Linear Amplification of Short Nucleic Acids via Controlled Thermocycling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current amplification strategies, such as PCR, are inadequate for amplifying short nucleic acid sequences like micro RNAs due to their low Tm values and high concentration dependencies, making it difficult to analyze these molecules effectively, especially in low concentrations found in single cells.
Innovation Solution
A method involving a reaction mixture with target-specific primers and an enzyme that catalyzes primer extension, combined with osmolytes like betaine, which stabilizes the enzyme and primer-template duplexes, allowing for linear amplification of short nucleic acid sequences through controlled thermocycling, optimizing conditions such as temperature and denaturation time to enhance enzyme and RNA stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If PCR amplification is used for short nucleic acids, then amplification capability is improved, but reliability deteriorates due to low Tm values and high concentration dependencies
Solution Approach 1:
The patent changes the fundamental amplification mechanism from exponential PCR to linear amplification, and modifies reaction parameters including using S1 nuclease treatment, specific primer designs, and controlled thermocycling conditions to achieve reliable amplification of short nucleic acids that are incompatible with traditional PCR
Solution Approach 2:
The patent extracts and eliminates the problematic exponential amplification step of PCR that causes reliability issues with short nucleic acids, retaining only the essential primer extension and selection steps that provide reliable amplification for short sequences
2Productivity
If thermocycling is applied to amplify short nucleic acids, then amplification efficiency is improved, but enzyme stability deteriorates due to thermal degradation
Solution Approach 1:
The patent employs periodic thermocycling with controlled temperature segments (annealing at 10-30°C and denaturation at 35-60°C) that provides sufficient heat for amplification while limiting cumulative thermal stress on the enzyme through optimized cycle parameters and durations
Solution Approach 2:
The patent protects enzyme stability by using buffer conditions and controlled cycling parameters that preemptively reduce thermal damage accumulation, maintaining enzyme activity throughout multiple amplification cycles
3Speed
If standard amplification conditions are used, then amplification speed is improved, but measurement precision deteriorates for low-concentration samples
Solution Approach 1:
The patent performs preliminary linear amplification of low-concentration short nucleic acids before analysis, enriching the target molecules to detectable levels while maintaining the ability to distinguish true signals from background noise, thereby enabling precise measurement of low-abundance targets
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
This approach enables efficient multiplexed amplification of short nucleic acids, including micro RNAs, even from low-copy-number samples, by maintaining enzyme activity and preventing thermal degradation, thereby facilitating their analysis and profiling.
Implementation Method 1
an enzyme that catalyzes target-specific primer extension
Implementation Method 2
cycling the reaction mixture for at least 20 cycles between an annealing temperature segment of 10 C-30 C, and a denaturation temperature segment of 35 C-60 C
Data Source
AI summary
The present teachings provide novel methods for amplifying short nucleic acids. In some embodiments, the present teachings provide novel methods for linearly amplifying a collection of micro RNAs by using temperature cycling during a reverse transcription reaction. The cycling can comprise at least 20 cycles of an annealing temperature segment of 10 C-30 C, and a denaturation temperature segment of 35 C-60 C. In some embodiments, the temperature cycled reaction can comprise an osmolyte.