MicroRNA Shows Macro Potential
Courtesy of Bonnie Bartel and David P. Bartel Reprinted from Plant Physiol, 132:1-9, June 2003. CURRENT MODEL: (A) A microRNA (MIR) gene encodes a primary transcript with a stem-loop structure. A hairpin precursor (in brackets) has been found in animals but not in plants. The enzyme Dicer cleaves the transcript to form a microRNA (miRNA) which nestles in a ribonucleoprotein (RNP) complex that is similar, if not identical, to the RNA-induced silencing complex (RISC). (B) When an mRNA has n
Jun 15, 2003
Courtesy of Bonnie Bartel and David P. Bartel Reprinted from Plant Physiol, 132:1-9, June 2003. |
  |
 CURRENT MODEL: (A) A microRNA (MIR) gene encodes a primary transcript with a stem-loop structure. A hairpin precursor (in brackets) has been found in animals but not in plants. The enzyme Dicer cleaves the transcript to form a microRNA (miRNA) which nestles in a ribonucleoprotein (RNP) complex that is similar, if not identical, to the RNA-induced silencing complex (RISC). (B) When an mRNA has near-perfect complementarity to an miRNA, the mRNA is cleaved. (C) When an mRNA has less complementarity to an miRNA, the mRNA's translation is attenuated.  |
|
The RNA paradigm is due for another correction. Once, RNA seemed a mere conduit between genes and proteins. Its status expanded with reports of catalytic RNA 20 years ago and of endogenous RNA interference 10 years later. Now microRNAs, the 20- to 24-nucleotide transcripts that underlie much...
Interested in reading more?
Become a Member of
Receive full access to digital editions of The Scientist, as well as TS Digest, feature stories, more than 35 years of archives, and much more!
Already a member?