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Abstract [Objective] Tonoplast sugar transporters (TSTs or TMTs) are crucial sugar transport proteins in plant development. The study aims to investigate the role of this gene family in grape growth and development, to provide a foundation for understanding the function of TST genes. [Methods] A total of 13 TST genes were identified from the grape genome using homology analysis. Gene structures and encoded proteins were analyzed using bioinformatics tools. Utilizing the qRT-PCR technique, TST expression levels in different tissues during ‘Yinhong’ grape development were analyzed, and a correlation with soluble sugar contents in the grapes at different time points were studied. [Results] The TST genes was distributed across the six chromosomes and contained three segmental repetitions and three tandem repetition genes. It could be classified into three subfamilies, each with members sharing structural similarity. TST genes included ample cis regulatory elements related to phytohormone, light, and stress response. Protein family was composed of α-helices and irregular coils, and the protein model of each subfamily was similar. VvTST was expressed in various tissues, possessing spatiotemporal expression specificity. Correlation analysis found that the expression levels of four VvTSTs, including VIT _18s0001g12560, VIT _ 18s0122g00850, VIT_04s0023g01860, and VIT_03s0038g03940, exhibited similar trends with the accumulation of soluble sugars in the grape flesh. [Conclusion] VvTST may play a vital role in soluble sugar accumulation in grape flesh.

Estrogen receptor (ER) is overexpressed in approximately 2/3 of breast cancer patients’ lesions. Noninvasive detection of ER in vivo and dynamic monitoring of ER are crucial for individualized treatment decision-making. 16α-18F-17β-fluoroestradiol (18F-FES) positron emission tomography (PET) has been used in a variety of preclinical and clinical studies to detect ER expression. However, there is still a lack of technical specifications in China. This technical specification was jointly written by domestic experts who had experience of 18F-FES PET imaging and was formed through consultation based on their own experience and research progress in this field both domestically and internationally. This technical specification introduced the synthesis method and quality control requirements of 18F-FES, recommended its clinical application scenarios, and classified them. In addition, experts’ suggestions were provided throughout the entire process systemically and detailly, including pre-imaging preparation, imaging process, image analysis (normal biological distribution, determination of ER positive and negative, lesion detection, influencing factors, false negative and false positive, report requirements), and the limitations of this imaging technique were proposed. The future application prospects were also discussed. This specification aimed to promote the standardized application of 18F-FES PET in China, achieve repeatability and comparability, and provide important molecular imaging technical support for accurate diagnosis and treatment of breast cancer.

Background and purpose: Nasopharyngeal carcinoma is one of the most common head and neck malignancies in Southeast Asia. Radiotherapy combined with chemotherapy is the main treatment for patients with locally advanced nasopharyngeal carcinoma (LANPC), however, different patients have various levels of clinical benefit. Therefore, early and accurate evaluation of the prognosis of LANPC after radiotherapy and chemotherapy is of great significance for clinical treatment decision-making. This paper aimed to evaluate and compare the value of 18F-Fluorothymidine (FLT) and 18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging parameters in predicting the prognosis of patients with LANPC after radiotherapy and chemotherapy. Methods: Patients with LANPC who all received intensity-modulated radiation therapy (IMRT) and neoadjuvant chemotherapy (NACT) in Fudan University Shanghai Cancer Center from May 2012 to January 2015 were retrospectively selected. Clinical follow-up endpoint was progression-free survival (PFS), defined as the time from the beginning of treatment to tumor progression or death from any cause. The focus evaluation was based on the Response Evaluation Criteria in Solid Tumor 1.1 (RECIST 1.1). Pretreatment 18F-FLT and 18F-FDG PET/CT imaging were performed respectively. And the time interval between the two imaging was maintained within 1 week. The main parameters were measured, including maximal standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), proliferative tumor volume (PTV)/metabolic tumor volume (MTV), total lesion thymidine (TLT)/ total lesion glucose (TLG) and tumor heterogeneity index (HI). Spearman rank correlation coefficient was used to analyze the correlation between the above PET/CT parameters and patients with metastasis/recurrence of LANPC. Then, the best cut-off value was determined by the receiver operating characteristic (ROC) curve, and the predictive ability was evaluated by the ROC curve. PFS was evaluated by the Kaplan-Meier method and log-rank test. Results: Among the 24 patients, 6 had metastasis or recurrence. The median follow-up time was 74.51 months. Spearman rank correlation coefficient analysis showed that HI(T-FLT-70%SUVmax) was associated with metastasis or recurrence (P=0.04); ROC curve analysis showed that the sensitivity of HI(T-FLT-70%SUVmax) in predicting metastatic or recurrent nasopharyngeal carcinoma was 80.00%, and the specificity was 79.90% (P=0.043). Survival analysis showed that when HI(T-FLT-70%SUVmax)>0.828, the median PFS was 57.99 months, which was significantly shorter compared with patients with HI(T-FLT-70%SUVmax)0≤0.828 (P=0.014). Conclusion: HI based on 18F-FLT PET/CT may be useful for predicting the prognosis of patients with LANPC receiving radiotherapy and chemotherapy.

