Cotton(Gossypium hirsutum),serving as a critical raw material for textile manufacturing,is highly vulnerable to drought stress during its growth cycle.Water deficit conditions directly impair boll development and ulti...Cotton(Gossypium hirsutum),serving as a critical raw material for textile manufacturing,is highly vulnerable to drought stress during its growth cycle.Water deficit conditions directly impair boll development and ultimately reduce lint yield.As a crucial unsaturated fatty acid,linolenic acid(C18:3)plays a pivotal role in plant growth and drought response.However,the specific role of C18:3 in drought tolerance and the underlying regulatory network remain largely unelucidated.In this study,drought treatment significantly reduced C18:3 content in cotton leaves,while exogenous application of C18:3 enhanced drought tolerance.Gene expression analysis indicated that the fatty acid desaturase GhFAD3-2 may be involved in the drought-induced reduction of C18:3 content.Overexpression of GhFAD3-2 improved drought tolerance in cotton,whereas silencing GhFAD3-2 decreased drought tolerance,potentially by regulating C18:3,jasmonic acid,and flavonoid metabolism.Further investigation revealed that GhDREB1B acted as an upstream transcriptional activator of GhFAD3-2,directly binding to the promoter of GhFAD3-2 to activate its transcription in response to drought stress in cotton.The expression of GhDREB1B was significantly suppressed under drought stress,and silencing GhDREB1B resulted in decreased GhFAD3-2 expression,reduced C18:3 content,and consequently diminished drought tolerance in cotton.In conclusion,this study elucidates the role of the GhDREB1B-GhFAD3-2 module in regulating C18:3 biosynthesis in response to drought stress in cotton,providing new insights into the molecular mechanisms of drought response and potential breeding targets for cotton.展开更多
基金supported by the National Key Research and Development Program of China(2022YFF1002000)the National Natural Science Foundation of China(32470574)+3 种基金the Xinjiang Production and Construction Corps Key Field ScienceYoung Talent Fund of Xi'an Association for Science and Technology(0959202513012)S&T Program of Hebei(23567601H,24466301D)State Key Laboratory of North China Crop Improvement and Regulation。
文摘Cotton(Gossypium hirsutum),serving as a critical raw material for textile manufacturing,is highly vulnerable to drought stress during its growth cycle.Water deficit conditions directly impair boll development and ultimately reduce lint yield.As a crucial unsaturated fatty acid,linolenic acid(C18:3)plays a pivotal role in plant growth and drought response.However,the specific role of C18:3 in drought tolerance and the underlying regulatory network remain largely unelucidated.In this study,drought treatment significantly reduced C18:3 content in cotton leaves,while exogenous application of C18:3 enhanced drought tolerance.Gene expression analysis indicated that the fatty acid desaturase GhFAD3-2 may be involved in the drought-induced reduction of C18:3 content.Overexpression of GhFAD3-2 improved drought tolerance in cotton,whereas silencing GhFAD3-2 decreased drought tolerance,potentially by regulating C18:3,jasmonic acid,and flavonoid metabolism.Further investigation revealed that GhDREB1B acted as an upstream transcriptional activator of GhFAD3-2,directly binding to the promoter of GhFAD3-2 to activate its transcription in response to drought stress in cotton.The expression of GhDREB1B was significantly suppressed under drought stress,and silencing GhDREB1B resulted in decreased GhFAD3-2 expression,reduced C18:3 content,and consequently diminished drought tolerance in cotton.In conclusion,this study elucidates the role of the GhDREB1B-GhFAD3-2 module in regulating C18:3 biosynthesis in response to drought stress in cotton,providing new insights into the molecular mechanisms of drought response and potential breeding targets for cotton.
