CARBON Newsletter (17 July 2026) - Your Latest News About CRISPR in AgroBio

Top picks

• Suppressor screening identified OsSnRK1β1A as a regulator that boosts rice grain number by restricting nuclear localization of OsSnRK1α1 and suppressing energy catabolism, while OsOTUB1 keeps it in check via competitive inhibition and K63-linked deubiquitination that triggers its degradation. This OsOTUB1-OsSnRK1β1A module reallocates carbon, nitrogen, and lipid metabolism toward reproductive development, and CRISPR-Cas9 promoter editing (targeting the CAREOSREP1 and CCAAT-box elements) to upregulate OsSnRK1β1A increased yield without harming plant architecture – offering a practical route to higher-yield rice.
• Tropic has acquired banana propagation company Rahan Meristem to accelerate global deployment of its gene-edited banana varieties. The deal integrates variety development, propagation and distribution, supporting commercial rollout of bananas with traits including disease resistance, reduced browning, extended shelf life, higher yields and resilience to threats such as Panama disease TR4. The acquisition strengthens Tropic’s capacity to scale production and grower adoption worldwide.

Technical advances

• Researchers present a modular Golden Gate toolkit for the diatom Thalassiosira pseudonana that delivers fluorescent protein tagging, dual tagging, CRISPR-Cas9 editing, and scarless endogenous tagging from a single conjugated episome. Using it, the authors knocked out DPC1 while GFP-tagging Rubisco's rbcS subunit, showing no major pyrenoid defect, and endogenously tagged the bestrophin-like protein BST2, confirming its pyrenoid localization and CO2-responsive expression – supporting a role in carbon fixation.
• Researchers have achieved conjugative DNA transfer into Nostoc azollae, the obligate nitrogen-fixing cyanobiont of Azolla ferns, both in isolated culture and in planta – the latter enabled by cytokinin treatment that made fern shoot apexes accessible to conjugation. Using triparental mating and promoters including those from a CRISPR-associated transposon (CAST) system, they achieved heterologous gene expression in two developmental stages of the symbiont, including the vertically transmitted stem-cell population. This establishes a genetic toolkit for studying cyanobacterial endosymbiosis, with potential relevance to other symbiotic systems.

Disease and stress control

• Using CRISPR-Cas9 knockout and overexpression lines, researchers show that OsHIPP36, a plasma membrane-localized metallochaperone induced by arsenite stress, negatively regulates rice arsenite tolerance – its loss boosts tolerance by trapping arsenite in roots and limiting shoot translocation. This is the first evidence linking HIPP proteins to arsenite handling in rice, offering a potential target for reducing grain arsenic accumulation.
• CRISPR-Cas9 knockout studies reveal that GmWRKY20 and its interacting partner GmbZIP9 form a synergistic transcriptional module that drives soybean drought tolerance by activating GmANKTM21, boosting antioxidant defenses beyond what either gene achieves alone. The GmWRKY20-GmbZIP9 heterodimer binds the GmANKTM21 promoter directly, offering a promising target for breeding drought-resilient soybean varieties.
• Using CRISPR-Cas9 mutants, researchers show that ethylene drives adventitious root formation in waterlogged cucumber through CsWRKY41, which activates the ABA receptor gene CsPYL4 while repressing the phosphatase gene CsPP2C24. This shift boosts CsPrx2 expression and H2O2 accumulation, promoting root growth – revealing an ethylene–ABA crosstalk module (CsWRKY41–CsPYL4–CsPP2C24) that helps cucumber cope with waterlogging stress.
• A meta-synthesis argues that resilience to combined climate stresses (drought, heat, salinity) emerges from an "epigenetic toolkit" – RNA-directed DNA methylation and chromatin remodeling – working alongside rhizosphere and endosphere microbiota that prime host stress memory. While CRISPR-mediated epigenome editing and microbiome engineering show promise for breeding "primed" crops, field-scale stability remains context-dependent, pointing to a needed shift from single-trait breeding toward multi-scale regulatory strategies.
• Using a full set of CRISPR-Cas9 mutants, researchers dissected the three rice OsJAR genes and found they've split up jasmonic acid signaling duties. OsJAR1 and OsJAR2 redundantly sustain basal growth, while OsJAR1 alone drives herbivore defense against the brown planthopper via a MYC2-bHLH6 feedback loop, and OsJAR2 alone supports spikelet development during inflorescence differentiation. OsJAR3 appears largely nonfunctional. The work shows how a single hormone pathway achieves distinct outputs through gene-specific specialization.
• A new study shows that the phytoplasma effector SJP3 suppresses jujube's jasmonic acid defenses by binding and stabilizing ZjWRKY40, which in turn drives expression of the JA suppressors ZjTIFY3B and ZjTIFY5A. Since exogenous methyl jasmonate reduced both phytoplasma titre and SJP3 expression, the SJP3–ZjWRKY40–ZjTIFY3B/5A axis offers a promising gene target for CRISPR-Cas-based breeding of witches'-broom disease resistance.
• Using overexpression and CRISPR-Cas9 knockout lines, researchers identify LaNAC72, the lupin homolog of wild soybean's GsNAC019, as a key driver of alkaline tolerance that improves root architecture and interacts with LaNAC2 to form a stress-response module. Mechanistically, LaNAC72 directly binds the LaFD promoter and upregulates IAA and ABA pathway genes (LaIAA8/16/26, LaFD, LaLRX5, LaABI5 – in vivo activation strengthened under stress) to reinforce alkaline resilience, offering a target for engineering better-adapted lupin crops.
• Overexpression and CRISPR-Cas9 knockout of GmSNAT1, a melatonin biosynthesis gene, show it drives soybean cold tolerance – a phenotype rescued by exogenous melatonin – by activating calcium signaling, coordinating auxin/ABA/ethylene crosstalk, boosting antioxidant defenses, and stabilizing photosynthesis. GmSNAT1 also physically interacts with the receptor GmPSYR1, linking melatonin signaling to root development and redox balance, and marking the pathway as a promising target for breeding cold-tolerant soybean.

