MicroRNA Biogenesis

б к

2004. 5. 19

Hundreds of small RNAs of ~22-nt in length, collectively named microRNAs (miRNAs), have been discovered in animals and plants; whereas their functions, such as in developmental control, are being unraveled, their biogenesis mechanism remains poorly understood.

MicroRNAs (miRNAs) are transcribed as long primary transcripts (pri-miRNAs) which are then matured through at least two sequential events: the nuclear processing of the pri-miRNAs into stem-loop precursors of ~70-nt (pre-miRNAs) and the cytoplasmic processing of pre-miRNAs into mature miRNAs of ~22-nt. Dicer, a member of the Ribonuclease III (RNase III) superfamily of bidentate nucleases, mediates the latter step, whereas the processing enzyme for the former step remained unknown.

We recently identified another RNase III type protein, Drosha, as the core nuclease that executes the initiation step of miRNA processing in the nucleus. Further analysis indicated that Drosha predetermines the sequences of mature miRNA by precisely cropping pri-miRNA. The mechanism for the specific selection of cleavage sites will be discussed.

Although transcription is another key step in miRNA biogenesis, little is known about the transcriptional machinery and gene structure. We have characterized the structure of primary transcript of a miRNA and determined the promoter. Our data provide a critical insight into the transcriptional regulation of miRNA biogenesis.




2004-    б к

2001-2004    б BK21η¾缺

1999-2001    University of Pennsylvania, postdoctoral fellow

1994-1998    Oxford University ȭа, ڻ

1992-1994    б ̻а,

1988-1992    б ̻а, л


This page is maintained by Ji-seon Yoo (jsyoo@bi.snu.ac.kr).
Last update: November. 18, 2004