Soybean hypocotyl elongation is regulated by a MYB33-SWEET11/21-GA2ox8c module involving long-distance sucrose transport.

The length of hypocotyl affects the height of soybean and lodging resistance, thus determining the final grain yield. However, research on soybean hypocotyl length is scarce, and the regulatory mechanisms are not fully understood. Here, we identified a module controlling the transport of sucrose, where sucrose acts as a messenger moved from cotyledon to hypocotyl, regulating hypocotyl elongation. This module comprises four key genes, namely MYB33, SWEET11, SWEET21 and GA2ox8c in soybean. In cotyledon, MYB33 is responsive to sucrose and promotes the expression of SWEET11 and SWEET21, thereby facilitating sucrose transport from the cotyledon to the hypocotyl. Subsequently, sucrose transported from the cotyledon up-regulates the expression of GA2ox8c in the hypocotyl, which ultimately affects the length of the hypocotyl. During the domestication and improvement of soybean, an allele of MYB33 with enhanced abilities to promote SWEET11 and SWEET21 has gradually become enriched in landraces and cultivated varieties, SWEET11 and SWEET21 exhibit high conservation and have undergone a strong purified selection and GA2ox8c is under a strong artificial selection. Our findings identify a new molecular pathway in controlling soybean hypocotyl elongation and provide new insights into the molecular mechanism of sugar transport in soybean.

Genome-wide analysis of Dof transcription factors and their response to cold stress in rice (Oryza sativa L.).

BACKGROUND: Rice (Oryza sativa L.) is a food crop for humans worldwide. However, temperature has an effect during the vegetative and reproductive stages. In high-latitude regions where rice is cultivated, cold stress is a major cause of yield loss and plant death. Research has identified a group of plant-specific transcription factors, DNA binding with one zinc fingers (DOFs), with a diverse range of functions, including stress signaling and stress response during plant growth. The aim of this study was to identify Dof genes in two rice subspecies, indica and japonica, and screen for Dof genes that may be involved in cold tolerance during plant growth. RESULTS: A total of 30 rice Dofs (OsDofs) were identified using bioinformatics and genome-wide analyses and phylogenetically analyzed. The 30 OsDOFs were classified into six subfamilies, and 24 motifs were identified based on protein sequence alignment. The chromosome locations of OsDofs were determined and nine gene duplication events were identified. A joint phylogenetic analysis was performed on DOF protein sequences obtained from four monocotyledon species to examine the evolutionary relationship of DOF proteins. Expression profiling of OsDofs from two japonica cultivars (Longdao5, which is cold-tolerant, and Longjing11, which is cold-sensitive) revealed that OsDof1 and OsDof19 are cold-inducible genes. We examined the seed setting rates in OsDof1- and OsDof19-overexpression and RNAi lines and found that OsDof1 showed a response to cold stress. CONCLUSIONS: Our investigation identified OsDof1 as a potential target for genetic breeding of rice with enhanced cold tolerance.

Genetic and lipidomic analyses reveal the key role of lipid metabolism for cold tolerance in maize.

Lipid remodeling is crucial for cold tolerance in plants. However, the precise alternations of lipidomics during cold responses remain elusive, especially in maize (Zea mays L.). In addition, the key genes responsible for cold tolerance in maize lipid metabolism have not been identified. Here, we integrate lipidomic, transcriptomic, and genetic analysis to determine the profile of lipid remodeling caused by cold stress. We find that the homeostasis of cellular lipid metabolism is essential for maintaining cold tolerance of maize. Also, we detect 210 lipid species belonging to 13 major classes, covering phospholipids, glycerides, glycolipids, and free fatty acids. Various lipid metabolites undergo specific and selective alterations in response to cold stress, especially mono-/di-unsaturated lysophosphatidic acid, lysophosphatidylcholine, phosphatidylcholine, and phosphatidylinositol, as well as polyunsaturated phosphatidic acid, monogalactosyldiacylglycerol, diacylglycerol, and triacylglycerol. In addition, we identify a subset of key enzymes, including ketoacyl-acyl-carrier protein synthase II (KAS II), acyl-carrier protein 2 (ACP2), male sterility33 (Ms33), and stearoyl-acyl-carrier protein desaturase 2 (SAD2) involved in glycerolipid biosynthetic pathways are positive regulators of maize cold tolerance. These results reveal a comprehensive lipidomic profile during the cold response of maize and provide genetic resources for enhancing cold tolerance in crops.

Effects of concentration-dependent graphene on maize seedling development and soil nutrients.

