Gamas Nawress, Smaoui Fahmi, Ben Romdhane Walid, Wiszniewska Alina, Baazaoui Narjes, Bouteraa Mohamed Taieb, Chouaibi Yosra, Ben Hsouna Anis, Kačániová Miroslava, Kluz Maciej Ireneusz, Garzoli Stefania, Ben Saad Rania
Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P "1177", Sfax 3018, Tunisia.
Faculty of Sciences of Gafsa, University of Gafsa, Sidi Ahmed Zarrouk, Gafsa 2112, Tunisia.
Biology (Basel). 2025 Apr 11;14(4):404. doi: 10.3390/biology14040404.
Plant defensins (PDFs) are a group of cationic antimicrobial peptides that are distinguished by their unique tertiary structure and play significant roles in physiological metabolism, growth, and stress tolerance. Defensins are key components of plant innate immunity; they can target a wide variety of microorganisms. This study aimed to identify and investigate the role of PDFs () in response to environmental stresses. Prior to this, in silico analyses of genes were conducted to assess their chromosomal locations, conserved motifs, exon-intron distribution, and cis-regulatory elements in the promoter regions. Additionally, bioinformatic analyses were performed to characterize the structure of TdPDF proteins, evaluate their phylogenetic relationships, predict their subcellular localization, and estimate their physicochemical properties. Docking studies were conducted to assess the interactions between TdPDF proteins and the fungal plasma membrane. A total of 28 genes were identified in durum wheat based on their conserved domain PF00304 (gamma-thionin). These genes are distributed across all chromosomes of the durum wheat genome, except for chromosomes 4A and 7A. Analysis of the promoters of these genes revealed numerous elements associated with development, hormone responsiveness, and environmental stress. The majority of TdPDF proteins were predicted to be located extracellular. In addition, TdPDF proteins were classified into three clusters based on sequence similarity. Phylogenetic analysis suggested that TdPDF proteins share ancestral similarities with the PDF sequences of other monocotyledonous species. Molecular docking studies revealed that TdPDF proteins interact with fungal plasma membranes, suggesting that they play a critical role in the resistance of plants to pathogen infections. Expression analysis underlined the crucial role of nine genes in the defense responses of durum wheat against both pathogenic and environmental stressors. Overall, our findings underscore the potential of genes in host-plant resistance and highlight opportunities for their application in crop improvement toward stress tolerance.
植物防御素（PDFs）是一类阳离子抗菌肽，以其独特的三级结构为特征，在生理代谢、生长和胁迫耐受性方面发挥着重要作用。防御素是植物先天免疫的关键组成部分；它们可以靶向多种微生物。本研究旨在鉴定和研究PDFs（）在应对环境胁迫中的作用。在此之前，对基因进行了电子分析，以评估它们的染色体位置、保守基序、外显子 - 内含子分布以及启动子区域中的顺式调控元件。此外，还进行了生物信息学分析，以表征TdPDF蛋白的结构、评估它们的系统发育关系、预测它们的亚细胞定位并估计它们的理化性质。进行对接研究以评估TdPDF蛋白与真菌质膜之间的相互作用。基于其保守结构域PF00304（γ - 硫堇），在硬粒小麦中总共鉴定出28个基因。这些基因分布在硬粒小麦基因组的所有染色体上，但4A和7A染色体除外。对这些基因启动子的分析揭示了许多与发育、激素反应性和环境胁迫相关的元件。大多数TdPDF蛋白预计位于细胞外。此外，TdPDF蛋白根据序列相似性被分为三个簇。系统发育分析表明，TdPDF蛋白与其他单子叶植物物种的PDF序列具有祖先相似性。分子对接研究表明，TdPDF蛋白与真菌质膜相互作用，表明它们在植物对病原体感染的抗性中起关键作用。表达分析强调了九个基因在硬粒小麦对致病和环境胁迫因子的防御反应中的关键作用。总体而言，我们的研究结果强调了基因在宿主植物抗性中的潜力，并突出了它们在作物改良以提高胁迫耐受性方面的应用机会。
