Biology Reference
In-Depth Information
The open problems have to a large extent remained unchanged: what is
a miRNA, and what parameters determine the efficacy of a miRNA tar-
get site in mRNA degradation or translational repression? As answers to
these questions start to emerge, the focus is shifting to the structure of
the microRNA nucleoprotein (miRNP) code. Such a code is believed to
control gene expression at the posttranscriptional level, similar to the
transcription regulatory code implemented at the DNA level.
137
At this
point, this analogy has relatively little experimental basis because the
equivalents at the RNA level of the multi-molecular complexes imple-
menting the combinatorial transcription control have not been character-
ized. Biochemical characterization of such complexes and identification
of binding sites of miRNA- and RNA-binding proteins using, again,
high-throughput data and computational analyses will start uncovering
this code in the very near future.
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