MicroRNA genes are transcribed by RNA polymerase II

Yoontae Lee, Minju Kim, Jinju Han, Kyu Hyun Yeom, Sanghyuk Lee, Sung Hee Baek, V. Narry Kim

Research output: Contribution to journalArticlepeer-review

3431 Scopus citations


MicroRNAs (miRNAs) constitute a large family of noncoding RNAs that function as guide molecules in diverse gene silencing pathways. Current efforts are focused on the regulatory function of miRNAs, while little is known about how these unusual genes themselves are regulated. Here we present the first direct evidence that miRNA genes are transcribed by RNA polymerase II (pol II). The primary miRNA transcripts (pri-miRNAs) contain cap structures as well as poly (A) tails, which are the unique properties of class II gene transcripts. The treatment of human cells with α-amanitin decreased the level of pri-miRNAs at a concentration that selectively inhibits pol II activity. Furthermore, chromatin immunoprecipitation analyses show that pol II is physically associated with a miRNA promoter. We also describe, for the first time, the detailed structure of a miRNA gene by determining the promoter and the terminator of mir-23a∼27a∼24-2. These data indicate that pol II is the main, if not the only, RNA polymerase for miRNA gene transcription. Our study offers a basis for understanding the structure and regulation of miRNA genes.

Original languageEnglish
Pages (from-to)4051-4060
Number of pages10
JournalEMBO Journal
Issue number20
StatePublished - 13 Oct 2004


  • Cap
  • Drosha
  • MicroRNA
  • Promoter
  • Transcription


Dive into the research topics of 'MicroRNA genes are transcribed by RNA polymerase II'. Together they form a unique fingerprint.

Cite this