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

Area of Science:

• Genetics and Molecular Biology
• Neuroscience
• Therapeutic Development

Background:

• Haploinsufficiency, caused by deficient gene expression, requires new therapeutic strategies.
• Increasing protein translation from existing mRNA offers a promising approach to restore physiological levels.
• Previous methods have not been tested in vivo for neurological disorders.

Purpose of the Study:

• To investigate the efficacy of a translational activator in a mouse model of Dravet syndrome.
• To engineer human proteins for programmable, guide RNA-directed mRNA translation using the CRISPR-Cas Inspired RNA-targeting System (CIRTS).
• To assess if increased translation of SCN1a mRNA can ameliorate disease phenotype.

Main Methods:

• Development of the CRISPR-Cas Inspired RNA-targeting System (CIRTS) platform with engineered human proteins.
• Identification of a compact translational activator (CIRTS-4GT3) capable of enhancing endogenous transcript translation.
• Adeno-associated virus (AAV)-mediated delivery of CIRTS-4GT3 targeting SCN1a mRNA in a Dravet syndrome mouse model.

Main Results:

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

Conclusions:

• This work validates translational activation as a viable strategy for addressing SCN1a haploinsufficiency.
• The CIRTS platform enables programmable enhancement of protein production for therapeutic benefit.
• Translational activation holds significant preclinical potential for treating neurological haploinsufficiency disorders.