Strigolactones (SLs) are the major plant hormones that play important roles in regulating organ development and environmental stress tolerance in plants. Even though the SL-related genes have been identified and well characterized in some plants, the information of SL-related genes in soybean is not fully established yet, especially in response to salt and alkaline stresses. In this study, we identified nine SL biosynthetic genes that include two D27, two CCD7, two CCD8, and three MAX1, as well as seven SL signaling genes that comprised two D14, two MAX2, and three D53 in the soybean genome. We found that SL biosynthetic and signaling genes are evolutionary conserved among different species. Syntenic analysis of these genes revealed their location on nine chromosomes as well as the presence of 10 pairs of duplication genes. Moreover, plant hormone and stress-responsive elements were identified in the promoter regions of SL biosynthetic and signaling genes. By using reverse transcription quantitative real-time PCR, we confirmed that SL genes have different tissue expressions in roots, stems, and leaves. The expression profile of SL biosynthetic and signaling genes under salt and alkaline stresses further confirmed the regulatory roles of SL biosynthetic and signaling genes under stress. In conclusion, we identified and provided valuable information on the soybean SL biosynthetic and signaling genes, and established a foundation for further functional analysis of soybean SL-related genes in response to salt and alkaline stresses.

中文翻译：

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大豆（Glycine max）响应盐和碱胁迫的独脚金内酯生物合成和信号基因的鉴定和表达分析。


独脚金内酯（SL）是主要的植物激素，在调节植物器官发育和环境胁迫耐受性方面发挥着重要作用。尽管在一些植物中已鉴定并充分表征了 SL 相关基因，但大豆中 SL 相关基因的信息尚未完全确定，特别是在响应盐和碱胁迫方面。在这项研究中，我们在大豆基因组中鉴定了九个SL生物合成基因，包括两个D27、两个CCD7、两个CCD8和三个MAX1，以及七个SL信号基因，包括两个D14、两个MAX2和三个D53。我们发现SL生物合成和信号基因在不同物种之间是进化保守的。对这些基因的同线性分析揭示了它们在 9 条染色体上的位置以及 10 对重复基因的存在。此外，在 SL 生物合成和信号基因的启动子区域还鉴定出了植物激素和胁迫响应元件。通过逆转录实时定量PCR，我们证实SL基因在根、茎、叶中具有不同的组织表达。盐和碱胁迫下SL生物合成和信号基因的表达谱进一步证实了SL生物合成和信号基因在胁迫下的调控作用。总之，我们鉴定并提供了有关大豆 SL 生物合成和信号基因的有价值的信息，为进一步分析大豆 SL 相关基因响应盐和碱胁迫的功能奠定了基础。