Synchronous and timely regulation of multiple genes results in an effective defense response that decides the fate of the host when challenged with pathogens or unexpected changes in environmental conditions. One such gene, which is downregulated in response to multiple bacterial pathogens, is a putative nonspecific lipid transfer protein (nsLTP) of unknown function that we have named DISEASE RELATED NONSPECIFIC LIPID TRANSFER PROTEIN 1 (DRN1). We show that upon pathogen challenge, DRN1 is strongly downregulated, while a putative DRN1-targeting novel microRNA (miRNA) named DRN1 Regulating miRNA (DmiR) is reciprocally upregulated. Furthermore, we provide evidence that DRN1 is required for defense against bacterial and fungal pathogens as well as for normal seedling growth under salinity stress. Although nsLTP family members from different plant species are known to be a significant source of food allergens and are often associated with antimicrobial properties, our knowledge on the biological functions and regulation of this gene family is limited. Our current work not only sheds light on the mechanism of regulation but also helps in the functional characterization of DRN1, a putative nsLTP family member of hitherto unknown function.

多个基因的同步及时调节可产生有效的防御反应，从而在受到病原体或环境条件意外变化的挑战时决定宿主的命运。响应多种细菌病原体而被下调的一个这样的基因是功能未知的推定非特异性脂质转移蛋白（nsLTP），我们将其命名为DISEASE相关非特异性脂质转移蛋白1（DRN1）。我们发现，当病原体攻击，DRN1强烈下调，而假定DRN1-目标命名新微RNA（miRNA）DRN1调节的miRNA（DMIR）往复地上调。此外，我们提供证据表明DRN1是防御细菌和真菌病原体以及盐分胁迫下正常幼苗生长所必需的。尽管已知来自不同植物物种的nsLTP家族成员是食物过敏原的重要来源，并且通常与抗菌特性有关，但是我们对这一基因家族的生物学功能和调控的了解有限。我们当前的工作不仅阐明调节机制，而且有助于DRN1的功能表征，DRN1是迄今未知功能的推定nsLTP家族成员。