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Nobel price 2006
"for their discovery of RNA interference - gene silencing by
double-stranded RNA"
Andrew Z. Fire
Craig C. Mello
USA
USA
Stanford University
School of Medicine
Stanford, CA, USA
University of Massachusetts
Medical School
Worcester, MA, USA
Serendipity?
Potent and specific genetic interference by double-stranded
RNA in Caenorhabditis elegans
Andrew Fire, SiQun Xu, Mary K. Montgomery,Steven A. Kostas,
Samuel E. Driver & Craig C. Mello
NATURE | VOL 391 | 19 FEBRUARY 1998
They worked on something else in C. elegans
Gene expression – sense RNA (control)
Gene silencing – antisense RNA (weak effect)
One more controla with double strand (s-as) RNA,
SURPRISE – IT WORKED VERY WELL
Nobelova price experiment
dsRNA blocks target mRNA
asRNS
dsRNS
Not absolute new
Drosophila (Elbashir, EMBO J, 2001, Genes and Dev, 2001)
dsRNA → 21-23 nt small dsRNA
small interferring RNA – siRNA
siRNS
21-25 nt dsRNA
from a bigger dsRNA precursor molecule
These are coded in genome – also in ours
C. elegans (Lee, 1993, Cell)
NON CODING SEQUENCES!
SMALL (61 → 22nt) RNA
lin-14 mRNS 3’ UTR komplementerita
REGULATION OF GENE EXPRESSION
microRNA (miRNA)
miRNS biogenesis
The code is transcribed by RNA polymerase II
More possibilities
– separated - 1 miRNA
– clusters
– in INTRONS!
Mendell, 2008, Cell
Biogenesis and effect of siRNA
Dykxhoorn, 2003, Nat Rev Mol Cell Biol
Finalisation of siRNA
• With protein complexes (coded in genome)
– Dicer makes siRNA (+ATP)
– RISC – komplex with siRNA, cuts mRNA
(+ATP)
– Argonauta – blocks translation
siRNA effect
Eckstein, 2005, TIBS
Another possibility
Inhibícia translácie
miRNA - functions
In human genome at least 500 – 1000 miRNa genes
1-1,5 % of all structural genes
A new (?) form of gene expression regulation – on the interface of
transcription and translation
THE LAST CHECKPOINT (SMALL NINJA POLICIMEN)
miRNA expression regulation????
tissue specificity, dependent on ontogenesis
Involved in
Development, differentiation, apoptosis, cell cycle
miRNA functions
One miRNA can regulate more mRNA (Lim, 2005, Nature)
In different conditions different picture of expression
miR-1 – heart, miR-124 – brain
In vitro experiments
miR-1 96, miR124 downregulated 174 génov
miRNA and disease
miRNA profiles different in normal and malignant cells
miRNA profiles in diabetes, cardiovascular and kidney diseases,
degenerative disease of CNS – intensive research currently
without aplication in practical medicine
SNPs in miRNA genes and disease???
Therapeutical perspectives?
Malignancies
Farmakogenetics
Design of artifical siRNA?
Not a simple task
Get them to the proper place – nanobiotechnology
Fewell, 2006, Drug Discovery