Transcriptional Regulation of zma-MIR528a by Action of Nitrate and Auxin in Maize

Abstract

In recent years, miR528, a monocot-specific miRNA, has been assigned multifaceted roles during development and stress response in several plant species. However, the transcription regulation and the molecular mechanisms controlling MIR528 expression in maize are still poorly explored. Here we analyzed the zma-MIR528a promoter region and found conserved transcription factor binding sites related to diverse signaling pathways, including the nitrate (TGA1/4) and auxin (AuxRE) response networks. Accumulation of both pre-miR528a and mature miR528 was up-regulated by exogenous nitrate and auxin treatments during imbibition, germination, and maize seedling establishment. Functional promoter analyses demonstrated that TGA1/4 and AuxRE sites are required for transcriptional induction by both stimuli. Overall, our findings of the nitrogen- and auxin-induced zma-MIR528a expression through cis-regulatory elements in its promoter contribute to the knowledge of miR528 regulome.

Unveiling the Regulatory Role of miRNAs in Internode Elongation: Integrated Analysis of MicroRNA and mRNA Expression Profiles across Diverse Dwarfing Treatments in Maize (Zea mays L.)

“…Auxin treatment has been observed to induce miR528 accumulation. 46 The br2 mutation's influence on local auxin accumulation in the internode elongation zone is linked to an upsurge in miR528a expression (Figure 6D). ZmmiR528a-5p's expression exhibits a strong correlation with auxin levels in this zone (Figure 3F; Figure 6D).…”

“…Auxin treatment has been observed to induce miR528 accumulation . The br2 mutation’s influence on local auxin accumulation in the internode elongation zone is linked to an upsurge in miR528a expression (Figure D).…”

The Grapevine Transcription Factor VvTGA8 Enhances Resistance to White Rot via the Salicylic Acid Signaling Pathway in Tomato

“…In S. lycopersicum, the expression of the SA signaling pathway marker gene PR1 was reduced in TGA1.a-silenced lines, which increased susceptibility to P. syringae [43]. In addition, TGA1 and its homologues have been studied in maize, grapevine, peach, and other taxa [8,44,45]. However, whether VvNPR1 is necessary for VvTGA8-mediated resistance and the mechanism by which VvTGA8 specifically regulates PR expression in grapevine still need further exploration.…”

The Fascinating World of Plant Non-Coding RNAs

“…Luján-Soto et al investigated the regulation of zma-MIR528a, a microRNA involved in nitrogen and auxin responses in plants. Their findings provide insights into the regulatory elements controlling the expression of this miRNA and contribute to the overall understanding of the miR528 regulome [ 4 ]. A common practice to understand the functional role of miRNAs is to combine different sequencing techniques and explore miRNA-mRNA regulatory networks.…”