AUTHOR=Li Hao , Dong Yuchuan , Chang Jingjing , He Jie , Chen Hejie , Liu Qiyan , Wei Chunhua , Ma Jianxiang , Zhang Yong , Yang Jianqiang , Zhang Xian 

TITLE=High-Throughput MicroRNA and mRNA Sequencing Reveals That MicroRNAs May Be Involved in Melatonin-Mediated Cold Tolerance in Citrullus lanatus L.

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.01231

DOI=10.3389/fpls.2016.01231

ISSN=1664-462X

ABSTRACT=<p>Transcriptional regulation of cold-responsive genes is crucial for exogenous melatonin-mediated cold tolerance in plants. Nonetheless, how melatonin regulates cold-responsive genes is largely unknown. In this study, we found that exogenous melatonin improved cold tolerance in watermelon by regulating expression of microRNAs (miRNAs). We identified a set of miRNAs that were regulated by melatonin under unstressed or cold conditions. Importantly, mRNA-seq analysis revealed that melatonin-induced downregulation of some miRNAs, such as <italic>miR159-5p</italic>, <italic>miR858</italic>, <italic>miR8029-3p</italic>, and <italic>novel-m0048-3p</italic> correlated with the upregulation of target genes involved in signal transduction (CDPK, BHLH, WRKY, MYB, and DREB) and protection/detoxification (LEA and MDAR) under cold stress. These results suggest that miRNAs may be involved in melatonin-mediated cold tolerance in watermelon by negatively regulating the expression of target mRNAs.</p>