Heat-inducible genome editing for sustainable crop yields and plant protection under heat stress

Overview

This research targets a central regulator of plant immunity, Calmodulin-binding transcription activator 3 (CAMTA3), to address a critical agricultural problem: crops lose their basal immune defenses at warm temperatures, leading to increased disease and yield loss. The proposed approach uses CRISPR/Cas9-based promoter editing in soybean to modify a cis-regulatory element bound by CAMTA3, with expression controlled by a heat-shock protein promoter (such as HSP70). This means the genetic modification activates only when plants are exposed to elevated temperatures. The goal is soybean lines that maintain robust pathogen defense while sustaining normal growth and yield under heat stress and other abiotic challenges such as drought, flooding, chilling, freezing, and salinity.

Technical specifications

Core scientific basis:

• CAMTA3 normally suppresses defense genes at warm temperatures; mutating it removes this suppression
• Loss of CAMTA3 function causes autoimmune-like high defense responses with stunted growth at normal temperatures, but at high temperatures growth penalties disappear while elevated defense is retained
• The growth-defense trade-off is therefore not deployed under heat stress

Editing strategy:

• CRISPR/Cas9-mediated editing of a CAMTA3-bound cis-regulatory element in the soybean genome
• Heat-shock protein promoter (e.g., HSP70) drives expression of the editing machinery so that modification occurs only upon heat exposure
• Designed to preserve normal growth under ambient conditions while enabling stress-responsive defense activation

Target outcomes:

• Enhanced tolerance to both biotic stresses (pathogen infection) and abiotic stresses (heat, drought, flooding, chilling, freezing, salinity)
• Maintenance or increase of crop yields under combined stress conditions

Technology readiness level

The research is at an early to mid stage of development. The scientific foundation is established through prior studies showing that CAMTA3 mutations decouple growth-defense trade-offs at high temperatures and that artificially activating defense under heat maintains normal growth. Future validation work will apply CRISPR/Cas9 promoter editing in soybean, with the editing system placed under a heat-shock protein promoter to achieve temperature-inducible modification. This represents a transition from validated biological mechanism toward applied genome editing in a major crop species, with further testing required to confirm editing efficiency, stress tolerance, and yield performance under field conditions.