GRF Transcription Factor Editing at miR396 Sites for Higher Grain Yield

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for modifying Growth Regulating Factor (GRF) transcription factors in plants do not effectively enhance plant growth or grain yield, particularly through targeted manipulation of miR396 binding sites to increase mRNA levels and promote cell proliferation.

Innovation Solution

Introduce specific mutations or genomic modifications in the miR396 binding sites of GRF transcription factor genes using a CRISPR-associated effector protein and cytidine or adenosine deaminase, reducing miR396 binding and increasing GRF mRNA levels, thereby enhancing plant growth and grain yield.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If miR396 binding sites in GRF transcription factor genes are left unmodified, then the plant maintains natural gene regulation, but GRF mRNA levels remain limited and plant growth enhancement is insufficient

Engineering Contradiction:

Improveplant growth and grain yieldVSAvoidGRF mRNA levels

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The patent applies parameter changes by modifying the nucleotide sequence parameters at the miR396 binding sites in GRF transcription factor genes. Specific base substitutions are introduced to alter the binding affinity between miR396 and the target mRNA, thereby changing the degradation rate and stabilizing GRF mRNA to achieve higher expression levels and enhanced plant growth

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent extracts the miR396 binding sites from the GRF gene sequences and applies targeted mutations to these specific regions. By focusing modifications on the binding site sequences rather than the entire gene, the invention achieves precise control over GRF expression while maintaining the rest of the gene's natural function

Inventive Principle:

Principle #2Taking out (Extraction)

2Productivity

If foreign transgenes are introduced to overexpress GRF transcription factors, then GRF mRNA levels increase and plant growth is enhanced, but the plant contains foreign DNA that may have regulatory or safety concerns

Engineering Contradiction:

Improveplant growth and grain yieldVSAvoidforeign transgene presence

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent employs self-service by using the plant's own endogenous GRF genes as the source of overexpression. Rather than introducing foreign transgenes, the invention modifies the plant's native genes to increase their expression levels, allowing the plant to serve itself and eliminate the need for external genetic material

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent converts the natural miR396-mediated repression (which normally limits GRF expression) into a benefit by introducing mutations that prevent this repression. The harmful effect of miR396 binding is transformed into a positive outcome by designing binding site mutations that abolish or reduce this interaction, thereby increasing GRF mRNA stability and expression

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Productivity

If traditional breeding or transgenic methods are used to enhance grain size, then yield improvement may be achieved, but the process is time-consuming and requires complex regulatory approval

Engineering Contradiction:

Improvegrain yieldVSAvoidbreeding and regulatory approval time

Core Design Contradiction:

ProductivityVSLoss of time

Solution Approach 1:

The patent replaces traditional mechanical breeding methods (crossing, selection, and repeated backcrossing) with precise molecular editing technology. CRISPR-Cas9 or similar genome editing systems are used to directly introduce specific point mutations at the miR396 binding sites, achieving in one generation what would traditionally require multiple generations of breeding and selection

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent applies preliminary action by pre-designing and pre-testing the specific nucleotide mutations at the miR396 binding sites before implementation. The binding site sequences are analyzed in silico to predict mutation effects, and the most promising mutations are selected and then introduced into the genome, streamlining the development process

Inventive Principle:

Principle #10Preliminary action

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 solution results in increased levels of GRF mRNA, leading to enhanced plant growth and grain size, providing a method for producing transgene-free plants with improved phenotypic characteristics.

Implementation Method 1

A 2 bp substitution mutation in GS2 perturbs OsmiR396-directed regulation of GS2, resulting in large and heavy grains and increased grain yield

Methodology Applied

Scientific EffectBase substitution mutation:

Implementation Method 2

Introduce specific mutations or genomic modifications in the miR396 binding sites of GRF transcription factor genes using a CRISPR-associated effector protein and cytidine or adenosine deaminase

Methodology Applied

Scientific EffectCRISPR-associated base editing:

Data Source

PatentUS12545924B2Mutation of growth regulating factor family transcription factors for enhanced plant growth

Publication Date: 2026.02.10 PAIRWISE PLANTS SERVICES INC

AI summary

This invention relates to compositions and methods for modifying Growth Regulating Factor (GRF) family transcription factors in plants to produce plants having improved phenotypic characteristics including increased growth. The invention further relates to plants produced using the methods and compositions of the invention.