Abstract：[Objective]Thisstudyaimedtoexplorethebiologicalfunctionsofoneof thealuminum-activatedmalate transporter （ALMT）familygenes，GhALMT10，inthedroughtresistanceofcoton，therebyestablishingafoundation foradeeper understandingof themechanisms ofdroughtresistance incoton．[Methods]ThecodingsequenceofGhALMT10 gene was amplifiedfromGossypiumhirsutumTM-1bypolymerasechainreaction （PCR），followedbybioinformaticsanalysis.The expresionpattensofthisgneinvariouscotontissuesaswellasunderdroughtstress，wereassessedusingquantitative real-timePCR（qRT-PCR）.Aditionally，thebiological functionof thisgeneincoton'sresponsetodrought stress was preliminarilyverifiedusingvirus-induced gene silencing（VIGS）technology.[Results]Thecodingregionof GhALMT0spans 1 401bp，encoding aproteincomposed of 466aminoacid residues，which is predicted to be stableand hydrophobic. Phylogeneticanalysisindicated that GhALMT10 iscloselyrelatedto GrALMT10，GaALMT10-like，HsALMT10，and TcALMT10.Results byqRT-PCR indicated thatGhALMT10is expressed incotonroots，stems，and leaves，withthe highest expresion levelobservedin theroots.Comparedwiththecontroltreatment withclear water，theexpresionlevelofGhALMT10 was low at ^3h of drought sress，and then significantly increased at 6n and9h of drought stress treatment，while it significantly decreased at 24h Furthermore，thesurvival rateofGhALMT10-silenced cotton plants was significantly higher under drought stresscomparedwith thenegativecontrolplants.Thewaterlossrateof detached leaveswassignificantlyreduced，the chloropyll content in leavesafterdroughttreatmentwas significantly increased，and themalondialdehydecontentwas significantlydecreased inGhALMT10-silencedcoton plants.[Conclusion]Thedrought toleranceof GhALMT10-silenced plants Was significantlyenhanced，indicating that GhALMT10gene negativelyregulates droughtresistance incotton.

Keywords：cotton;GhALMO;drought stress;expressonpaternanalysis;virus-inducedgenesilencing;physiologcaland biochemical indicators

棉花是我国重要的经济作物。新疆是我国最大的棉花种植基地，但新疆的地理位置在很大程度上决定了其干旱的环境1。干旱胁迫会导致棉花的产量和纤维品质降低[2-3]。因此，培育抗旱棉花品种显得尤为重要。而传统杂交育种技术存在耗时长、难度大等固有局限。通过对棉花干旱相关基因展开深入探究，解析棉花抗旱的分子机理，并借助分子育种手段培育抗旱棉花新品系，无疑是解决该问题的1条理想路径。

铝激活苹果酸转运蛋白（aluminium-activatedmalatetransporter，ALMT）在植物体内发挥着多种功能，包括参与调节阴离子稳态[45]、矿物质营养元素吸收、气孔开闭、对铝（aluminium，Al）的耐受性[89]和果实酸度等。第1个被发现的ALMT家族成员是TaALMT1，该基因编码的蛋白可被 Al³⁺ 激活，调控苹果酸从小麦的根部分泌至土壤，并且过表达该基因可以提高小麦对Al胁迫的耐受性[1I-13]。拟南芥ALMT家族基因有14个成员，它们定位在不同的组织细胞中且发挥着不同的功能[14]。如AtALMT1在根部的表达可以及时调节苹果酸分泌，从而在根部与 Al³⁺ 发生螯合反应，减轻A1胁迫对根部的损伤[15]。AtALMT4基因不仅通过脱落酸（abscisicacid，ABA）信号通路调节气孔开度，还在花粉管中表达，通过调节细胞pH或膨压影响受精过程1。AtALMT6主要在保卫细胞和花器官中表达，编码的蛋白定位于液泡膜，液泡pH和胞质苹果酸可调节其活性，进而影响苹果酸的转运，Atalmt6基因敲除植物的保卫细胞液泡中苹果酸含量降低[17]。AtALMT9在气孔开放过程中起关键作用，功能缺失突变体气孔开放受损，蒸腾作用减弱，比野生型更耐旱[18]。……