Transcription of pol II genes can continue for hundreds or even thousands of nucleotides beyond the end of a noncoding sequence. The RNA strand is then cleaved by a complex that appears to associate with the polymerase. Cleavage seems to be coupled with termination of transcription and occurs at a consensus sequence. Mature pol II mRNAs are polyadenylated at the 3′-end, resulting in a poly(A) tail; this process follows cleavage and is also coordinated with termination.