CCaP1/CCaP2/CCaP3 interact with plasma membrane H^(+)-ATPases and promote thermoresponsive growth by regulating cell wall modification in Arabidopsis  

作　　者：Jing-Jing Wang Juan Gao Wei Li Jian-Xiang Liu 

机构地区：[1]State Key Laboratory of Plant Environmental Resilience,College of Life Sciences,Zhejiang University,Hangzhou 310027,China [2]College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310027,China

出　　处：《Plant Communications》2024年第7期90-105,共16页植物通讯（英文）

基　　金：supported by a grant from the National Natural Science Foundation of China(31872653).

摘　　要：Arabidopsis plants adapt to warm temperatures by promoting hypocotyl growth primarily through the basic helix-loop-helix transcription factor PIF4 and its downstream genes involved in auxin responses,which enhance cell division.In the current study,we discovered that cell wall-related calcium-binding protein 2(CCaP2)and its paralogs CCaP1 and CCaP3 function as positive regulators of thermo-responsive hypocotyl growth by promoting cell elongation in Arabidopsis.Interestingly,mutations in CCaP1/CCaP2/CCaP3 do not affect the expression of PIF4-regulated classic downstream genes.However,they do noticeably reduce the expression of xyloglucan endotransglucosylase/hydrolase genes,which are involved in cell wall modification.We also found that CCaP1/CCaP2/CCaP3 are predominantly localized to the plasma membrane,where they interact with the plasma membrane H^(+)-ATPases AHA1/AHA2.Furthermore,we observed that vanadate-sensitive H^(+)-ATPase activity and cell wall pectin and hemicellulose contents are significantly increased in wild-type plants grown at warm temperatures compared with those grown at normal growth temperatures,but these changes are not evident in the ccap1-1 ccap2-1 ccap3-1 triple mutant.Overall,our findings demonstrate that CCaP1/CCaP2/CCaP3 play an important role in controlling thermo-responsive hypocotyl growth and provide new insights into the alternative pathway regulating hypocotyl growth at warm temperatures through cell wall modification mediated by CCaP1/CCaP2/CCaP3.

关 键 词：AHA1/AHA2 CCaP1/CCaP2/CCaP3 cell wall modification hypocotyl growth thermomorphogenesis warm temperature 

分 类 号：Q94[生物学—植物学]