Identification of Drought-Responsive CircRNAs in Leaves of Brachypodium distachyon

Abstract

Brachypodium distachyonis currently recognized as a model organism in Gramineae, especially for temperate grains. Research on its dehydrationresponse mechanism is beneficial for elucidating the complex drought regulation network in temperate grains. The circRNA is an important type of non-coding RNA in organisms, which could involve in various biological processes. By sequencing the transcriptome of the leaves of B. distachyonunder desiccationtreatmentand normal condition, a total of 737 circRNAs were obtained in this study, of which 332 and 265 were up-regulated and 265 down-regulated, respectively, with 140 insignificant differences. There were 229 and 303 circRNAs specifically expressed under CK and drought,respectively and 204 were co-expressed. Bioinformatics methods were used to identify potential miRNA targets of differentially expressed circRNAs. Among them, 150 differentially expressed circRNAs had putative miRNA binding sites. According to the predicted miRNA with binding site, the target genes downstream of the miRNA were screened. In terms of the functional annotation of target genes, they are divided into seven categories: hormone-related, photosystem, stress response, regulation factor, ion transport, TF and ribosomal protein. These circRNAs involved in water deficitresponse may play a significant role in the drought response and defense of B. distachyon. This also provides new insights for the improvement of the dehydration regulation mechanism of B. distachyonand even temperate grains.© 2021 Friends Science Publishers