Kapadia Chintan, Datta Rahul, Mahammad Saiyed Mufti, Tomar Rukam Singh, Kheni Jasmin Kumar, Ercisli Sezai
Department of Plant Molecular Biology and Biotechnology, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari 396450, India.
Department of Geology and Pedology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska1, 61300 Brno, Czech Republic.
ACS Omega. 2023 Jan 5;8(2):2648-2657. doi: 10.1021/acsomega.2c07097. eCollection 2023 Jan 17.
MicroRNAs (miRNAs), a type of short noncoding RNA molecule (21-23 nucleotides), mediate repressive gene regulation through RNA silencing at the posttranscriptional level and play an important role in the defense response to abiotic and biotic stresses. miRNAs of the plant system have been studied in model crops for their diverse regulatory role while less is known about their significance in other plants whose genome and transcriptome data are scarce in the database, including eggplant ( L.). In the present study, a next-generation sequencing platform was used for the sequencing of miRNA, and real-time quantitative PCR for miRNAs was used to validate the gene expression patterns of miRNAs in plantlets infected with the bacterial wilt-causing pathogen (). Sequence analyses showed the presence of 375 miRNAs belonging to 29 conserved families. The miR414 is highly conserved miRNA across the plant system while miR5658 and miR5021 were found exclusively in surprisingly, these miRNAs were found in eggplants too. The most abundant families were miR5658 and miR414. Ppt-miR414, hvu-miR444b, stu-miR8020, and sly miR5303 were upregulated in Pusa purple long (PPL) (susceptible) at 48 h postinfection, followed by a decline after 96 h postinfection. A similar trend was obtained in ath-miR414, stu-mir5303h, alymiR847-5p, far-miR1134, ath-miR5021, ath-miR5658, osa-miR2873c, lja-miR7530, stu-miR7997c, and gra-miR8741 but at very low levels after infection in the susceptible variety, indicating their negative role in the suppression of host immunity. On the other hand, osa-miR2873c was found to be slightly increased after 96 hpi from 48 hpi. Most of the miRNAs under study showed relatively lower expression in the resistant variety Arka Nidhi after infection than in the susceptible variety. These results shed light on a deeper regulatory role of miRNAs and their targets in regulation of the plant response to bacterial infection. The present experiment and their results suggested that the higher expression of miRNA leads to a decline in host mRNA and thus shows susceptibility.
微小RNA（miRNA）是一类短的非编码RNA分子（21 - 23个核苷酸），通过转录后水平的RNA沉默介导基因抑制调控，在植物对非生物和生物胁迫的防御反应中发挥重要作用。植物系统中的miRNA已在模式作物中进行了研究，以了解其多样的调控作用，而对于数据库中基因组和转录组数据稀缺的其他植物，包括茄子（Solanum melongena L.），其miRNA的重要性了解较少。在本研究中，使用下一代测序平台对miRNA进行测序，并使用miRNA的实时定量PCR来验证感染青枯病致病病原菌（Ralstonia solanacearum）的茄子幼苗中miRNA的基因表达模式。序列分析表明存在属于29个保守家族的375个miRNA。miR414是整个植物系统中高度保守的miRNA，而miR5658和miR5021仅在茄子中发现，令人惊讶的是，这些miRNA在茄子中也存在。最丰富的家族是miR5658和miR414。在感染后48小时，Pusa purple long（PPL，易感品种）中的ppt - miR414、hvu - miR444b、stu - miR8020和sly miR5303上调，随后在感染后96小时下降。在ath - miR414、stu - mir5303h、alymiR847 - 5p、far - miR1134、ath - miR5021、ath - miR5658、osa - miR2873c、lja - miR7530、stu - miR7997c和gra - miR8741中也获得了类似趋势，但在易感品种感染后水平非常低，表明它们在抑制宿主免疫中起负面作用。另一方面，发现osa - miR2873c在感染后96小时相对于48小时略有增加。大多数研究的miRNA在感染后，在抗性品种Arka Nidhi中的表达相对低于易感品种。这些结果揭示了miRNA及其靶标在调节植物对细菌感染反应中的更深层次调控作用。本实验及其结果表明，miRNA的高表达导致宿主mRNA下降，从而表现出易感性。
