MiR1918 enhances tomato sensitivity to Phytophthora infestans infection

Abstract

Late blight of tomato is caused by the oomycete pathogen Phytophthora infestans. In our previous work, we identified and characterized a miR1918 in P. infestans (pi-miR1918), and showed that its sequence is similar to the sequence of tomato miR1918 (sly-miR1918). In this study, we used Arabidopsis thaliana pre-miR159a as a backbone to synthesize pi-miR1918 via PCR and mutagenesis. The artificial pi-miR1918 was used to investigate the role of miR1918 in tomato-P. infestans interaction. Trangenic tomato plants that overexpressed the artificial pi-miR1918 displayed more serious disease symptoms than wild-type tomato plants after infection with P. infestans, as shown by increased number of necrotic cells, lesion sizes and number of sporangia per leaf. The target genes of pi-miR1918 and sly-miR1918 were also predicted for tomato and P. infestans, respectively. qPCR analysis of these targets also performed during tomato-P. infestans interaction. The expression of target gene, RING finger were negatively correlated with miR1918 in the all Lines of transgenic tomato plants. In addition, we used the 5′ RACE to determine the cleavage site of miR1918 to RING finger. These results suggested that miR1918 might be involved in the silencing of target genes, thereby enhancing the susceptibility of tomato to P. infestans infection.

Evaluation of small ncRNAs as a possible epigenetic mechanism mediating the transition from biotrophy to necrotrophy in the life cycle of Phytophthora infestans

“…Moreover, Cui and collaborators (2014) evaluated the expression of four micro RNAs using a qRT-PCR-based approach. The first of these studies was able to prove that the miRNA seemed to have a negative effect on the expression of the associated gene [13], and the second was able to corroborate that the miRNA expression levels were as predicted by the bioinformatics analyses [14].…”

“…Moreover, Jia and collaborators (2017) found that the genes with which P. parasitica small ncRNAs overlap are 40% RXLR effector genes, 50% CRN effector genes and some elicitor genes, all well known for their involvement in host-pathogen interactions. These relationships have also been noted for specific types of small ncRNAs such as micro RNAs and transfer RNAs derived small ncRNAs [12,13,14].…”

Identification of Appropriate Reference Genes for Normalizing miRNA Expression in Citrus Infected by Xanthomonas citri subsp. citri

“…A large body of evidence has shown that miRNA-mediated posttranscriptional regulation plays a fundamental role in plant responses to stressful factors, including pathogen infection, salt, drought, heat, cold, nutrient deficiency and metal toxicity [81][82][83][84][85][86]. A great deal of effort has been focused on the identification and functional analysis of plant miRNAs in response to the infection of pathogens, such as viruses [87][88][89], bacteria [16,[90][91][92] and fungi [13,93,94], which have provided valuable information as to the role miRNAs play in plant-pathogen interactions [95,96].…”

Solanum lycopersicum microRNA1916 targets multiple target genes and negatively regulates the immune response in tomato

“…The leaves were harvested at 0, 6, 12, 24, 48, 72, and 96 hr after infection, and the expression levels of miR1916 and target genes were analysed. Necrotic lesion area was measured using the software ImageJ (Luan, Cui, Wang, & Meng, ; Weiberg et al, ).…”

“…Necrotic lesion area was measured using the software ImageJ (Luan, Cui, Wang, & Meng, 2016;Weiberg et al, 2013). TaKaRa, Dalian, China).…”