Duarte Karoline Estefani, Basso Marcos Fernando, de Oliveira Nelson Geraldo, da Silva José Cleydson Ferreira, de Oliveira Garcia Bruno, Cunha Bárbara Andrade Dias Brito, Cardoso Thiago Bergamo, Nepomuceno Alexandre Lima, Kobayashi Adilson Kenji, Santiago Thaís Ribeiro, de Souza Wagner Rodrigo, Molinari Hugo Bruno Correa
Embrapa Agroenergy, Brasília, DF 70297-400 Brazil.
Federal University of ABC, Santo André, SP 09210-580 Brazil.
Physiol Mol Biol Plants. 2022 Aug;28(8):1607-1624. doi: 10.1007/s12298-022-01226-z. Epub 2022 Sep 28.
Water deficit is a major constraint for crops of economic importance in almost all agricultural regions. However, plants have an active defense system to adapt to these adverse conditions, acting in the reprogramming of gene expression responsible for encoding microRNAs (miRNAs). These miRNAs promote the regulation to the target gene expression by the post-transcriptional (PTGS) and transcriptional gene silencing (TGS), modulating several pathways including defense response to water deficit. The broader knowledge of the miRNA expression profile and its regulatory networks in response to water deficit can provide evidence for the development of new biotechnological tools for genetic improvement of several important crops. In this study, we used accession A10.1 as a C4 model plant to widely investigate the miRNA expression profile in early responses to different levels of water deficit. Ecophysiological studies in under water deficit and after rewatering demonstrated a drought tolerant accession, capable of a rapid recovery from the stress. Deep small RNA sequencing and degradome studies were performed in plants submitted to drought to identify differentially expressed miRNA genes and their predicted targets, using in silico analysis. Our findings showed that several miRNAs were differentially modulated in response to distinctive levels of water deficit and after rewatering. The predicted mRNA targets mainly corresponded to genes related to cell wall remodeling, antioxidant system and drought-related transcription factors, indicating that these genes are rapidly regulated in early responses to drought stress. The implications of these modulations are extensively discussed, and higher-effect miRNAs are suggested as major players for potential use in genetic engineering to improve drought tolerance in economically important crops, such as sugarcane, maize, and sorghum.
The online version contains supplementary material available at 10.1007/s12298-022-01226-z.
水分亏缺是几乎所有农业地区具有经济重要性的作物面临的主要限制因素。然而,植物具有活跃的防御系统来适应这些不利条件,这一系统作用于负责编码微小RNA(miRNA)的基因表达重编程。这些miRNA通过转录后基因沉默(PTGS)和转录基因沉默(TGS)促进对靶基因表达的调控,调节包括对水分亏缺的防御反应在内的多种途径。对miRNA表达谱及其响应水分亏缺的调控网络有更广泛的了解,可为开发用于几种重要作物遗传改良的新生物技术工具提供依据。在本研究中,我们使用A10.1种质作为C4模式植物,广泛研究了其对不同程度水分亏缺早期反应中的miRNA表达谱。对水分亏缺及复水后的生态生理学研究表明,该种质耐旱,能够从胁迫中快速恢复。对遭受干旱的植物进行了深度小RNA测序和降解组研究,以通过计算机分析鉴定差异表达的miRNA基因及其预测靶标。我们的研究结果表明,几种miRNA在响应不同程度的水分亏缺及复水后受到差异调节。预测的mRNA靶标主要对应于与细胞壁重塑、抗氧化系统和干旱相关转录因子相关的基因,表明这些基因在对干旱胁迫的早期反应中受到快速调控。对这些调节的影响进行了广泛讨论,并提出高效miRNA作为主要参与者,有可能用于基因工程,以提高甘蔗、玉米和高粱等高经济价值作物的耐旱性。
在线版本包含可在10.1007/s12298-022-01226-z获取的补充材料。