苜蓿(MedicagoL.)是一种具有耐盐性的优质多年生豆科牧草,割草公差,蛋白质含量高,和其他有经济价值的特征。作为第六类植物激素,油菜素类固醇(BRs)在调节多种植物生长中起着不可或缺的作用,成熟,和环境适应过程,从而影响植物的扩张和发育。油菜素类固醇信号激酶(BSKs)是BR信号转导通路下游的关键胞质受体激酶,参与植物生长,发展,和压力调节。然而,5种苜蓿中BSK基因家族的系统发育和表达模式分析很少有报道;在这项研究中,在五个亚种的基因组中发现了52个BSK家族成员,根据蛋白质序列构建系统发育树,允许我们将所有BSKs分为七个不同的组。域,保守的图案,外显子-内含子结构分析表明,大多数BSK成员相对保守,MtBSK3-2、MtBSK7-1和MtBSK7-2除外,它们可能是截断的成员。种内共线性和Ka/Ks分析表明,纯化选择在进化过程中会影响BSK基因;启动子区域中的大多数顺式作用元件与反应有关,如光,防御,和压力,厌氧诱导,MeJA,和脱落酸。表达模式分析表明,大多数苜蓿基因在用250mMNaCl处理后0.5小时达到峰值后表现出下调,特别是对于MsBSK14、MsBSK15、MsBSK17、MsBSK19和MsBSK21;同时,MsBSK4、MsBSK7和MsBSK9在12h时增加并高表达,在盐胁迫下表现出显著改变的表达模式;此外,MsBSK4、MsBSK7和MsBSK9在叶片中表现出特异性表达。qRT-PCR分析证实MsBSK4、MsBSK7、MsBSK9、MsBSK14、MsBSK15和MsBSK16的表达趋势与转录组数据匹配。然而,MsBSK17、MsBSK19和MsBSK21的趋势与转录组数据不同。我们的研究可能为BSK基因在生长中的进一步功能分析奠定基础。发展,苜蓿耐盐胁迫。
Alfalfa (Medicago L.) is a high-quality perennial leguminous forage with the advantages of salt tolerance, mowing tolerance, high protein content, and other economically valuable characteristics. As the sixth class of plant hormones, brassinosteroids (BRs) play indispensable roles in modulating a variety of plant growth, maturation, and environmental adaptation processes, thereby influencing vegetal expansion and development. Brassinosteroid signal kinases (BSKs) are key cytoplasmic receptor kinases downstream of the BR signaling transduction pathway, participating in plant growth, development, and stress regulation. However, the phylogenetic and expression pattern analyses of the BSK gene family among the five alfalfa species have rarely been reported; in this study, 52 BSK family members were found in the genomes of the five subspecies, and phylogenetic trees were constructed according to protein sequences, allowing us to categorize all BSKs into seven distinct groups. Domain, conserved motif, and exon-intron structural analyses showed that most BSK members were relatively conserved, except for MtBSK3-2, MtBSK7-1, and MtBSK7-2, which may be truncated members. Intra-species collinearity and Ka/Ks analyses showed that purifying selection influenced BSK genes during evolution; most of the cis-acting elements in the promoter region were associated with responses, such as light, defense, and stress, anaerobic induction, MeJA, and abscisic acid. Expression pattern analysis indicated that the majority of alfalfa genes exhibited downregulation after reaching a peak at 0.5 h after treatment with 250 mM NaCl, especially for MsBSK14, MsBSK15, MsBSK17, MsBSK19, and MsBSK21; meanwhile, MsBSK4, MsBSK7, and MsBSK9 increased and were highly expressed at 12 h, demonstrating significantly altered expression patterns under salt stress; furthermore, MsBSK4, MsBSK7, and MsBSK9 exhibited expression specifically in the leaves. qRT-PCR analysis confirmed the expression trends for MsBSK4, MsBSK7, MsBSK9, MsBSK14, MsBSK15, and MsBSK16 matched the transcriptome data. However, the trends for MsBSK17, MsBSK19, and MsBSK21 diverged from the transcriptome data. Our study may provide a foundation for further functional analyses of BSK genes in growth, development, and salt stress tolerance in alfalfa.