PMO Oligonucleotides Block Let-7c miRNA Binding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current therapeutic approaches for Duchenne Muscular Dystrophy (DMD) face challenges in effectively upregulating utrophin protein expression due to limitations in pharmacokinetic properties and side effects associated with existing oligonucleotide treatments, such as 2'OMePS-based SBOs and antisense oligonucleotides.
Innovation Solution
Design and administration of Let-7c PMO-based SBOs that target different overlapping regions of the Let-7e binding site in the UTRN 3'UTR to inhibit microRNA binding, thereby enhancing utrophin protein production and reducing dystrophic phenotypes in DMD models.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If 2'OMePS-based site blocking oligonucleotides (SBOs) are used to block Let-7c binding site, then utrophin protein expression is upregulated, but pharmacokinetic properties deteriorate due to charged nature of 2OMePS
Solution Approach 1:
The patent changes the chemical parameters of the oligonucleotide backbone from charged 2'OMePS to uncharged phosphorodiamidate morpholino (PMO) groups. This parameter change eliminates the charge-related pharmacokinetic limitations while preserving the ability to block microRNA binding sites and upregulate utrophin expression.
Solution Approach 2:
The patent uses composite chemical structure combining morpholino rings with phosphorodiamidate linkages to create PMO oligonucleotides. This composite material approach provides both the structural stability needed for effective target binding and the neutral charge properties that improve pharmacokinetic behavior in vivo.
2Reliability
If dystrophin exon 51 skipping 2OMePS antisense oligonucleotides (AONs) are administered, then improvements in DMD are achieved, but side effects occur including proteinuria and moderate thrombocytopenia
Solution Approach 1:
The patent changes the chemical nature of the oligonucleotide from charged 2OMePS to uncharged PMO, which reduces non-specific interactions with cellular components and plasma proteins. This parameter change maintains therapeutic efficacy through specific target binding while reducing off-target side effects such as proteinuria and thrombocytopenia.
3Quantity of substance
If multiple overlapping PMO-based SBOs targeting different regions of Let-7e binding site are designed, then utrophin upregulation efficacy is improved, but device complexity increases
Solution Approach 1:
The patent divides the Let-7c/Let-7e binding site in the utrophin 3'UTR into multiple overlapping target regions, and designs separate PMO oligonucleotides for each region. This segmentation allows comprehensive coverage of the binding site, ensuring robust blocking of microRNA activity and consistent utrophin upregulation across different sequences.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The Let-7c PMO-based SBOs demonstrate significant utrophin upregulation in both cell line and animal models, showing improved dystrophic pathophysiology with reduced muscle degeneration and serum CK levels, indicating a promising therapeutic strategy for DMD.
Implementation Method 1
an oligonucleotide that specifically hybridizes to a Let-7c microRNA binding sequence in a utrophin mRNA 3'-untranslated region (UTR) and inhibits binding of the Let-7c microRNA to the utrophin mRNA 3'-UTR
Data Source
AI summary
The present disclosure provides methods and compositions for enhancing utrophin protein production by inhibiting binding of a Let-7c microRNA molecule to its binding site in the utrophin mRNA 3′-untranslated region (UTR). In particular, phosphorodiamidate morpholino oligonucleotide (PMO) site blocking oligonucleotides (SBOs) that inhibit Let-7c miRNA binding to its binding site in the utrophin mRNA 3′UTR. Moreover. methods of enhancing utrophin protein production in muscle cells can be used to treat muscular dystrophy and/or other myopathies.