The long-term use of chemical fertilizers to maintain agricultural production has had various harmful effects on farmland and has greatly impacted agriculture's sustainable expansion. Graphene, a unique and effective nanomaterial, is used in plant-soil applications to improve plant nutrient uptake, reduce chemical fertilizer pollution by relieving inadequate soil nutrient conditions and enhance soil absorption of nutrient components. We investigated the effects of graphene amendment on nutrient content, maize growth, and soil physicochemical parameters. In each treatment, 5 graphene concentration gradients (0, 25, 50, 100, and 150 g kg-1) were applied in 2 different types (single-layer and few-layers, SL and FL). Soil aggregates, soil accessible nutrients, soil enzyme activity, plant nutrients, plant height, stem diameter, dry weight, and fresh weight were all measured throughout the maize growth to the V3 stage. Compared to the control (0 g kg-1), we found that graphene increased the percentage of large agglomerates (0.25-10 mm) in the soil and significantly increased the geometric mean diameter (GMD) and mean weight diameter (MWD) values of > 0.25 mm water-stable agglomerates as the increase of concentration. Soil available nutrient content (AN, AP, and AK) increased, peaking at 150 g kg-1. Graphene boosted nutrient absorption by maize plants, and aboveground total nitrogen (TN), total phosphorus (TP), and total potassium (TK) contents rose with the increasing application, which raised aboveground fresh weight, dry weight, plant height, and stalk thickness. The findings above confirmed our prediction that adding graphene to the soil may improve maize plant biomass by enhancing soil fertility and improving the soil environment. Given the higher manufacturing cost of single-layer graphene and the greater effect of few-layer graphene on soil and maize plants at the same concentration, single-layer graphene and few-layer graphene at a concentration of 50 g kg-1 were the optimal application rates.

Foliar spraying of exogenous uniconazole (S3307) at the flowering stage as an effective method to resist low-temperature stress on mung bean [Vigna radiata (L.) Wilczek].

Low temperature is one of the major constraints on agricultural productivity worldwide and is likely to further increase. Several adaptations and mitigation strategies are required to cope with low-temperature stress. Uniconazole (S3307) could play a significant role in the alleviation of abiotic stress in plants. In this study, the effects of S3307 on the reactive oxygen species (ROS) and antioxidant metabolism were studied in the leaves of mung bean [Vigna radiata (L.) Wilczek]. The experimental results showed that the low-temperature induced accumulation of superoxide anion (O2-) production rate, and malonaldehyde (MDA) contents. Increased proline content and enzymatic antioxidants, including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), were found to alleviate oxidative damage under low temperatures. While, S3307 could reduce O2- production rate and MDA contents and increase the activities of SOD, POD, and CAT, slowed the decrease in ascorbic acid (AsA), dehydroascorbic acid (DHA), glutathione (GSH), and oxidized glutathione (GSSG), and promoted increase in soluble sugars (SS), soluble proteins (SP), and proline (Pro) content under low-temperature. At the same time, low temperature leads to lower 100 grain weight and number of grains per plant, which eventually causes yield reduction decreased. Foliar spraying of S3307 could alleviate the yield loss caused by low temperature, and the increase of S3307 treatment was 5.1%-12.5% and 6.3%-32.9% for the two varieties, respectively, compared with CK. In summary, exogenous S3307 pretreatment enhances plant tolerance to low-temperature by improving the antioxidant enzyme activities, increased non-enzymatic antioxidants content, and decreased O2- production rate and MDA contents and inducing alterations in endogenous S3307, and reduce the decrease in mung bean yield.

Physiological response of soybean leaves to uniconazole under waterlogging stress at R1 stage.

Waterlogging is a major limiting factor in global crop production and seriously endangers growth and yield improvement in low-lying, rainfed regions. Soybean is an important economic crop affected by waterlogging stress. The current study investigates the effects of waterlogging stress on the leaf physiology and yield of two soybean varieties (Kenfeng 14, waterlogging-tolerant and Kenfeng 16, waterlogging-sensitive) and the mitigation effect of uniconazole (S3307) in promoting growth and productivity under waterlogging conditions. The results showed that waterlogging stress increased antioxidant enzyme activity and decreased the contents of non-enzymatic antioxidants such as AsA and GSH. Furthermore, the content of MDA and H2O2 increased significantly, indicating oxidative stress and O2-· production rate also improved, and the increase in the waterlogging-sensitive variety Kenfeng 16 was greater than that of the waterlogging-tolerant variety Kenfeng 14. Spraying S3307, however, increased the activities of antioxidants such as SOD, POD, CAT, and APX. GR, MDHAR, and DHAR increased the content of non-enzymatic antioxidants, effectively inhibited the increase of MDA, H2O2 content, and O2-· production rate, and alleviated the loss of yield factors caused by waterlogging stress. The waterlogging-tolerant variety Kenfeng 14 recovered better than the waterlogging-sensitive variety Kenfeng 16. In summary, S3307 ameliorated the effects of waterlogging stress on the physiological characteristics of soybean leaves and improved yield as a result of improved antioxidant defense mechanisms that impeded lipid peroxidation. Thus, S3307 could decelerate the damages caused by waterlogging stress to some extent.

