gRNA Vector Generation via Rolling Circle Replication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for generating gRNA vectors and libraries are labor-intensive, error-prone, and result in reagents with severe sequence bias and cloning artifacts, making it difficult to create complex gRNA libraries for genetic screens.
Innovation Solution
A method for generating covalently closed circular (ccc) DNA-based small RNA/DNA expression vectors and vector libraries using mutagenic RNA or DNA primers, which allows for the easy construction of vector constructs with fixed pairs of gRNAs and the creation of vector libraries for genome editing applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional methods are used to generate gRNA vectors and libraries, then the process can be performed with standard techniques, but the process becomes labor-intensive and error-prone with severe sequence bias and cloning artifacts
Solution Approach 1:
The patent replaces conventional mechanical cloning methods (restriction enzymes, ligation, transformation) with a biochemical approach using T7 DNA polymerase for primer extension and rolling circle replication. This substitution eliminates the need for traditional cloning steps, reducing labor intensity and cloning artifacts while maintaining high accuracy and enabling scalable library generation.
Solution Approach 2:
The patent changes the biochemical parameters of the vector generation process by using T7 DNA polymerase with specific dNTP concentrations and temperatures (37°C for primer extension, 16°C for rolling circle replication). These parameter changes enable high-fidelity DNA synthesis and amplification without conventional cloning steps, resolving the contradiction between reliability and productivity.
2Manufacturing precision
If conventional cloning methods are used, then standard laboratory techniques can be applied, but sequence bias and cloning artifacts severely affect the quality of generated libraries
Solution Approach 1:
The patent extracts and eliminates the problematic cloning steps (restriction digestion, ligation, and multiple transformation steps) from the vector construction process. By using T7 DNA polymerase-based primer extension and rolling circle replication, the method directly generates correct sequences without the artifacts introduced by conventional cloning, thereby improving manufacturing precision while simplifying the overall process complexity.
Solution Approach 2:
The patent uses T7 DNA polymerase to create accurate copies of the gRNA sequences through primer extension and rolling circle replication. This copying mechanism ensures high-fidelity sequence reproduction without the errors and biases introduced by conventional cloning methods, achieving high manufacturing precision with a simplified process.
3Adaptability or versatility
If complex gRNA libraries are generated for genetic screens, then comprehensive genome coverage can be achieved, but the process becomes more difficult and error-prone
Solution Approach 1:
The patent creates a universal vector system that can accommodate any gRNA sequence through the use of a standardized T7 promoter and multiple cloning site. This universal platform enables the generation of complex gRNA libraries with comprehensive genome coverage while maintaining high reliability through the robust T7 DNA polymerase-based amplification method that is not susceptible to sequence-specific biases.
Solution Approach 2:
The patent incorporates quality control feedback through the use of T7 DNA polymerase's high fidelity and the ability to easily verify library quality through sequencing. The method allows for monitoring and adjustment of library complexity and quality, ensuring that comprehensive genetic screens can be performed with high-reliability gRNA libraries.
Data Source
AI summary
The present invention pertains to a novel method for the generation of a vector construct suitable for gene editing applications which comprises a fixed pair of predetermined expressible guide RNA (gRNA) sequences. The method of the invention allows for an easy construction of such vectors and provides in addition thereto vector libraries for the expression of fixed pairs of gRNAs. The vectors of the invention may be advantageously used to cut out larger genomic DNA sequences, or alternatively, to simultaneously introduce mutations in the genome without a loss or larger genomic sequences. Hence, the system of the invention provides for many molecular genetic approaches for genome alteration.