Engineering a human-based translational activator for targeted protein expression restoration.

Area of Science:

• Molecular Biology
• Neuroscience
• Gene Therapy

Background:

• Haploinsufficiency, caused by deficient gene expression, requires new therapeutic strategies.
• Increasing protein production by enhancing messenger RNA (mRNA) translation is a potential therapeutic avenue.
• This approach has not been previously evaluated in an in vivo disease model.

Purpose of the Study:

• To investigate if a translational activator can improve the phenotype in a Dravet syndrome mouse model.
• To determine if increasing the translation of SCN1a mRNA can correct gene expression deficits.
• To validate targeted translational activation as a therapeutic strategy for neurological haploinsufficiency.

Main Methods:

• Utilized the CRISPR-Cas-inspired RNA-targeting system (CIRTS) platform to engineer human proteins for programmable mRNA translation activation.
• Identified a compact CIRTS translational activator (CIRTS-4GT3) capable of increasing translation of endogenous transcripts.
• Administered AAV-delivered CIRTS-4GT3 targeting SCN1a mRNA to a Dravet syndrome mouse model.

Main Results:

• CIRTS-4GT3 demonstrated targeted and sustained translation increases up to 100% for relevant epilepsy and neurodevelopmental disorder transcripts.
• Delivery of CIRTS-4GT3 to the Dravet syndrome mouse model resulted in increased SCN1a translation.
• Significant improvements in survivability and seizure threshold were observed in the treated mouse model.

Conclusions:

• This study validates targeted translational activation as a viable strategy to address SCN1a haploinsufficiency.
• The findings highlight the preclinical potential of engineered human proteins and the CIRTS platform for treating neurological disorders.
• Programmable translational activation offers a promising therapeutic approach for diseases stemming from deficient gene expression.