Identification of Regulatory Networks of MicroRNAs and Their Targets in Response to Colletotrichum gloeosporioides in Tea Plant (Camellia sinensis L.)

Abstract

Anthracnose disease is caused by Colletotrichum gloeosporioides, and is common in leaves of the tea plant (Camellia sinensis). MicroRNAs (miRNAs) have been known as key modulators of gene expression in response to environmental stresses, disease resistance, defense responses, and plant immunity. However, the role of miRNAs in responses to C. gloeosporioides remains unexplored in tea plant. Therefore, in the present study, six miRNA sequencing data sets and two degradome data sets were generated from C. gloeosporioides-inoculated and control tea leaves. A total of 485 conserved and 761 novel miRNAs were identified. Of those, 239 known and 369 novel miRNAs exhibited significantly differential expression under C. gloeosporioides stress. One thousand one hundred thirty-four and 596 mRNAs were identified as targets of 389 conserved and 299 novel miRNAs by degradome analysis, respectively. Based on degradome analysis, most of the predicted targets are negatively correlated with their corresponding conserved and novel miRNAs. The expression levels of 12 miRNAs and their targets were validated by quantitative real-time PCR. A negative correlation between expression profiles of five miRNAs (PC-5p-80764_22, csn-miR160c, csn-miR828a, csn-miR164a, and csn-miR169e) and their targets (WRKY, ARF, MYB75, NAC, and NFY transcription factor) was observed. The predicted targets of five interesting miRNAs were further validated through 5’RLM-RACE. Furthermore, Gene Ontology and metabolism pathway analysis revealed that most of the target genes were involved in the regulation of auxin pathway, ROS scavenging pathway, salicylic acid mediated pathway, receptor kinases, and transcription factors for plant growth and development as well as stress responses in tea plant against C. gloeosporioides stress. This study enriches the resources of stress-responsive miRNAs and their targets in C. sinensis and thus provides novel insights into the miRNA-mediated regulatory mechanisms, which could contribute to the enhanced susceptibility of C. gloeosporioides in tea plant.

Brassinosteroid Priming Improves Peanut Drought Tolerance via Eliminating Inhibition on Genes in Photosynthesis and Hormone Signaling

“…Many known additional regulations in other plants could be also involved in the BR priming, including small RNA regulation [ 43 , 63 , 64 , 65 , 66 ], lncRNA regulation [ 67 ], alternative splicing in transcripts [ 65 , 68 ], and methylation regulation [ 69 ]. These additional regulations may work in a network manner under drought stress after BR-priming and are worth of dissecting in future using omics methods [ 70 , 71 ].…”

Tea plant genomics: achievements, challenges and perspectives

“…For instance, Cs-miR156 regulates catechin accumulation in tea plants by suppressing the expression of the target gene SPL in the presence of different nitrogen forms 128 . The characterization of tea plant miRNA regulatory networks in response to Colletotrichum gloeosporioides , which is considered one of the dominant endophytic taxa in tea plants, indicated that miRNAs may be involved in the response to C. gloeosporioides attack 134 . miRNA characterization in tea plants under cold and drought stresses suggested the potential existence of an miRNA-mediated regulatory mechanism under abiotic stresses showing coherent or incoherent relationships with target genes to prevent tea plants from being injured 129–132 .…”

Transcriptome and Phytochemical Analyses Provide New Insights Into Long Non-Coding RNAs Modulating Characteristic Secondary Metabolites of Oolong Tea (Camellia sinensis) in Solar-Withering

“…To verify the miRNA cleavage sites, a modified 5′ RNA ligasemediated rapid amplification of cDNA ends (RACE) (5′ RLM-RACE) experiment was performed with the First-Choice RLM-RACE Kit (Thermo Fisher Scientific, Carlsbad, CA, USA) as previously described (Jeyaraj et al, 2019). The primers used to verify the cleavage sites are listed in Supplementary Table S1.…”