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Biology subjects

Nguyen, C. X.

Publications and source records attributed to Nguyen, C. X..

2 recordsLinked to original sources

Application of AI-Designed OpenCRISPR-1 for Highly Efficient Gene Editing in Soybean and Nicotiana benthamiana

The widespread application of CRISPR/Cas genome editing for commercial crop improvement is currently hindered by a complex and restrictive intellectual property (IP) landscape. The recent development of OpenCRISPR-1, a fully AI-designed and open-source Cas9-like nuclease, provides a promising, IP-unencumbered alternative; however, its efficacy in dicotyledonous plants remains largely uncharacterized. Here, we report the successful adaptation of the OpenCRISPR-1 system for highly efficient targeted mutagenesis in dicots. We constructed a plant-optimized binary vector (pBSE-OpenCRISPR-1) and validated its editing capability across two species. In soybean (Glycine max), targeting the GmFAD2-1B gene via an Agrobacterium rhizogenes-mediated hairy root transformation system yielded a robust mutation rate of approximately 50%. In Nicotiana benthamiana, stable Agrobacterium-mediated transformation targeting the phytoene desaturase homologs (NbPDSa/b) achieved a 75% editing efficiency in T0 lines, with up to 13.8% of events displaying complete homozygous or biallelic mutations and the corresponding visible albino phenotypes. Deep amplicon and Sanger sequencing revealed a characteristic mutation profile dominated by 1-bp insertions and small deletions occurring two to three nucleotides upstream of the PAM. These results demonstrate that the AI-designed OpenCRISPR-1 system is a highly active and versatile nuclease for dicot genome engineering, offering a powerful, commercially unencumbered tool to accelerate global crop trait improvement.

plant biology↗

Hydrogen sulfide-mediated vasodilation requires heme oxygenase-derived carbon monoxide

BackgroundHydrogen sulfide (H2S) is an important endothelial-derived vasodilator, but the signaling mechanism remains incompletely understood. We previously demonstrated that H2S-mediated vasodilation requires transient receptor potential vanilloid type 4 (TRPV4) channels. Because H2S has been reported to enhance heme oxygenase (HO) activity and HO-derived carbon monoxide (CO) regulates endothelial signaling, we hypothesized that H2S-mediated vasodilation requires HO-2-derived CO. MethodsPressure myography was performed in isolated rat mesenteric arteries to determine the contribution of HO, TRPV4, eBK, and SK/IK channels to H2S-mediated vasodilation. HO-2 sulfhydration was assessed using a maleimide assay, and spatial association among HO-2 and TRPV4 was examined using proximity ligation assays in human aortic endothelial cells. ResultsH2S Selicited concentration-dependent vasodilation that was abolished by HO inhibition. Repletion of CO restored H2S-mediated vasodilation in the presence of HO inhibition. CO-mediated vasodilation was abolished by TRPV4 and SK/IK inhibition but was unaffected by eBK inhibition. H2S increased HO-2 sulfhydration and enhanced HO activity. In endothelial cells, HO-2 and TRPV4 exhibited close spatial association. ConclusionsThese findings support a model in which H2S stimulates HO-2-derived CO production, leading to TRPV4-dependent endothelial signaling, SK/IK activation, and vasodilation. Together, the data support the existence of an endothelial HO-2/TRPV4/SK/IK signaling domain that contributes to H2S-mediated vascular reactivity.

physiology↗