Identification of Nitrogen Starvation-Responsive miRNAs to Reveal the miRNA-Mediated Regulatory Network in Betula luminifera

Abstract

Because of the immobility, plants encounter a series of stresses, such as varied nutrient concentrations in soil, which regulate plant growth, development, and phase transitions. Nitrogen (N) is one of the most limiting factors for plants, which was exemplified by the fact that low nitrogen (LN) has a great adverse effect on plant growth and development. In the present study, we explored the potential role of microRNAs (miRNAs) in response to LN stress in Betula luminifera. We identified 198 miRNAs using sRNA sequencing, including 155 known and 43 novel miRNAs. Among them, 98 known miRNAs and 31 novel miRNAs were differentially expressed after 0.5 h or 24 h of LN stress. Based on degradome data, 122 differential expressed miRNAs (DEmiRNAs) including 102 known miRNAs and 20 novel miRNAs targeted 203 genes, comprising 321 miRNA–target pairs. A big proportion of target genes were transcription factors and functional proteins, and most of the Gene Ontology terms were enriched in biological processes; moreover, one Kyoto Encyclopedia of Genes and Genomes term “ascorbate and aldarate metabolism” was significantly enriched. The expression patterns of six miRNAs and their corresponding target genes under LN stress were monitored. According to the potential function for targets of DEmiRNAs, a proposed regulatory network mediated by miRNA–target pairs under LN stress in B. luminifera was constructed. Taken together, these findings provide useful information to elucidate miRNA functions and establish a framework for exploring N signaling networks mediated by miRNAs in B. luminifera. It may provide new insights into the genetic engineering of the high use efficiency of N in forestry trees.

Nitrogen starvation response in hornworts and liverworts provides little evidence for complex priming to the cyanobiont

“…Intriguingly, we found many more TF genes to be upregulated under nitrogen starvation in the hornwort than in the liverwort. Some of them are well-known to show similar responses in flowering plants including, HD-ZIP III (Lin et al, 2022), WRKY (Wang et al, 2019), MYB (Zhang et al, 2012; Wang et al, 2019, 2020b), C2H2 (SUN et al, 2012; Chen et al, 2017), C2C2-Dof (Yanagisawa et al, 2004; Curci et al, 2017), GARP (Medici et al, 2015) and RWP_RK (Chardin et al, 2014; Wu et al, 2020) TFs. It is unclear why these TFs are not responsive in the liverwort B. pusilla although these genes are mostly present in the genome of liverwort B. pusilla.…”

Genome-wide identification of nitrate-responsive microRNAs by small RNA sequencing in the rice restorer cultivar Nanhui 511

“…Furthermore, several miRNAs have been identified and characterized in plants, including miR167 and miR174 involved in signaling during root development (Meng et al, 2011;Liang et al, 2015). More importantly,miR156,miR159,miR160,miR166,miR169,miR171,miR172,miR319,miR396,miR397,miR398,miR399, and miR408, which are involved in plant growth and development, have been shown to regulate N absorption and assimilation (Xu et al, 2011;Liang et al, 2012;Nguyen et al, 2015;Tiwari et al, 2020;Lin et al, 2022;Lu et al, 2022). Previous studies have summarized the miRNAs involved in plant sensory functions, nutrient uptake, long-distance root transport, and physiological functions related to nutrients (Chiou, 2007;Islam et al, 2022b).…”