The circRNA interactome-innovative hallmarks of the intra- and extracellular radiation response.

Generated by Quaking (QKI), circular RNAs (circRNAs) are newly recognised non-coding RNA (ncRNA) members characterised by tissue specificity, increased stability and enrichment within exosomes. Studies have shown that ionizing radiation (IR) can influence ncRNA transcription. However, it is unknown whether circRNAs or indeed QKI are regulated by IR. Microarray circRNA profiling and next generation sequencing revealed that circRNA expression was altered by low and medium dose exposure sourced predominantly from genes influencing the p53 pathway. CircRNAs and transcribed from the () tumor suppressor (a p53 regulator) responded within hours to IR. and were present in exosomes yet exhibited differential transcript clearance between irradiated cell lines. Dual-quasar labelled probes and hybridization demonstrated the intercellular distribution of and predominantly within the perinucleus. QKI knockdown removed nuclear expression of these circRNAs with no significant effect on cytosolic and Distinct QKI transcription between cell lines and its augmented interaction with and was noted post IR. This foremost study provides evidence that QKI and circRNAs partake in the cellular irradiation response. and as stable secreted circRNAs may afford vital characteristics worth syphoning as promising diagnostic radiotherapy biomarkers.