Circular RNA (circRNA) is a novel type of RNA that, unlike linear RNA, forms a covalently closed continuous loop, some of which are highly represented in the eukaryotic transcriptome. Most of these circRNAs are generated from exonic or intronic sequences, are conserved across species, and often show tissue/developmental-stage-specific expression. Circular RNAs are more stable than linear RNAs owing to their higher nuclease stability, which constitutes an enormous advantage from a clinical point of view as a novel class of biomarkers. In addition, circRNAs have been shown to function as natural miRNA sponges , the so-called competing endogenous RNAs (ceRNAs). Their interaction with disease associated miRNAs suggests the potential importance of circular RNAs in disease regulation.
To facilitate the analysis of circRNAs, Arraystar has developed the first commercially -available circRNA microarrays. All the circular RNAs with stringent experimental support are carefully and comprehensively curated from the most recent published studies. In addition, rat orthologs of the known human and mouse circRNAs are predicted and included.The circRNAs are annotated with predicted miRNA target sites to help unravel their functional roles as a natural miRNA sponge. Each circRNA is represented by a circular splice junction probe that can detect the circRNA reliably and accurately, even in the presence of its linear counterparts. Random primer-based labeling is coupled with RNase R sample pre-treatment to ensure specific and efficient labeling of circular RNAs. RNA spike-in controls are included to monitor the labeling and hybridization efficiencies.
The rat circular RNA microarray allows systematic profiling of the circRNA transcriptome to spearhead your research in rats as human disease and physiology models, in areas such as cardiovascular, central nervous system, cancer and reproduction systems.
• Specific Circular Junction Probes
Reliably and accurately identify individual circRNAs, even in the presence of their linear counterparts (Fig. 1).
Figure 1. Arraystar circRNA Microarray V2.0 uses specific circular junction probes to accurately and reliably detect each individual circRNAs, even in the presence of their linear counterparts. The linear RNA at the bottom is alternatively processed to generate a circular variant above. A probe is designd to target the circRNA-specific junction site, where the 5' end of exon A joins together with the 3' end of exon B.
• Detailed annotation for circRNA-miRNA association
Annotation of potential miRNA target sites on the circular RNAs helps to unravel their functional roles as a natural miRNA sponge (Fig. 2).
Figure 2. The association between circular RNA and conserved miRNAs is annotated in detail.
• The preferred choice over RNA-sequencing, as RNA-seq is currently inadequate for such task due to the particular properties of circular RNA. Learn more >
Figure 3. RNA-seq quantification reliability vs read depth. Typical RNA-seq has a depth of < 30 mil reads for mRNAs (blue circle), which is < 0.5 mil for cross circular junction reads (red circle). Less than 5% circular junctions can be reliably quantified. Adopted from Labaj et al, (2011) Bioinformatics [PMID 21685096].
• Spike-in RNA controls
A set of exogenous RNA controls developed by the External RNA Controls Consortium (ERCC) are added to the RNA samples. With the spike-in controls, procedural effects occurring during RNA amplification, labeling, and hybridization can be corrected. The limit of detection is more accurately determined, and the results across samples are compared more reliably.
• Guaranteed performance
- Better sensitivity: Low abundance RNAs are accurately detected with a wide dynamic range of over 5 orders of magnitude.
- High Reproducibility: Technical replicates show tight correlation on Arraystar circRNA microarrays (R2>0.9).
|Total Number of Distinct Probes
|Probe Selection Region
||Probes targeting circRNA-specific junctions
||Random primer labeling coupled with RNase R sample pretreatment to ensure specific and efficient labeling of circular RNAs.
|You Xintian's circRNAs 
|Mouse circRNA orthologs
|Human circRNA orthologs
||8 * 15K
1. You X., I. Vlatkovic, et al. (2015). "Neural circular RNAs are derived from synaptic genes and regulated by development and plasticity." Nat Neurosci 18(4): 603-610. .