At the very begining, total RNA was reverse transcription by random prime and b-actin was select to be the housekeeping gene. BUT i fail to get amplification with all cirRNA without one which CT value is 8. I think something maybe wrong with my experiment. I think maybe I should use RNase R to make the enrichment. But RNase R could degradation of all linear RNA, could I also use b-actin to be the housekeeping gene in qPCR assay? B-actin mRNA may not be digest by RNase? Which gene should be use in this condition? thanks?