Identification and analysis of brown planthopper-responsive microRNAs in resistant and susceptible rice plants

Abstract

The brown planthopper (BPH) is the most devastating insect pest of rice. The rice gene BPH15 confers resistance to BPH. MicroRNAs (miRNAs) regulate a spectrum of development and defense response processes in plants. In this study, we analyzed six miRNA profiles of a BPH15 introgression line (P15) and a susceptible recipient line (PC) at three time points (0 h, 6 h and 48 h) after BPH attack, and identified 464 known miRNAs and 183 potential novel miRNAs. Before the BPH feeding, we identified 23 miRNAs differentially expressed in P15 and PC. We speculated that the resistant plant is in a priming state by the regulation of miRNAs. After the BPH feeding, 104 miRNAs were found to be expressed differentially in P15 (68 in P15-6/P15-0, 36 in P15-48/P15-0), and 80 miRNAs were found expressed differentially in PC (32 in PC-6/PC-0, 48 in PC-48/PC-0), which illustrated that miRNA expression is activated upon attack. These miRNAs regulate different pathways that contribute to the basal defense and specific resistance of rice to the BPH. Our study provides additional data for scientists to further explore the mechanism of plant defense against insect attack and to find a way for efficient insect control.

A combined microRNA and transcriptome analyses illuminates the resistance response of rice against brown planthopper

“…Seventeen of the miR-NAs, miR160c-3p/e-3p, miR166a-5p/e-5p/h-5p, miR169h/i-5p.1/i-5p.2/j/k/l, miR1859, miR1861b/j/l, miR390-3p and miR396c-3p, were present in both groups, suggesting their involvement in the defense response of rice against BPH are consistent with their respective roles in pathogen defense [24][25][26]. Previously, the BPH-responsive miRNAs were identified in a BPH15 introgression line [29]. In both the BPH15 introgression and the BPH6G lines, some miRNA exhibited similar expression trends, such as miR156b-3p, miR169h/i-3p/i-5p.1/i-5p.2/j/k/l/m/o, miR396c-5p, miR399j, miR530-5p and miR5513, suggesting a conserved and diverse resistance mechanisms against BPH mediated by BPH6 and BPH15.…”

“…2a), many of which belonged to known miRNA families including miR156, miRNA160, miR166, miR169, miR1846, miR1861 and miR319 (Additional file 3: Table S2). Members of the miRNA families were reported to be involved not only in growth, development, grain size and hormone signaling, but also in response to biotic and abiotic stress [21][22][23][24][25][26][27][28][29][30][31]. These BPH6 responsive DEMs might be involved in response to BPH.…”

“…The endpoint method was used to collect samples through BPH treatment [29]. Although all processes began at different time, they were stopped at the same specified time.…”

“…However, few miRNAs have been revealed functioning in insect response. BPH-responsive miRNAs were investigated from resistant rice in comparison with susceptible plants [29]. miR156 and miR396 negatively regulated BPH resistance through regulating Jasmonic acid (JA) and flavonoid biosynthetic pathways, respectively [30,31].…”

The OsmiR396–OsGRF8–OsF3H‐flavonoid pathway mediates resistance to the brown planthopper in rice (Oryza sativa)

“…This corroborates the work of Wu et al . (Wu et al ., 2017b), which showed that many miRNAs responded differentially to BPH in resistant and susceptible rice plants, indicating that miRNAs might mediate different pathways involved in the basal defence and specific resistance to BPH. We further revealed a detailed molecular mechanism mediated by one of the responsive miRNAs, OsmiR396, which was induced by BPH infestation (Figure a,b).…”