Boron-deficiency-responsive microRNAs and their targets in Citrus sinensis leaves

ABSTRACT: Background: MicroRNAs play important roles in the adaptive responses of plants to nutrient deficiencies. Here, we sequenced two small RNA libraries from B-deficient and -sufficient (control) Citrus sinensis leaves, respectively, using Illumina sequencing in order to identify the potential miRNAs related to the tolerance of citrus to B-deficiency. Results: Ninety one (83 known and 8 novel) up- and 81 (75 known and 6 novel) downregulated miRNAs were isolated from B-deficient leaves. The great alteration of miRNA expression might contribute to the tolerance of citrus to B-deficiency. The adaptive responses of miRNAs to B-deficiency might related to several aspects: (a) attenuation of plant growth and development by repressing auxin signaling due to decreased TIR1 level and ARF-mediated gene expression by altering the expression of miR393, miR160 and miR3946; (b) maintaining leaf phenotype and enhancing the stress tolerance by up-regulating NACs targeted by miR159, miR782, miR3946 and miR7539; (c) activation of the stress responses and antioxidant system through down-regulating the expression of miR164, miR6260, miR5929, miR6214, miR3946 and miR3446; (d) decreasing the expression of major facilitator superfamily protein genes targeted by miR5037, thus lowering B export from plants. Also, B-deficiency-induced downregulation of miR408 might play a role in plant tolerance to B-deficiency by regulating Cu homeostasis and enhancing superoxide dismutase activity. Conclusions: Our study reveals some novel responses of citrus to B-deficiency, which increase our understanding of the adaptive mechanisms of citrus to B-deficiency at the miRNA (post-transcriptional) level.

ORGANISM(S): Citrus sinensis

PROVIDER: GSE72108 | GEO | 2017/02/10

SECONDARY ACCESSION(S): PRJNA292994

REPOSITORIES: GEO