Abstract
BackgroundSoybean is a major legume crop with high nutritional and environmental values suitable for sustainable agriculture. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), are important regulators of gene functions in eukaryotes. However, the interactions between these two types of ncRNAs in the context of plant physiology, especially in response to salinity stress, are poorly understood.ResultsHere, we challenged a cultivated soybean accession (C08) and a wild one (W05) with salt treatment and obtained their small RNA transcriptomes at six time points from both root and leaf tissues. In addition to thoroughly analyzing the differentially expressed miRNAs, we also documented the first case of miRNA arm-switching (miR166m), the swapping of dominant miRNA arm expression, in soybean in different tissues. Two arms of miR166m target different genes related to salinity stress (chloroplastic beta-amylase 1 targeted by miR166m-5p and calcium-dependent protein kinase 1 targeted by miR166m-3p), suggesting arm-switching of miR166m play roles in soybean in response to salinity stress. Furthermore, two pairs of miRNA:lncRNA interacting partners (miR166i-5p and lncRNA Gmax_MSTRG.35921.1; and miR394a-3p and lncRNA Gmax_MSTRG.18616.1) were also discovered in reaction to salinity stress.ConclusionsThis study demonstrates how ncRNA involves in salinity stress responses in soybean by miRNA arm switching and miRNA:lncRNA interactions. The behaviors of ncRNAs revealed in this study will shed new light on molecular regulatory mechanisms of stress responses in plants, and hence provide potential new strategies for crop improvement.
Highlights
Soybean is a major legume crop with high nutritional and environmental values suitable for sustain‐ able agriculture
Differential miRNA expression in soybean under salinity stress The setting of the experiment is described in materials and methods and a total of 72 small RNA datasets were generated for analysis (Fig. 2)
By comparing samples across different treatments, 35 upregulation and 77 downregulation events were found in the leaf and root between the different time points (Fig. 3)
Summary
Soybean is a major legume crop with high nutritional and environmental values suitable for sustain‐ able agriculture. Besides protein-coding genes, noncoding RNAs (ncRNAs) are important regulators of gene expressions in plants, ranging from moderating development to coping with abiotic and biotic stresses. Many other miRNAs were found to be associated with the development of soybean seeds [6,7,8], roots [9], and flowers [10]. In addition to the developmental roles, miRNAs are associated with the responses toward abiotic stresses in soybean [3, 13,14,15,16,17], such as the involvements of gma-miR169c and gma-miR394a in drought tolerance and salt sensitivity [18,19,20], and miR399a and miR172c in root development under salinity stress [21, 22]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
