Gong Luping, Li Bingbing, Zhu Tao, Xue Baoping
College of Life Science and Engineering, Henan University of Urban Construction, Pingdingshan, China.
State Key Laboratory of Hybrid Rice, Department of Plant Sciences, College of Life Sciences, Wuhan University, Wuhan, China.
Front Plant Sci. 2023 Sep 20;14:1243806. doi: 10.3389/fpls.2023.1243806. eCollection 2023.
Dirigent (DIR) proteins play essential roles in regulating plant growth and development, as well as enhancing resistance to abiotic and biotic stresses. However, the whole-genome identification and expression profiling analysis of gene family in millet have not been systematically understood. In this study, we conducted genome-wide identification and expression analysis of the gene family, including gene structures, conserved domains, evolutionary relationship, chromosomal locations, -elements, duplication events, gene collinearity and expression patterns. A total of 38 members distributed on nine chromosomes were screened and identified. SiDIR family members in the same group showed higher sequence similarity. The phylogenetic tree divided the proteins into six subfamilies: DIR-a, DIR-b/d, DIR-c, DIR-e, DIR-f, and DIR-g. According to the tertiary structure prediction, DIR proteins (like SiDIR7/8/9) themselves may form a trimer to exert function. The result of the syntenic analysis showed that tandem duplication may play the major driving force during the evolution of . RNA-seq data displayed higher expression of 16 genes in root tissues, and this implied their potential functions during root development. The results of quantitative real-time PCR (RT-qPCR) assays revealed that SiDIR genes could respond to the stress of CaCl, CdCl, NaCl, and PEG6000. This research shed light on the functions of SiDIRs in responding to abiotic stress and demonstrated their modulational potential during root development. In addition, the membrane localization of SiDIR7/19/22 was confirmed to be consistent with the forecast. The results above will provide a foundation for further and deeper investigation of DIRs.
定向蛋白（DIR）在调节植物生长发育以及增强对非生物和生物胁迫的抗性方面发挥着重要作用。然而，谷子中该基因家族的全基因组鉴定和表达谱分析尚未得到系统的了解。在本研究中，我们对该基因家族进行了全基因组鉴定和表达分析，包括基因结构、保守结构域、进化关系、染色体定位、顺式作用元件、重复事件、基因共线性和表达模式。共筛选并鉴定出分布在9条染色体上的38个成员。同一组中的SiDIR家族成员显示出较高的序列相似性。系统发育树将这些蛋白分为六个亚家族：DIR-a、DIR-b/d、DIR-c、DIR-e、DIR-f和DIR-g。根据三级结构预测，DIR蛋白（如SiDIR7/8/9）自身可能形成三聚体来发挥功能。共线性分析结果表明，串联重复可能是其进化过程中的主要驱动力。RNA-seq数据显示16个基因在根组织中表达较高，这暗示了它们在根发育过程中的潜在功能。定量实时PCR（RT-qPCR）分析结果表明，SiDIR基因能够响应CaCl、CdCl、NaCl和PEG6000的胁迫。本研究揭示了SiDIRs在应对非生物胁迫中的功能，并证明了它们在根发育过程中的调节潜力。此外，SiDIR7/19/22的膜定位经证实与预测一致。上述结果将为进一步深入研究DIRs提供基础。
