Dar et al. investigated transcription termination in archaea by sequencing the 3′ ends of the transcriptomes of the euryarchaeon Methanosarcina mazei and the crenarchaeon Sulfolobus acidocaldarius. A comparison with Bacillus subtilis revealed two interesting differences between archaea and bacteria. First, the lengths of 3′ UTRs were significantly longer in archaea than in B. subtilis. Second, 25−40% of genes in archaea had secondary transcription termination sites in addition to the primary site, whereas no such sites were detected in B. subtilis. These features of archaeal transcripts are reminiscent of transcript architectures that are commonly found in eukaryotic genes, in which alternative extended 3′ UTRs have a regulatory function by varying the provision of microRNA binding sites. Interestingly, 20 of 23 previously validated M. mazei non-coding RNAs had sequences with a potential for complementary binding with 14% of M. mazei 3′ UTRs, which may reflect a eukaryotic-like mechanism of gene regulation in archaea.