circFLNA promotes glioblastoma proliferation and invasion by negatively regulating miR­199­3p expression.

Glioblastoma (GBM) is one of the most common and malignant types of primary cancer in the central nervous system; however, the clinical outcomes of patients with GBM remain poor. Circular RNAs (circRNAs) have been revealed to serve important roles in diverse biological processes, such as regulating cell proliferation, epithelial­mesenchymal transition and tumor development. However, the underlying biological function of circRNA filamin A (circFLNA) and its potential role in GBM remain to be determined. The present study aimed to identify differentially expressed circRNAs in GBM. Reverse transcription­quantitative PCR was used to analyze the expression levels of circFLNA. The results demonstrated that the expression levels of circFLNA were significantly upregulated in clinical GBM samples and GBM cells compared with adjacent healthy brain tissues and normal human astrocytes, respectively. The results of the Cell Counting Kit­8 and Transwell assays revealed that circFLNA knockdown significantly inhibited the proliferative and invasive abilities of GBM cell lines. Moreover, high circFLNA expression levels were associated with a worse prognosis in GBM. MicroRNA (miR)­199­3p was subsequently predicted to be target of circFLNA. The inhibitory effect of miR­199­3p on cell proliferation and invasion was partially reversed following circFLNA knockdown. In conclusion, the findings of the present study identified novel roles for circFLNA in GBM and indicated that the circFLNA/miR­199­3p signaling axis may serve an important role in GBM progression. Therefore, circFLNA may represent a novel target for the diagnosis and treatment of GBM.

The Soybean Gene J Contributes to Salt Stress Tolerance by Up-Regulating Salt-Responsive Genes.

Soybean [Glycine max (L.) Merr.] is an important crop for oil and protein resources worldwide, and its farming is impacted by increasing soil salinity levels. In Arabidopsis the gene EARLY FLOWERING 3 (ELF3), increased salt tolerance by suppressing salt stress response pathways. J is the ortholog of AtELF3 in soybean, and loss-of-function J-alleles greatly prolong soybean maturity and enhance grain yield. The exact role of J in abiotic stress response in soybean, however, remains unclear. In this study, we showed that J expression was induced by NaCl treatment and that the J protein was located in the nucleus. Compared to NIL-J, tolerance to NaCl was significantly lower in the NIL-j mutant. We also demonstrated that overexpression of J increased NaCl tolerance in transgenic soybean hairy roots. J positively regulated expression of downstream salt stress response genes, including GmWRKY12, GmWRKY27, GmWRKY54, GmNAC, and GmSIN1. Our study disclosed a mechanism in soybean for regulation of the salt stress response. Manipulation of these genes should facilitate improvements in salt tolerance in soybean.

[Spinal dural arteriovenous fistulae associated with perimedullary arteriovenous fistulae: imaging characteristics and surgical treatment].

OBJECTIVE: To enhance the clinical doctors' cognizance of atypical spinal dural arteriovenous fistulae (SDAVFs) associated with perimedullary anteriovenous fistulae (PMAVFs). METHODS: The clinical imaging and surgical therapy of 3 patients with PMAVFs were analyzed retrospectively. RESULTS: The clinical presentations of the 3 patients were not significantly different from those of typical SDAVFs. They were verified by repeated spinal angiography that the anterior spinal artery (ASA) is supplied to the drainage-vein. The 3 patients were treated surgically. First two operations were performed to eliminate the supply of ASA and dural branch, then the supply of the dural branch was amputated, and finally both the ASA and dural branch supplies were excised successfully. Clinical symptoms of the 3 patients were improved after treatment. CONCLUSIONS: It is necessary to perform thorough spinal angiography in patients with SDAVFs to exclude another fistula. The key point in the treatment of such patients is successfully to terminate both the spinal feeder and dural branch feeder.