Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.
Key Laboratory for Tobacco Gene Resources, State Tobacco Monopoly Administration, Qingdao, 266101, China.
BMC Plant Biol. 2021 Oct 30;21(1):501. doi: 10.1186/s12870-021-03278-x.
GDSL esterases/lipases are a large protein subfamily defined by the distinct GDSL motif, and play important roles in plant development and stress responses. However, few studies have reported on the role of GDSLs in the growth and development of axillary buds. This work aims to identify the GDSL family members in tobacco and explore whether the NtGDSL gene contributes to development of the axillary bud in tobacco.
One hundred fifty-nine GDSL esterase/lipase genes from cultivated tobacco (Nicotiana tabacum) were identified, and the dynamic changes in the expression levels of 93 of these genes in response to topping, as assessed using transcriptome data of topping-induced axillary shoots, were analysed. In total, 13 GDSL esterase/lipase genes responded with changes in expression level. To identify genes and promoters that drive the tissue-specific expression in tobacco apical and axillary buds, the expression patterns of these 13 genes were verified using qRT-PCR. GUS activity and a lethal gene expression pattern driven by the NtGDSL127 promoter in transgenic tobacco demonstrated that NtGDSL127 is specifically expressed in apical buds, axillary buds, and flowers. Three separate deletions in the NtGDSL127 promoter demonstrated that a minimum upstream segment of 235 bp from the translation start site can drive the tissue-specific expression in the apical meristem. Additionally, NtGDSL127 responded to phytohormones, providing strategies for improving tobacco breeding and growth.
We propose that in tobacco, the NtGDSL127 promoter directs expression specifically in the apical meristem and that expression is closely correlated with axillary bud development.
GDSL 酯酶/脂肪酶是一个由独特的 GDSL 基序定义的大型蛋白质亚家族，在植物发育和应激反应中发挥重要作用。然而，很少有研究报道 GDSL 在腋芽生长和发育中的作用。本研究旨在鉴定烟草中的 GDSL 家族成员，并探讨 NtGDSL 基因是否有助于烟草腋芽的发育。
从栽培烟草（Nicotiana tabacum）中鉴定出 159 个 GDSL 酯酶/脂肪酶基因，利用顶芽处理诱导腋芽的转录组数据分析了其中 93 个基因对顶芽处理的表达水平动态变化。共有 13 个 GDSL 酯酶/脂肪酶基因的表达水平发生变化。为了鉴定驱动烟草顶端和腋芽组织特异性表达的基因和启动子，使用 qRT-PCR 验证了这 13 个基因的表达模式。NtGDSL127 启动子驱动的 GUS 活性和致死基因表达模式在转基因烟草中证实，NtGDSL127 特异性表达于顶端芽、腋芽和花中。NtGDSL127 启动子的三个独立缺失显示，从翻译起始位点上游 235bp 的最小上游片段可以驱动顶端分生组织的组织特异性表达。此外，NtGDSL127 对植物激素有反应，为改善烟草的培育和生长提供了策略。
我们提出，在烟草中，NtGDSL127 启动子特异性地指导顶端分生组织的表达，并且表达与腋芽发育密切相关。
