Dubey Himanshu, Kiran Kanti, Jaswal Rajdeep, Jain Priyanka, Kayastha Arvind M, Bhardwaj Subhash C, Mondal Tapan Kumar, Sharma Tilak Raj
ICAR-National Research Centre on Plant Biotechnology, Pusa Campus, New Delhi, 110012, India.
School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.
Funct Integr Genomics. 2019 May;19(3):391-407. doi: 10.1007/s10142-018-00652-1. Epub 2019 Jan 7.
Cross-kingdom RNAi is a well-documented phenomenon where sRNAs generated by host and pathogens may govern resistance or susceptible phenotypes during host-pathogen interaction. With the first example of the direct involvement of fungal generated sRNAs in virulence of plant pathogenic fungi Botrytis cinerea and recently from Puccinia striiformis f. sp. tritici, we attempted to identify sRNAs in Puccinia triticina (P. triticina). Four sRNA libraries were prepared and sequenced using Illumina sequencing technology and a total of ~ 1-1.28 million potential sRNAs and two microRNA-like small RNA (mil-RNAs) candidates were identified. Computational prediction of targets using a common set of sRNAs and P. triticina mil-RNAs (pt-mil-RNAs) within P. triticina and wheat revealed the majority of the targets as repetitive elements in P. triticina whereas in wheat, the target genes were identified to be involved in many biological processes including defense-related pathways. We found 9 receptor-like kinases (RLKs) and 14 target genes of each related to reactive oxygen species (ROS) pathway and transcription factors respectively, including significant numbers of target genes from various other categories. Expression analysis of twenty selected sRNAs, targeting host genes pertaining to ROS related, disease resistance, metabolic processes, transporter, apoptotic inhibitor, and transcription factors along with two pt-mil-RNAs by qRT-PCR showed distinct patterns of expression of the sRNAs in urediniospore-specific libraries. In this study, for the first time, we report identification of novel sRNAs identified in P. triticina including two pt-mil-RNAs that may play an important role in biotrophic growth and pathogenicity.
跨界RNA干扰是一种有充分文献记载的现象，宿主和病原体产生的小RNA（sRNA）可能在宿主-病原体相互作用过程中决定抗性或敏感表型。随着真菌产生的sRNA直接参与植物病原真菌灰葡萄孢菌致病性的首个实例以及最近条锈菌的相关报道，我们试图鉴定小麦条锈菌中的sRNA。使用Illumina测序技术制备并测序了四个sRNA文库，共鉴定出约100万至128万个潜在sRNA和两个类似微小RNA的小RNA（mil-RNA）候选物。利用小麦条锈菌和小麦中一组常见的sRNA以及小麦条锈菌mil-RNA（pt-mil-RNA）对靶标进行计算预测，结果显示小麦条锈菌中的大多数靶标为重复元件，而在小麦中，靶标基因参与许多生物学过程，包括与防御相关的途径。我们分别发现了9个类受体激酶（RLK）和14个与活性氧（ROS）途径和转录因子相关的靶标基因，包括来自其他各类别的大量靶标基因。通过qRT-PCR对20个选定的靶向与ROS相关、抗病性、代谢过程、转运体、凋亡抑制剂和转录因子的宿主基因的sRNA以及两个pt-mil-RNA进行表达分析，结果显示这些sRNA在夏孢子特异性文库中的表达模式不同。在本研究中，我们首次报道了在小麦条锈菌中鉴定出的新型sRNA，包括两个可能在活体营养生长和致病性中发挥重要作用的pt-mil-RNA。
