Synthesis and use of anti-reverse phosphorothioateanalogs of the messenger rna cap.

摘要

New RNA cap analogs are disclosed containing one or more phosphorothioates
groups. The analogs also contain
modifications at the 2''-O position of 7-methylguanosine that prevent them from
being incorporated in the reverse orientation during
in vitro synthesis of mRNA and that hence are "anti-reverse cap analogs"
(ARCAs). The ARCA modification ensures that the S atom
is precisely positioned within the active sites of cap-binding proteins in
both the translational and decapping machinery. The new
S-ARCA analogs are resistant to in vivo decapping enzymes. Some S-ARCAs have a
higher affinity for eIF4E than the corresponding
analogs not containing a phosphorothioate group. When mRNAs containing the
various S-ARCAs are introduced into cultured cells,
some are translated as much as five- fold more efficiently than mRNAs
synthesized with the conventional analog m7GpppG.