6C RNA is a class of non-coding RNA present in actinomycetes. 6C RNA was originally discovered as a conserved RNA structure having two stem-loops each containing six or more cytosine (C) residues. Later work revealed that 6C RNAs in Streptomyces coelicolor and Streptomyces avermitilis have predicted rho-independent transcription terminators, and microarray and reverse-transcriptase PCR experiments indicate that the S. coelicolor version is transcribed as RNA. Transcription of the S. coelicolor RNA increases during sporulation, and three transcripts were detected that overlap the 6C motif, but have different apparent start and stop sites.