Circular RNAs (
circRNAs) have vital roles in great variety of biological processes. However, expression levels and functions of
circRNAs related to heat acclimation (HA) are poorly understood. This study is the first time an in-depth
circRNA expression profiling were used to investigate
circRNA-
miRNA interactions in HA rats in order to further comprehend the mechanisms underlying HA.
CircRNA expression profile was performed in rats' hypothalamus of HA and control group with microarray assays and their functions were predicted by using Bioinformatics analysis. Differential
circRNAs and their regulated downstream
miRNAs and mRNAs were quantitatively validated by means of quantitative polymerase chain reaction in real-time (RT-qPCR).
Enzyme-linked
immunosorbent assay (ELISA) was then applied to predict the expression of
proteins. In total, 53
circRNAs were expressed distinctively between the HA and Control; up- and down-regulation of
circRNAs were 28 and 25, respectively, in HA (fold change > 1.5, P < 0.05). Three
circRNAs and two
miRNAs and three predicted mRNAs were obviously regulated after validated by RT-qPCR in HA rats. Two
proteins expression were proportional to their
mRNA changes. Further analysis demonstrates that
circRNAs closest to HA can be categorized into three signal pathways: including rno_
circRNA_014301-vs-rno-miR-3575-vs-Hif-1α, rno_
circRNA_014301-vs-rno-miR-3575-vs-Lppr4, and rno_
circRNA_010393-vs-rno-miR-20b-3p-vs-Mfap4 in
hypoxia response pathways, substance/energy metabolism, and inflammatory response pathways. Our findings implicate that many
circRNAs regulate expressions of genes that interact with each other to exert their functions during HA.