COMPOSITIONS AND METHODS OF MUTANT NOGO-66 DOMAIN PROTEINS

摘要

To facilitate the study of Nogo-66 interaction with its neuronal receptors, and to explore therapeutic opportunities, the present invention provides mutant human Nogo-66 domain-based proteins that do not aggregate during isolation or purification procedures, and methods for using these proteins. To overcome aggregation problems of reagents having a wild-type human Nogo-66 domain, the invention provides proteins that comprise a mutant human Nogo-66 domain, wherein the cysteine at position 47 of the wild-type human Nogo-66 domain is mutated. Mutating position 47 from a cysteine to another amino acid, for example, valine, prevents Nogo-66 domain-based proteins from aggregating. Aggregate complexes of Nogo-66 domain containing proteins do not effectively or efficiently bind to NgRl , and therefore limit the utility of Nogo-66 domain-based reagents. The present invention also provides for various Nogo-66 domain fusion reporter proteins. These fusion reporter proteins are able to bind to the NgRl receptor, and therefore the fusion proteins can be used in high- throughput assays to identify drug candidate compounds that can block or out-compete binding of the Nogo-66 domain to NgRl, thereby indicating that these drug candidates may be potential therapeutic agents for neurodegenerative diseases and neuronal repair.