Differential expression of circRNAs in the three stages of heart failure in TAC mice

To identify the role of circRNA on the mouse heart during pressure overload induced heart failure, we have employed circRNA microarray expression profiling as a discovery platform to detect circRNA expression. Samples were collected from the sham group and the pressure overload groups (2, 4 and 8 weeks after TAC), with 2 samples per group. The candidate circRNA that may affect the process of heart failure was screened by comparing the pressure overload groups and the sham group. Arraystar mouse circular RNA array V2 was used to profile circRNA expression in murine hearts during cardiac remodeling progression. After isolation, the total RNAs were digested with RNase R to remove linear RNAs and enrich circular RNAs. The latter were further amplified and transcribed by random priming into fluorescent cRNA. The labeled cRNA concentration and activity in pmol Cy3/μg cRNA were measured. One microgram of each labeled cRNA was fragmented, heated, and assembled onto the Arraystar Mouse circular RNA Array V2 (8x15K; Agilent Technologies). The arrays were hybridized, washed, fixed, scanned with an Agilent scanner (No. G2505C; Agilent Technologies), and analyzed with Agilent feature extraction software v.11.0.1.1 (Agilent Technologies).