Construction of Agonistic Bivalent Double-Stranded Aptamers Targeting c-MET.

Area of Science:

• Molecular Biology
• Biochemistry
• Drug Discovery

Background:

• Aptamers are oligonucleotides with high-affinity binding but typically inhibit function.
• Activating aptamers are rare, limiting their therapeutic applications.
• c-MET signaling is crucial in cell processes but requires specific activation.

Purpose of the Study:

• To engineer a biologically inert aptamer into one with agonistic activity.
• To develop novel bivalent double-stranded aptamers (BVDSApts) targeting c-MET.
• To investigate the functional consequences of engineered aptamer-induced c-MET activation.

Main Methods:

• Rational molecular engineering of a known c-MET aptamer (HF3-58).
• Design and synthesis of bivalent double-stranded aptamers (BVDSApts) with varying central duplex lengths.
• Assessment of c-MET binding, dimerization, phosphorylation, and downstream signaling in cells.

Main Results:

• Engineered BVDSApts showed enhanced c-MET binding, unlike their single-stranded counterparts.
• Optimized BVDSApts (18-22 bp duplex) potently induced c-MET dimerization and phosphorylation.
• Induced signaling significantly enhanced cell migration and dispersion, mimicking HGF effects.

Conclusions:

• Biologically inert aptamers can be engineered into functional agonists through rational design and sequence engineering.
• BVDSApts represent a novel class of aptamers with the ability to activate target molecules.
• These engineered aptamers offer potential as therapeutic agents and precursors for HGF substitutes.