Article information
Article title: A Gγ protein regulates alkaline sensitivity in crops
Journal: Science
Date of Publication: March 24, 2023
Main content: Qi Xie's team from the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences, the team of Feifei Yu of China Agricultural University and the team of Yidan Ouyang of Huazhong Agricultural University cooperated with 8 scientific research institutions jointly published an article of A Gγprotein regulates alkaline sensitivity in crops in the Science journal. This study discovered an important saline-alkali tolerance regulatory gene Alkali tolerance 1(AT1), which can significantly improve the saline-alkali tolerance of various crops, and revealed the molecular mechanism of AT1 participating in the alkali stress response by regulating the level of reactive oxygen species (ROS) in cells.
Article link: https://www.science.org/doi/10.1126/science.ade8416
Using TransGen products:
TransScript® II Reverse Transcriptase[M-MLV,RNaseH-]（High Temperature RT）(AH101)
TransStart® Green qPCR SuperMix UDG (AQ111)
INTRODUCTION
According to the Food and Agriculture Organization (FAO), there are currently >1 billion ha of land affected by salt. Among these, ~60% are classified as sodic soil areas. These have high pH and are dominated by sodium bicarbonate (NaHCO3) and sodium carbonate (Na2CO3). The effects of global warming and a lack of fresh water will lead to >50% of arable land becoming affected by salt by 2050, thus severely affecting the world’s food security. Identifying and/or engineering sodic-tolerant crops is imperative to solve this challenge. Although salinity tolerance has been studied extensively, alkalinity tolerance in plants has not been studied in depth.
RATIONALE
Sorghum originates from Africa, where it can grow in harsh environments. As a result, sorghum has evolved greater tolerance to adapt to multiple abiotic stresses compared with other crops. Some sorghum varieties can survive in sodic soil with a pH as high as 10.0. A genome-wide association study (GWAS) analysis was performed with a large sorghum association panel consisting of 352 representative sorghum accessions. They detected a major locus, Alkaline tolerance 1 (AT1), linked to alkaline tolerance. They found that AT1, encoding an atypical G protein γ subunit (a homolog to rice GS3), contributes to alkaline sensitivity by modulating the efflux of hydrogen peroxide (H2O2) under environmental stress.
RESULTS
On the basis of the results of the GWAS analysis, they sequenced the cDNA regions of SbAT1 (Sorghum bicolor AT1) in 37 sorghum accessions with different degrees of alkaline sensitivity. Two typical haplotypes (Hap1 and Hap2) of SbAT1 were identified according to the five leading variant sites associated with sorghum alkali sensitivity. Hap1 encodes an intact SbAT1. A frame shift mutation (from “G” to “GGTGGC”) within Hap2 results in a premature stop codon probably encoding a truncated protein with only 136 amino acids at the N terminus (named Sbat1).
To confirm the function of the AT1 locus, they generated a pair of near-isogenic lines (NILs) with two AT1 haplotypes to assess the allelic effect of AT1 on sorghum tolerance to alkali. They found that the Sbat1 allele (Hap2), encoding a truncated form of SbAT1, increased plant alkaline sensitivity compared with wild-type full-length SbAT1 (Hap1). Overexpression of AT1/GS3 reduced alkaline tolerance in sorghum and rice, and overexpression of the C-terminal truncated AT1/GS3 showed a more severe alkaline sensitive response. This was confirmed in millet and rice, which suggests that AT1/GS3 functions negatively in plant alkali tolerance. By contrast, knockout (ko) of AT1/GS3 increased tolerance to alkaline stress in sorghum, millet, rice, and maize, which indicates a conserved pathway in monocot crops.
By immunoprecipitation in combination with mass spectrometry (IP-MS), they found that AT1/GS3 interacts with aquaporin PIP2s that are involved in reactive oxygen species (ROS) homeostasis. Genetic analysis showed that OsPIP2;1ko/2;2ko had lower alkaline tolerance than their wild-type control. The redox probe Cyto-roGFP2-Orp1 sensing H2O2 in the cytoplasm was applied. The results showed that, upon alkaline treatment, the relative H2O2 level increased in OsPIP2;1ko/2;2ko compared with wild-type plants. These results suggested that the phosphorylation of aquaporins could modulate the efflux of H2O2. Gγ negatively regulates the phosphorylation of PIP2;1, leading to elevated ROS levels in plants under alkaline stress. To assess the application of the AT1/GS3 gene for crop production, field tests were carried out. They found that the nonfunctional mutant, either obtained from natural varieties or generated by gene editing in several monocots, including sorghum, millet, rice, and maize, can improve the field performance of crops in terms of biomass or grain production when cultivated on sodic lands.
CONCLUSION
They concluded that SbAT1 encodes an atypical G protein γ subunit and inhibits the phosphorylation of aquaporins that may be used as H2O2 exporters under alkaline stress. With this knowledge, genetically engineered crops with knockouts of AT1 homologs or use of natural nonfunctional alleles could greatly improve crop yield in sodic lands. This may contribute to maximizing the use of global sodic lands to ensure food security.
Genetic modification of AT1 enhances alkaline stress tolerance.
TransGen Product Support
High-quality reagents are a powerful tool for scientific research. TransScript® II Reverse Transcriptase[M-MLV, RNaseH-] (AH101) and TransStart® Green qPCR SuperMix UDG (AQ111) contributed to this study.
TransScript® II Reverse Transcriptase[M-MLV, RNaseH-] (AH101)
Features
• High thermal stability: the reaction temperature is 42℃-55℃.
• High sensitivity, specificity, and processivity ability.
• No RNase H activity, avoiding the degradation of the template RNA in the DNA/RNA hybrid during the first-strand cDNA synthesis reaction, thereby ensuring the amount and length of the first-strand cDNA synthesis.
• cDNA up to 15 kb.
TransStart® Green qPCR SuperMix UDG (AQ111)
Features
• TransStart® Taq DNA Polymerase, hot start with double blocking technique, improves sensitivity, enhances specificity and generates more accurate data.
• UDG enzyme and dUTP effectively prevent cross-contamination of PCR products, and the data is accurate.
•Double cation buffer enhances specificity, reduces primer-dimer formation and ensures the accuracy of the results.
•Passive Reference Dye suitable for different instruments (adjustment of tube-to-tube differences caused by pipetting errors), and the data is accurate.
TransGen products have once again been published in the Science journal, which proves customer's recognition of the quality and strength of the TransGen products, and also perfectly interprets the principle of " Quality is the highest priority. To serve the customers with superior quality and service. " that the TransGen has always adhered to. TransGen has always been on the road of helping scientific research, and hopes to work side by side with more scientific researchers in the future and continue to help scientific research with more and better products.
Some articles published using the TransScript® II Reverse Transcriptase [M-MLV, RNaseH-] (High Temperature RT) (AH101):
• Zhang H L, Yu F F, Xie P, et al. A Gγ protein regulates alkaline sensitivity in crops [J]. Science, 2023.
Some articles published using the TransStart® Green qPCR SuperMix UDG (AQ111):
• Zhang H L, Yu F F, Xie P, et al. A Gγ protein regulates alkaline sensitivity in crops [J]. Science, 2023.
• Zhang Y, Gao Y, Wang H L, et al. Verticillium dahliae secretory effector PevD1 induces leaf senescence by promoting ORE1-mediated ethylene biosynthesis[J]. Molecular plant, 2021.
• Zhang Y, Gao Y, Liang Y, et al. Verticillium dahliae PevD1, an Alt a 1-like protein, targets cotton PR5-like protein and promotes fungal infection[J]. Journal of experimental botany, 2019.
