JAZ家族基因在采后黄瓜低温贮藏条件下的表达分析

Expression analysis of JAZ family genes in harvested cucumber fruit under cold storage condition

冷害是限制采后黄瓜低温贮运的主要问题,茉莉酸(jasmonic acid, JA)在植物抗冷性调控中具有重要作用,JAZ(JA ZIM-domain)蛋白是JA信号的转录阻遏物,抑制JA合成和信号传递。为探究JAZ家族基因在采后黄瓜低温贮藏期间的作用,从黄瓜基因组中筛选鉴定了JAZ家族基因,并分析了该家族基因的序列特征、理化性质和时空表达模式。结果显示,黄瓜基因组中共鉴定到了17个JAZ基因,可分为8个亚家族,蛋白序列中均含有Tify或CCT保守结构域。绝大多数的JAZ基因响应贮藏低温(5℃和10℃)处理,说明JAZ家族蛋白参与采后黄瓜耐冷性调控,但不同JAZ基因对低温处理的响应强度有差异。黄瓜JAZ家族基因的启动子含有丰富的逆境响应元件,但具体的元件类型存在差异。14个JAZ基因的表达量在5℃贮藏期间逐渐下降,但JAZ11表达随贮藏时间显著增加。外源脱落酸(abscisic acid, ABA)、茉莉酸甲酯(methyl jasmonate, MeJA)和褪黑素(melatonin, MT)处理,以及采后黄瓜中沉默HHO2和GRP3表达显著影响冷藏黄瓜JAZ家族基因的表达,再次证明黄瓜JAZ家族基因参与采后黄瓜耐冷性的调控。ABA、MeJA和MT处理显著下调JAZ11表达,沉默HHO2和GRP3显著上调JAZ11表达,证明JAZ11负调控JA信号和采后黄瓜耐冷性。该研究明确了黄瓜JAZ家族基因的理化性质和在低温下的表达模式,表明JAZ11可能是JAZ家族蛋白中负调控采后黄瓜耐冷性的主效因子。

Chilling injury poses a significant challenge to the postharvest storage and transportation of cucumber fruits.Jasmonic acid(JA)plays a crucial role in regulating the chilling resistance in plants.JAZ(JA ZIM-domain)proteins act as transcription repressors of JA signaling,inhibiting both the synthesis and transmission of JA.To explore the role of JAZ family genes during cold storage of harvested cucumber fruits,JAZ family genes were identified and screened from the cucumber genome,and their sequence features,physicochemical properties,and spatial-temporal expression patterns were analyzed.The findings revealed a total of 17 JAZ genes in the cucumber genome,which could be divided into 8 subfamilies,all containing the conserved Tify or CCT domains in their protein sequences.Most of these JAZ genes responded to cold storage(5℃and 10℃)treatments,suggesting the involvement of JAZ family proteins in regulating the chilling tolerance in cucumber fruits.However,different JAZ genes exhibited varying degrees of response to cold treatments.The promoters of cucumber JAZ family genes had numerous stress-responsive elements,though the specific types of elements varied.During 5℃storage period,the expression levels of 14 JAZ genes gradually decreased,while the expression of JAZ 11 significantly increased with storage time.Exogenous treatments with abscisic acid(ABA),methyl jasmonate(MeJA),melatonin(MT),as well as the silencing HHO 2 and GRP 3 expression in harvested cucumbers,significantly impacted the expression of JAZ family genes.These results further confirmed the involvement of cucumber JAZ family genes in regulating chilling tolerance.ABA,MeJA,and MT treatments significantly downregulated JAZ 11 expression,whereas silencing HHO 2 and GRP3 significantly upregulated its expression.These results together suggest that JAZ11 negatively regulates JA signaling and cold tolerance in cucumber fruits.This study provides novel insights into the physicochemical properties and expression patterns of cucumber JAZ family genes under cold conditions,and suggesting that JAZ11 may be the key factor responsible for negative regulation of chilling tolerance in harvested cucumbers among JAZ family proteins.