Agronomic traits

• CRISPR-Cas9 editing, overexpression, and RNAi in kumquat identify ChSCL9, a GRAS transcription factor, as a negative regulator of citric acid accumulation that represses the vacuolar acidification genes ChPH4 and ChPH5. Mapped via bulked segregant analysis of a high- x low-acid F1 population, ChSCL9 offers a key target for breeding citrus with improved flavor.
• A new study identifies GhMYS1, a MYB transcription factor activated by GhHOX3, as a key brake on secondary cell wall synthesis in cotton fibers. By repressing GhCESA4 and GhCESA8, GhMYS1 delays wall thickening long enough for fibers to elongate properly; knocking it out via CRISPR shortened fibers and thickened walls prematurely. The GhHOX3-GhMYS1-GhCESA4/8 module offers a promising genetic target for breeding better cotton fiber quality.
• Using CRISPR-Cas9 editing and prime editing, researchers show that the rice cleistogamous mutant ld results from loss of miR172b (not miR806a), which normally represses the AP2-like gene SNB during lodicule development. Derepressed SNB alone was sufficient to reproduce the vestigial-lodicule, closed-flower phenotype, positioning the miR172b–SNB module – and the agronomically neutral ld allele – as a valuable tool for breeding cleistogamous rice varieties that limit transgene escape.
• Genome-wide analysis in broccoli identified BoSAUR21-like as consistently downregulated during postharvest senescence, and a T-DNA insertion mutant of its Arabidopsis homolog AtSAUR21 showed accelerated leaf senescence, early bolting, and chlorophyll loss – pointing to a conserved anti-senescence role. The authors propose BoSAUR21-like as a candidate for CRISPR-Cas9 knockout and overexpression studies to extend broccoli's postharvest shelf life.
• CRISPR-Cas9 knockouts of CsSPX2 in cucumber reveal it as a phosphate sensor linking Pi homeostasis to lateral root development: loss of CsSPX2 causes phosphate overaccumulation, excess lignin deposition, thickened xylem-pole-pericycle cell walls, and blunted auxin responsiveness at lateral root initiation sites. Since lignin inhibitors or auxin partially rescued the defects, CsSPX2 emerges as a promising genetic target for breeding phosphate-efficient crops.
• CRISPR-Cas9 knockout of StCYP90C1, a brassinosteroid biosynthesis gene identified at the ap locus, reproduced the abnormal-architecture phenotype (dark-green curled leaves, short internodes, dwarfism) seen in natural mutants, confirming its role via reduced 6-deoxocathasterone and cathasterone levels. Two promoter variants lowering StCYP90C1 expression underlie the defect, marking this a deleterious locus that breeders should exclude when developing potato inbred lines.

Industry

• Phytoform will use its AI-guided genome editing platform to develop next-generation maize traits with Beck’s and RAGT by optimising native gene regulation to improve plant architecture, yield and productivity. The collaboration combines AI-driven trait design with elite breeding programmes for major global markets. The approach fine-tunes endogenous gene expression without introducing foreign DNA, potentially easing regulatory approval in some jurisdictions.

Screening

• A genome-wide CRISPR-Cas9 screen in the marine diatom Phaeodactylum tricornutum identified genes essential for survival under fluctuating light, revealing mechanisms underpinning photosynthetic adaptation. The study showed that the red lineage-specific protein STROBE1 enhances cyclic electron flow by promoting proton gradient formation across thylakoid membranes. The mutant library provides a powerful resource for uncovering novel gene functions in ecologically important diatoms.

Detection

• Researchers have developed Cas14P, a PCR assay using CRISPR-Cas14a as a detection reporter, to monitor genetically modified maize such as Bt11. The assay combines PCR amplification with Cas14a ribonucleoprotein signal reporting, achieving high sensitivity (0.064 ng/µL DNA, 1% GM content) and reliably distinguishing GM from non-GM maize. It offers a practical tool for regulatory oversight of GM crop cultivation.

Reviews

• Genetic technologies to enhance crop nutritional value under climate change. This review examines how CRISPR-Cas genome editing, combined with metabolic engineering and other technologies, could achieve crop biofortification to combat hidden hunger alongside enhanced yield and climate resilience.
• Tuning Tomato Immunity: Integrating Signaling Networks, Epigenetic Regulation, and Rhizosphere Microbiomes for Durable Resistance. This review examines recent advances in tomato disease resistance, highlighting immune signalling, epigenetic regulation, microbiome interactions and emerging strategies, including CRISPR-Cas9 and artificial microRNAs, to develop durable resistance and improve breeding.
• Molecular Intricacies of Modulating Seed Dormancy through CRISPR/Cas9 Technology. This review synthesizes current knowledge on the molecular and genetic mechanisms controlling seed maturation, dormancy acquisition and germination, with particular emphasis on emerging CRISPR-based strategies.
• Breeding drought-tolerant crops for sustainable agriculture. This review focuses on CRISPR-Cas genome editing and other technologies as key components of integrated breeding strategies for developing drought-tolerant crops, emphasising their combination with omics, speed breeding and other advanced technologies to accelerate the development of climate-resilient, high-yielding varieties.