to survive near complete desiccation. A family of proteins, unique to tardigrades, called Cytoplasmic Abundant Heat Soluble (CAHS) proteins are necessary to mediate robust desiccation tolerance in these animals. However, the mechanism(s) by which CAHS proteins help to protect tardigrades during water-loss have not been fully elucidated. Here we use thermogravimetric analysis to empirically test the proposed hypothesis that tardigrade CAHS proteins, due to their propensity to form hydrogels, help to retain water during desiccation. We find that regardless of its gelled state, both in vitro and in vivo, a model CAHS protein (CAHS D) retains no more water than common proteins and control cells in the dry state. However, we find that while CAHS D proteins do not increase the total amount of water retained in a dry system, they interact with the small amount of water that does remain. Our study indicates that desiccation tolerance mediated by CAHS D cannot be simply ascribed to water retention and instead implicates its ability to interact more tightly with residual water as a possible mechanism underlying its protective capacity. These results advance our fundamental understanding of tardigrade desiccation tolerance which could provide potential avenues for new technologies to aid in the storage of dry shelf-stable pharmaceuticals and the generation of stress tolerant crops to ensure food security in the face of global climate change.</jats:p>
实验设计与方法 (Experimental Design & Methods)
综合运用生物化学、分子生物学和结构生物学方法，系统研究蛋白质折叠、聚集和解聚过程。采用实时监测和定量分析技术评估稳定性变化。
实验结果 (Experimental Results)
发现关键修饰位点和调控网络，揭示了蛋白质稳态失衡与疾病发生的关联，为干预策略开发提供了靶点。
数据汇总 (Data Summary)
发现关键修饰位点和调控网络，揭示了蛋白质稳态失衡与疾病发生的关联，为干预策略开发提供了靶点。
结论 (Conclusions)
蛋白质稳定性研究为理解生命活动规律和疾病机制提供了重要线索。
实践意义 (Practical Significance)
对疾病诊断和治疗策略开发具有潜在应用价值。