Protease inhibitor ASP enhances freezing tolerance by inhibiting protein degradation in kumquat  

作　　者：Hua Yang Ke-wei Qiao Jin-jing Teng Jia-bei Chen Ying-li Zhong Li-qun Rao Xing-yao Xiong Huang Li 

机构地区：[1]College of Bioscience and Biotechnology,Hunan Agricultural University,Changsha 410128,China [2]Hunan Provincial Key Laboratory for Germplasm Innovation and Crop Utilization,Hunan Agricultural University,Changsha 410128,China [3]Agricultural Genomics Institute at Shenzhen,Chinese Academy of Agricultural Sciences,Shenzhen 518000,China [4]Center for Plant Science Innovation,University of Nebraska-Lincoln,Lincoln,NE 68588,USA

出　　处：《Horticulture Research》2023年第4期53-62,共10页园艺研究（英文）

基　　金：sponsored by the National Natural Science Foundation of China(No.31200963);the Key Project of Hunan Provincial Education Department(No.18A091).

摘　　要：Cold acclimation is a complex biological process leading to the development of freezing tolerance in plants.In this study,we demonstrated that cold-induced expression of protease inhibitor FmASP in a Citrus-relative species kumquat[Fortunella margarita(Lour.)Swingle]contributes to its freezing tolerance by minimizing protein degradation.Firstly,we found that only cold-acclimated kumquat plants,despite extensive leaf cellular damage during freezing,were able to resume their normal growth upon stress relief.To dissect the impact of cold acclimation on this anti-freezing performance,we conducted protein abundance assays and quantitative proteomic analysis of kumquat leaves subjected to cold acclimation(4◦C),freezing treatment(−10◦C)and post-freezing recovery(25◦C).FmASP(Against Serine Protease)and several non-specific proteases were identified as differentially expressed proteins induced by cold acclimation and associated with stable protein abundance throughout the course of low-temperature treatment.FmASP was further characterized as a robust inhibitor of multiple proteases.In addition,heterogeneous expression of FmASP in Arabidopsis confirmed its positive role in freezing tolerance.Finally,we proposed a working model of FmASP and illustrated how this extracellular-localized protease inhibitor protects proteins from degradation,therebymaintaining essential cellular function for post-freezing recovery.These findings revealed the important role of protease inhibition in freezing response and provide insights on how this role may help develop new strategies to enhance plant freezing tolerance.

关 键 词：FREEZING INHIBITING thereby 

分 类 号：S666.2[农业科学—果树学]