State Key Laboratory of Crop Stress Biology in Arid Areas, College of Life Sciences, Northwest A&F University, Yangling 712100, China.
College of Horticulture, Northwest A&F University, Yangling 712100, China.
J Plant Physiol. 2019 Mar-Apr;234-235:117-132. doi: 10.1016/j.jplph.2019.02.005. Epub 2019 Feb 13.
The GASA (GA-stimulated Arabidopsis) gene family is highly specific to plants, signifying a crucial role in plant growth and development. Herein, we retrieved 119 GASA genes in 10 different plant species in two major lineages (monocots and eudicots). Further, in the phylogenetic tree we classified these genes into four well-conserved subgroups. All the proteins contain a conserved GASA domain with similar characteristics and a highly specific 12-cysteine residue of the C-terminus position. According to the global microarray data and qRT-PCR based analysis, the OsGASA gene family was dominantly expressed in the seedling and transition phase of floral stages. Despite this, OsGASA genes profoundly contribute to rice grain size and length, whereas the highest abundance of transcript level was noticed in stage-2 (Inf 6, 3.0-cm-long spikelet) and stage-3 (Inf 7, 5.0-cm-long spikelet) under GA treatment during panicle formation. Additionally, the maximum expression level of these genes was recorded in response to GA and ABA in young seedlings. Further, in response to abiotic stresses, OsGASA1/8/10 was up- regulated by salt, OsGASA2/5/7 by drought, OsGASA3/6 by cold, and OsGASA4/9 by heat stress. With the exception of OsGASA4, the higher transcription levels of all the other GASA genes were induced by Cd and Cr metal stresses (8-10 fold changes) at various time points. Finally, the GO ontology analysis of GASAs revealed the biological involvement in the GA-mediated signaling pathway and abiotic stresses. Prominently, most of these proteins are localized in cellular components such as the cell wall and extracellular region, where the molecular functions such as ATP binding and protein binding were observed. These results imply that GASAs are significantly involved in rice panicle developmental stages, responses to external stimuli, and hormones.
GASA（GA 刺激的拟南芥）基因家族在植物中高度特异，表明其在植物生长和发育中具有重要作用。在此，我们从两个主要谱系（单子叶植物和双子叶植物）的 10 种不同植物中检索到 119 个 GASA 基因。此外，在系统发育树中，我们将这些基因分为四个高度保守的亚组。所有蛋白质都含有保守的 GASA 结构域，具有相似的特征，并且在 C 末端位置具有高度特异的 12 个半胱氨酸残基。根据全局微阵列数据和基于 qRT-PCR 的分析，OsGASA 基因家族在幼苗和花阶段的过渡阶段中大量表达。尽管如此，OsGASA 基因对水稻粒长和粒宽有深远的贡献，而在 GA 处理期间，在穗形成过程中，转录水平的最高丰度在阶段 2（Inf6，3.0 厘米长的小穗）和阶段 3（Inf7，5.0 厘米长的小穗）中被观察到。此外，在幼株中，这些基因对 GA 和 ABA 的响应表现出最大的表达水平。此外，在非生物胁迫下，OsGASA1/8/10 被盐上调，OsGASA2/5/7 被干旱上调，OsGASA3/6 被冷上调，OsGASA4/9 被热应激上调。除了 OsGASA4 之外，所有其他 GASA 基因的转录水平在不同时间点都被 Cd 和 Cr 金属胁迫（8-10 倍变化）上调。最后，GASAs 的 GO 本体分析揭示了它们在 GA 介导的信号通路和非生物胁迫中的生物学参与。突出的是，这些蛋白质中的大多数定位于细胞壁和细胞外区域等细胞成分中，在这些位置观察到了 ATP 结合和蛋白质结合等分子功能。这些结果表明，GASAs 显著参与了水稻穗发育阶段、对外界刺激的响应以及激素的作用。
