Dutta Madhushree, Raturi Vidhi, Gahlaut Vijay, Kumar Akhil, Sharma Paras, Verma Vipasha, Gupta Vijai Kishor, Sood Salej, Zinta Gaurav
Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India.
Front Plant Sci. 2022 Aug 16;13:933740. doi: 10.3389/fpls.2022.933740. eCollection 2022.
Potato is a temperate crop consumed globally as a staple food. High temperature negatively impacts the tuberization process, eventually affecting crop yield. DNA methylation plays an important role in various developmental and physiological processes in plants. It is a conserved epigenetic mark determined by the dynamic concurrent action of cytosine-5 DNA methyltransferases () and demethylases (). However, and remain unidentified in potato, and their expression patterns are unknown under high temperatures. Here, we performed genome-wide analysis and identified 10 C5-MTases and 8 DeMets in potatoes. Analysis of their conserved motifs, gene structures, and phylogenetic analysis grouped into four subfamilies (, and ) and into three subfamilies (, and ). Promoter analysis showed the presence of multiple cis-regulatory elements involved in plant development, hormone, and stress response. Furthermore, expression dynamics of and were determined in the different tissues (leaf, flower, and stolon) of heat-sensitive (HS) and heat-tolerant (HT) genotypes under high temperature. qPCR results revealed that high temperature resulted in pronounced upregulation of and genes in the HT genotype. Likewise, demethylases showed strong upregulation in HT genotype as compared to HS genotype. Several positive ( and ) and negative (, and ) regulators are involved in the potato tuberization. Expression analysis of these genes revealed that high temperature induces the expression of positive regulators in the leaf and stolon samples of HT genotype, possibly through active DNA demethylation and RNA-directed DNA methylation (RdDM) pathway components. Our findings lay a framework for understanding how epigenetic pathways synergistically or antagonistically regulate the tuberization process under high-temperature stress in potatoes. Uncovering such mechanisms will contribute to potato breeding for developing thermotolerant potato varieties.
马铃薯是一种温带作物，作为主食在全球范围内被食用。高温对块茎形成过程产生负面影响，最终影响作物产量。DNA甲基化在植物的各种发育和生理过程中发挥着重要作用。它是一种保守的表观遗传标记，由胞嘧啶-5 DNA甲基转移酶（）和去甲基化酶（）的动态协同作用决定。然而，马铃薯中的 和 仍未被鉴定出来，它们在高温下的表达模式也未知。在这里，我们进行了全基因组分析，在马铃薯中鉴定出10种C5-甲基转移酶和8种去甲基化酶。对它们的保守基序、基因结构进行分析，并通过系统发育分析将 分为四个亚家族（、 和 ），将 分为三个亚家族（、 和 ）。启动子分析表明存在多个参与植物发育、激素和应激反应的顺式调控元件。此外，还测定了高温下热敏（HS）和耐热（HT）基因型不同组织（叶、花和匍匐茎）中 和 的表达动态。qPCR结果显示，高温导致HT基因型中 和 基因显著上调。同样，与HS基因型相比，去甲基化酶在HT基因型中表现出强烈上调。几个正向（ 和 ）和负向（、 和 ）调控因子参与马铃薯块茎形成。这些基因的表达分析表明，高温可能通过活性DNA去甲基化和RNA指导的DNA甲基化（RdDM）途径成分诱导HT基因型叶和匍匐茎样本中正向调控因子的表达。我们的研究结果为理解表观遗传途径如何在马铃薯高温胁迫下协同或拮抗调控块茎形成过程奠定了框架。揭示这些机制将有助于马铃薯育种，以培育耐热马铃薯品种。