SUMMARY: Soybean is an important plant source of protein worldwide. Increasing demands for soybean can be met by improving the quality of its seed protein. In this study, GmCG‐1, which encodes the β‐conglycinin α′ subunit, was identified via combined genome‐wide association study and transcriptome analysis. We subsequently knocked down GmCG‐1 and its paralogues GmCG‐2 and GmCG‐3 with CRISPR‐Cas9 technology and generated two stable multigene knockdown mutants. As a result, the β‐conglycinin content decreased, whereas the 11S/7S ratio, total protein content and sulfur‐containing amino acid content significantly increased. Surprisingly, the globulin mutant exhibited salt tolerance in both the germination and seedling stages. Little is known about the relationship between seed protein composition and the salt stress response in soybean. Metabonomics and RNA‐seq analysis indicated that compared with the WT, the mutant was formed through a pathway that was more similar to that of active salicylic acid biosynthesis; however, the synthesis of cytokinin exhibited greater defects, which could lead to increased expression of plant dehydrin‐related salt tolerance proteins and cell membrane ion transporters. Population evolution analysis suggested that GmCG‐1, GmCG‐2, and GmCG‐3 were selected during soybean domestication. The soybean accessions harboring GmCG‐1Hap1 presented relatively high 11S/7S ratios and relatively high salt tolerance. In conclusion, knockdown of the β‐conglycinin α and α′ subunits can improve the nutritional quality of soybean seeds and increase the salt tolerance of soybean plants, providing a strategy for designing soybean varieties with high nutritional value and high salt tolerance. Significance Statement: CRISPR‐CAS9 generated soybean mutants of β‐conglycinin α and α′ subunits increases sulfur‐containing amino acids and protein contents, further enhances the salt tolerance, thus providing a new strategy for designing soybean varieties with both high nutritional value and high salt tolerance. [ABSTRACT FROM AUTHOR]

Soybean [Glycine max (L.) Merr.], as a globally commercialized crop, is an important source of protein and oil for both humans and livestock. With more frequent extreme weather disasters, abiotic stress has become one of the critical factors restricting soybean production. Proline (Pro) is a well-known substance in plants that responds to abiotic stress. To identify potential effector genes involved in soybean resistance to abiotic stress, we focused on the pyrroline-5-carboxylate dehydrogenase (P5CDH) which is a key enzyme in the degradation process of Pro. Through homologous sequence alignment, phylogenetic tree, and predicted expression, we chose GmP5CDH1 (Glyma.05G029200) for further research. Tissue-specific expression assay showed that GmP5CDH1 had higher expression levels in soybean seed and cotyledon development. Subcellular localization assay revealed that GmP5CDH1 was a nuclear-membrane-localized protein. As the result of the predicted cis-acting regulatory element indicates, the expression level of GmP5CDH1 was induced by low temperature, drought, salt stress, and ABA in soybean. Next, we constructed transgenic Arabidopsis overexpressing GmP5CDH1. The results showed that GmP5CDH1 also strongly responded to exogenous Pro, and overcame the toxicity of abiotic stress on plants by regulating the endogenous concentration of Pro. The interaction between GmP5CDH1 and GmSAM1 was validated through yeast two-hybrid, LUC fluorescence complementary, and BIFC. In conclusion, overexpression of a soybean pyrroline-5-carboxylate dehydrogenase GmP5CDH1 regulates the development of Arabidopsis thaliana by altering proline content dynamically under salt stress, especially improving the growth of plants under exogenous Pro. [ABSTRACT FROM AUTHOR]

Rhododendron, a globally popular ornamental flower, is nevertheless limited in our understanding of the mechanisms underlying its fragrance formation. Notably, terpenoids are the most prevalent volatile metabolite produced by plants. In this study, gas chromatography–mass spectrometry (GC–MS), liquid chromatography–mass spectrometry (LC–MS) and transcriptomics sequencing were conducted to analyze the synthesis mechanisms of terpenoid fragrance compounds of petals in fragrant R. fortunei Lindl. (YJ) and non-fragrant R. "Nova Zembla" (NW). The results identified that (-)-myrtenol, linalool, pinene, myrtenyl acetate, and terpineol were key floral aroma substances in YJ. Furthermore, an analysis of KEGG enrichment and differentially expressed genes (DEGs) revealed that the bud and decay stages exhibited the highest number of enriched DEGs among different aroma types, indicating these as critical stages for the synthesis of terpenoid floral compounds. In this study, a structural gene, denoted as RfFDPS, was identified as a negative regulatory gene for monoterpene accumulation and a positive regulatory gene for sesquiterpene accumulation in YJ. Utilizing subcellular localization technology, we determined that RfFDPS proteins are located in the cytoplasm. A functional analysis through transient expression and gene silencing of RfFDPS demonstrated its ability to regulate the accumulation of monoterpenes and sesquiterpenes. The overexpression of RfFDPS led to an increase in the expression of structural genes related to terpenoid synthesis, resulting in a decrease in monoterpenes and an increase in sesquiterpenes. Conversely, gene silencing had the opposite effect. In conclusion, RfFDPS plays a pivotal role in the synthesis and release of terpenoid volatile compounds in YJ petals, laying a solid theoretical foundation for the cultivation and enhancement of aromatic R. species. [ABSTRACT FROM AUTHOR]