Targeting the cis-dimerization of LINGO-1 with low MW compounds affects its downstream signalling

Area of Science:

• Neuroscience
• Molecular Biology
• Pharmacology

Background:

• Leucine-rich repeat and Ig domain-containing protein 1 (LINGO-1) is a key regulator of neural function, impacting axonal regeneration, neuronal survival, and myelination.
• The precise molecular mechanisms governing LINGO-1's biological activity remain incompletely understood, particularly regarding its oligomeric state.

Purpose of the Study:

• To investigate the formation and functional significance of LINGO-1 cis-dimers.
• To identify small molecules that modulate LINGO-1 dimerization and its downstream signaling.

Main Methods:

• Co-immunoprecipitation and BRET saturation analysis were used to identify LINGO-1 homodimers in cell lines and primary neurons.
• A BRET-based assay was developed for high-throughput screening of small-molecule modulators.
• Downstream signaling effects were assessed using Western blotting and AlphaScreen technology.

Main Results:

• LINGO-1 forms constitutive homodimers in a cis-orientation, evident early in its biosynthesis.
• Phenoxybenzamine was identified as the first small molecule to modulate LINGO-1 dimer conformation.
• Phenoxybenzamine enhanced LINGO-1's inhibitory effects on EGF receptor signaling and Erk phosphorylation in HEK-293 cells.

Conclusions:

• LINGO-1 exists as constitutive cis-dimers at the plasma membrane, regulating key neural processes.
• Targeting the LINGO-1 dimerization interface with small molecules represents a novel pharmacological strategy.
• This approach offers new avenues for drug discovery in neurological disorders.