From: Circular RNAs’ cap-independent translation protein and its roles in carcinomas
Categories | Composition characteristics | Main positioning | The main function | Ref. |
---|---|---|---|---|
CiRNAs | Intron splicing | Nucleus | Participate in regulating the expression of its parental genes | [20] |
EcircRNAs | Exon splicing | Cytoplasm | As a sponge of miRNA or interact with RBPs | [34] |
EIciRNAs | Contains introns and exons | Nucleus | Promote the transcription of its host gene by interacting with U1 small nuclear ribonucleoprotein (snRNP) | [22] |
f−circRNAs | Linear fusion transcript derived from genome rearrangement (chromosomal translocation) | Cytoplasm and nucleus | Contribute to cell transformation, promote cell viability and drug resistance after treatment, and have tumor-promoting properties in in vivo models | [23] |
rt− circRNAs | Coding exons of two adjacent and similarly oriented genes (read-through transcription) | Cytoplasm | To be elucidated, it may be a mechanism of gene regulation in a specific environment; it may be a mechanism of protein complex evolution | [26] |
mecciRNAs | Mitochondrial Genome | Mitochondria inside and outside | As a molecular chaperone, it helps to fold nuclear-encoded proteins and facilitate their entry into the mitochondria. | [45] |