Nitrogen (N) is one of the most important macronutrients essential for plant growth and development. Recent studies have revealed that plant small RNAs play a pivotal role in regulating gene expression at post-transcription levels. To date, however, there have been few studies on miRNA(s) involved in the N-deficiency response.

Prof. Yu Diqiu and his research team of Xishuangbanna Tropical Botanical Garden (XTBG) conducted a study to analyze the expression profiles of small RNAs in response to N deficiency and to identify novel miRNAs (miRNAs), a class of non-coding small RNAs, specifically induced by N deprivation. To investigate the response of miRNAs to N deficiency, two small RNA libraries were constructed from N-sufficient (+N) and N-deficient (−N) seedlings by Solexa high-throughput sequencing technology. Arabidopsis (A. thaliana ecotype Columbia) wild-type plants were used to construct small RNAs libraries.

Their data provided insight into the authenticity of previously reported Arabidopsis miRNAs and identify some new miRNAs associated with N-starvation stress responses. It suggested that members from the same miRNA family showed differential accumulation in response to N starvation.

Those N-responsive miRNAs and their target genes are likely involved in the development or regulation of the adaptive response to N starvation. Their results suggested that changes in the expression levels of miR160, miR167, and miR171 may be important for the enhancement of plant root system under nitrogen deficiency. The identification of these N-starvation-responsive miRNAs provides new insights into the molecular mechanism of adaptation of plants to N deficiency.

The study entitled “Identification of Nitrogen Starvation-Responsive MicroRNAs in Arabidopsis thaliana” has been published in PLoS ONE 7(11): e48951. doi:10.1371/journal.pone.0048951