薰衣草腺毛非特异性脂质转移蛋白nsLTP2介导挥发性有机物的细胞壁转运OA

The fragrance of lavender is primarily derived from volatile organic compounds(VOCs)secreted by the dense glandular trichomes on its surface.These hydrophobic VOCs must traverse the hydrophilic cell wall to be transported from their sites of synthesis to the secretory cavities of the trichomes for storage.However,the specific pathways and mechanisms enabling the efficient transport of hydrophobic VOCs across the hydrophilic cell wall in lavender remain poorly understood.In this study,we conducted a systematic analysis of the types and distribution of trichomes on the upper epidermis of flowers,leaves,and embryos of germinating lavender seeds.Additionally,a non-specific lipid transfer protein gene(nsLTP2)was cloned and subjected to bioinformatic and subcellular localization analyses.The nsLTP2 protein was expressed and purified using Escherichia coli,and its binding affinity for linalool,a major VOC component,was evaluated using a fluorescent probe.The findings revealed that,in addition to peltate glandular trichomes,lavender exhibited two to three morphologically distinct types of capitate glandular trichomes,which differred significantly in structure and distribution.The cloned nsLTP2 gene encoded a protein composed of 115 amino acids,featuring a typical nsLTP domain and eight highly conserved cysteine residues.Gene expression analysis demonstrated that the nsLTP2 gene was predominantly expressed in flowers,with peaked expression observed during the early flowering stage.Subcellular localization analysis indicated that nsLTP2 was localized to the cell wall,and in vitro assays confirmed its ability to bind liposomes.In summary,this study identified nsLTP2 as a critical component in the VOC transport pathway in lavender,facilitating the movement of VOCs through the cell wall.