熱休克蛋白在作物的逆境反應與採收後處理中扮演的角色

Heat Shock Proteins in Stress Response and Postharvest Handling of Crops

熱休克蛋白為高度保守的分子伴護蛋白質，在原核及真核細胞中皆有表現，主要功能為協助蛋白質折疊，維持細胞正常機能。熱休克蛋白因最初被發現其受高溫誘導的特性而得名，後續研究發現其在植物中亦受低溫、失水、高鹽、黑暗、紫外光等環境逆境及病蟲害感染等生物逆境誘導，並直接影響植物對逆境的耐抗性。在園藝作物採後處理操作中，實施包括熱處理在內的逆境，是提高產品貯運耐受性的常用方法。例如在芒果與木瓜檢疫前，以相對較低的溫度進行預熱，能有效降低檢疫造成的生理障礙；另外在香蕉、鳳梨、草莓、番茄、辣椒等園藝作物的研究中，熱處理可減緩低溫貯藏造成的寒害。一般認為熱休克反應，為逆境處理提高植物抵抗力關鍵之一。植物熱休克蛋白與熱休克反應相關研究已逐漸完善，本文整理近年植物熱休克蛋白的相關基礎研究與在作物中應用的研究成果，探討直接調控熱休克反應路徑，取代熱處理或逆境處理的可行性與需注意的要點。

Heat shock proteins (HSPs) are highly conserved molecular chaperones in prokaryotic and eukaryotic cells. HSPs coordinate the correct folding of substrate proteins and play critical roles in maintaining normal cellular functions. HSPs are induced by both abiotic and biotic stress such as heat and insect attack and confer stress tolerance and pathogen resistance in plants. In postharvest handling of crops, moderate stress is applied, such as the heat increase of crops resistance to stressful operations and disinfection through heat or cold storage. Induction of heat shock response (HSR) is one of the key processes to the enhancement of stress tolerance. The regulatory pathway of HSR and the functions of HSP have been extensively studied in plants. In this review, I summarized recent advances in HSP and HSR in plants and the corresponding applications in crops. Furthermore, the potential of developing new postharvest technologies by directly targeting the activation of the HSR pathway is also examined.