Table 1.

The published databases related to circRNAs

Database	Link	Function	Ref.
circBase	http://www.circbase.org/	The circRNA information predicted by large-scale studies, including the circRNA sequences, etc.	[7]
Circbank	http://www.circbank.cn/	Provide a new nomenclature system and collect other five features of circRNAs, including miRNA binding sites, conservation across species, m6A modification, mutations in circRNAs, and predicted ORFs and IRESs	[10]
Circ2Traits	http://gyanxet-beta.com/circdb	The disease-related miRNA–circRNA–mRNA–lncRNA interaction networks	[11]
starBase v2.0	http://starbase.sysu.edu.cn/	Systematically identify the RNA–RNA and protein–RNA interaction networks	[9]
CircInteractome	https://circinteractome.nia.nih.gov	Predict the interactions between miRNAs and circRNAs with 109 RBPs, and the database also focus on IRESs and ORFs	[8]
circNet	http://syslab5.nchu.edu.tw/CircNet	Focus on the tissue-specific circRNA expression profiles and circRNA–miRNA–mRNA regulatory networks	[12]
deepBase2.0	http://biocenter.sysu.edu.cn/deepBase/	Comparison of non-coding RNAs including sRNA, lncRNA, and circRNA across 19 species	[13]
circRNADb	http://reprod.njmu.edu.cn/circrnadb	Report exon splicing information of exon circRNAs and predict IRESs	[14]
TSCD	http://gb.whu.edu.cn/TSCD	Collect tissue-specific circRNAs in tissues of human and mouse, circRNA–miRNA interactions, predicted RBP binding sites, etc.	[15]
PlantcircBase	http://ibi.zju.edu.cn/plantcircbase	Plant circRNAs	[16]
PlantCircNet	http://bis.zju.edu.cn/plantcircnet	The expression profiles of plant circRNAs, circRNA–miRNA–gene regulatory networks, etc.	[17]
circlncRNAnet	http://120.126.1.61/circlnc/index.php	The co-expression network of lncRNA and circRNA, and the information of miRNA binding and RBP binding sites	[18]
exoRBase	http://www.exoRBase.org	The circRNAs, lncRNAs, and mRNAs in human blood exosomes	[19]
CSCD	http://gb.whu.edu.cn/CSCD	Provide cancer-specific circRNAs and circRNA–miRNA interactions; predict cellular location, RBP binding sites, and ORFs	[20]
CIRCpedia v2	http://www.picb.ac.cn/rnomics/circpedia	Focus on circRNA annotation, expression comparison, and conservation between humans and mice	[21]
CircFunBase	http://bis.zju.edu.cn/CircFunBase	Collect experimentally validated and predicted functions of circRNAs, and circRNA-associated miRNAs and RBPs in plants and animals	[22]
CropCircDB	http://genome.sdau.edu.cn/crop/	Investigate circRNAs under stress condition in maize and rice	[23]
GreenCircRNA	http://greencirc.cn/	Plant circRNAs acting as miRNA decoys, and their potential networks involving circRNA–miRNA–mRNA in the corresponding species	[24]
VirusCircBase	http://www.computationalbiology.cn/ViruscircBase/home.html	Focus on the survey of circRNAs from viral species	[25]
CircAtlas	http://circatlas.biols.ac.cn/	Describe multiple conservation, co-expression, and circRNA annotation and prioritization	[26]
MiOncoCirc	https://mioncocirc.github.io/	The first database to be composed primarily of circRNAs directly detected in tumor tissues	[27]
circRic	https://hanlab.uth.edu/cRic/	Characterize circRNA expression profiles; analyze the circRNA biogenesis regulators, the effect of circRNAs on drug response, the association of circRNAs with mRNAs, proteins, and mutations, etc.	[28]
LncRNADisease 2.0	http://www.rnanut.net/lncrnadisease/	Host disease-associated lncRNAs and circRNAs	[29]
riboCIRC	http://www.ribocirc.com	Provide computationally predicted ribosome-associated circRNAs and experimentally verified translated circRNAs	[30]
ClinVAR	http://soft.bioinfo-minzhao.org/circvar	Collect SNPs and small insertions and deletions in putative circRNA regions	[31]
TransCirc	https://www.biosino.org/transcirc/	Provide comprehensive evidence supporting the translation potential of circRNAs	[32]

Note: ORF, open reading frame; IRES, internal ribosome entry site; RBP, RNA-binding protein; lncRNA, long non-coding RNA; SNP, single nucleotide polymorphism.