Characterization and Cloning of Grape Circular RNAs Identified the Cold Resistance-Related Vv-circATS1

Abstract

Circular RNAs (circRNAs) are widely distributed and play essential roles in a series of developmental processes, although none have been identified or characterized in grapevines (Vitis vinifera). In this study, we characterized the function of grape circRNA and uncovered thousands of putative back-splicing sites by global transcriptome analysis. Our results indicated that several reported circRNA prediction algorithms should be used simultaneously to obtain comprehensive and reliable circRNA predictions in plants. Furthermore, the length of introns flanking grape circRNAs was closely related to exon circularization. Although the longer introns flanking grape circRNAs appeared to circularize more efficiently, a 20-to 50-nt region seemed large enough to drive grape circRNA biogenesis. In addition, the endogenous introns flanking circularized exon(s) in conjunction with reverse complementary sequences could support the accurate and efficient circularization of various exons in grape, which constitutes a new tool for exploring the functional consequences caused by circRNA expression. Finally, we identified 475 differentially expressed circRNAs in grape leaves under cold stress. Overexpression of Vv-circATS1, a circRNA derived from glycerol-3-P acyltransferase, improved cold tolerance in Arabidopsis (Arabidopsis thaliana), while the linear RNA derived from the same sequence cannot. These results indicate the functional difference between circRNA and linear RNA, and provide new insight into plant abiotic stress resistance.

Systematic identification and analysis of heat‐stress‐responsive lncRNAs, circRNAs and miRNAs with associated co‐expression and ceRNA networks in cucumber (Cucumis sativus L.)

“…Plant circRNAs showed different expression patterns, and 27 rice exonic circRNAs were found to be differentially expressed under phosphate‐sufficient and ‐starvation conditions (Ye et al ). Overexpression of Vv‐circATS1, a circRNA derived from glycerol‐3‐P acyltransferase (ATS1), improved cold tolerance in Arabidopsis, while the linear RNA derived from the same sequence is not able to do the same (Gao et al ). Recently, transcriptome analyses of plant drought response and transgenic studies in Arabidopsis thaliana have revealed a relationship between circRNA expression and drought resistance, indicating that circRNAs play a key role in plant drought resistance responses and can also be used as effective biomarkers for genetic improvement of crop drought resistance (Zhang et al , ).…”

circRNAs Are Involved in the Rice-Magnaporthe oryzae Interaction

“…Plant circRNAs have been found to function during fiber development, flowering, and fruit coloration based on spatial-and/or tissue-specific expression patterns (Tan et al, 2017;Wang et al, 2017c;Tong et al, 2018). The expression of plant circRNAs also responds to abiotic and biotic stimuli, including pathogen invasion (Zuo et al, 2016;Wang et al, 2017c;Zhou et al, 2017;Ghorbani et al, 2018;Xiang et al, 2018;Gao et al, 2019). For example, the accumulation of a set of circR-NAs is altered in kiwifruit upon canker pathogen infection (Wang et al, 2017c).…”

Identification and Characterization of circRNAs Responsive to Methyl Jasmonate in Arabidopsis thaliana

“…However, the roles of circRNAs in MeJA-mediated signaling pathways in A. thaliana have not been reported. Similar to other stresses in various plants, such as drought stress in maize and A. thaliana [20], dehydration stress in wheat [25], and cold stress in grapevine [28], MeJA treatment in A. thaliana altered the expression profiles of circRNAs. In this study, among the 8588 identified circRNAs, 385 circRNAs were identified as DEcircRNAs between MeJA-treated and untreated seedlings.…”

“…Recently, with the development of high-throughput sequencing technology, increasing numbers of circRNAs have been detected in plants and animals. In plants, circRNAs are closely related to plant development and stress responses, including biotic and abiotic stresses [20,[22][23][24][25][26][27][28]30,53]. However, whether circRNAs participate in the pathways of plant responses to hormones is unclear.…”

“…Furthermore, although most circRNAs are considered to be noncoding RNAs, some circRNAs undergo cap-free translation under certain conditions [14]. Recently, increasing numbers of circRNAs have been detected in Arabidopsis thaliana [15][16][17], maize [18][19][20], rice [15,21], tomato [22][23][24], wheat [25][26][27], and grape [28], indicating that circRNAs are widespread in plants. Plant circRNAs are as conserved and tissue specific as animal circRNAs, but their flanking introns do not contain as many repetitive elements and reverse complementary sequences as those in animals [15,16,19,29].…”