Metabolome genome-wide association study provides biochemical and genetic insights into natural variation of primary metabolites in sesame.

Plants' primary metabolites are of great importance from the survival and nutritional perspectives. However, the genetic bases underlying the profiles of primary metabolites in oilseed crops remain largely unclear. As one of the main oilseed crops, sesame (Sesamum indicum L.) is a potential model plant for investigating oil metabolism in plants. Therefore, the objective of this study is to disclose the genetic variants associated with variation in the content of primary metabolites in sesame. We performed a comprehensive metabolomics analysis of primary metabolites in 412 diverse sesame accessions using gas chromatography-mass spectrometry and identified a total of 45 metabolites, including fatty acids, monoacylglycerols (MAGs), and amino acids. Genome-wide association study unveiled 433 significant single-nucleotide polymorphism loci associated with variation in primary metabolite contents in sesame. By integrating diverse genomic analyses, we identified 10 key candidate causative genes of variation in MAG, fatty acid, asparagine, and sucrose contents. Among them, SiDSEL was significantly associated with multiple traits. SiCAC3 and SiKASI were strongly associated with variation in oleic acid and linoleic acid contents. Overexpression of SiCAC3, SiKASI, SiLTPI.25, and SiLTPI.26 in transgenic Arabidopsis and Saccharomyces cerevisiae revealed that SiCAC3 is a potential target gene for improvement of unsaturated fatty acid levels in crops. Furthermore, we found that it may be possible to breed several quality traits in sesame simultaneously. Our results provide valuable genetic resources for improving sesame seed quality and our understanding of oilseed crops' primary metabolism.

Fine mapping of qAHPS07 and functional studies of AhRUVBL2 controlling pod size in peanut (Arachis hypogaea L.).

Cultivated peanut (Arachis hypogaea L.) is an important oil and cash crop. Pod size is one of the major traits determining yield and commodity characteristic of peanut. Fine mapping of quantitative trait locus (QTL) and identification of candidate genes associated with pod size are essential for genetic improvement and molecular breeding of peanut varieties. In this study, a major QTL related to pod size, qAHPS07, was fine mapped to a 36.46 kb interval on chromosome A07 using F2 , recombinant inbred line (RIL) and secondary F2 populations. qAHPS07 explained 38.6%, 23.35%, 37.48%, 25.94% of the phenotypic variation for single pod weight (SPW), pod length (PL), pod width (PW) and pod shell thickness (PST), respectively. Whole genome resequencing and gene expression analysis revealed that a RuvB-like 2 protein coding gene AhRUVBL2 was the most likely candidate for qAHPS07. Overexpression of AhRUVBL2 in Arabidopsis led to larger seeds and plants than the wild type. AhRUVBL2-silenced peanut seedlings represented small leaves and shorter main stems. Three haplotypes were identified according to three SNPs in the promoter of AhRUVBL2 among 119 peanut accessions. Among them, SPW, PW and PST of accessions carrying Hap_ATT represent 17.6%, 11.2% and 26.3% higher than those carrying Hap_GAC，respectively. In addition, a functional marker of AhRUVBL2 was developed. Taken together, our study identified a key functional gene of peanut pod size, which provides new insights into peanut pod size regulation mechanism and offers practicable markers for the genetic improvement of pod size-related traits in peanut breeding.

High-Quantum-Efficiency Blue Phosphors with Superior Thermal Stability Derived from Eu3+-Doped Faujasite Y Zeolite.

Blue phosphors of high efficiency and superior thermal stability constitute the critical component for achieving high-quality white light-emitting diodes (WLEDs). Herein, we report a highly efficient blue-emitting phosphor with superior thermal stability by heating Eu3+-doped Faujasite Y zeolite under a reducing atmosphere. The intensity and peak value of the phosphor are highly dependent on calcination temperature, and the intensity of PLE and PL spectra reaches a maximum at 1100 °C. Under the excitation of 360 nm, the phosphor shows a high quantum efficiency (90%) and thermal stability (the emission intensity at 423 K is about 125% of that at room temperature). WLEDs fabricated using this blue phosphor, a yellow Eu2+-SOD phosphor, and a commercially available red Sr2Si5N8:Eu2+ phosphor exhibit an excellent optical performance with a correlated color temperature of 4359 K and a color rendering index of 97. This work provides a new strategy for the synthesis of phosphors with high thermal stability and luminous efficiency.

Secondary Hyperparathyroidism: Clinical Exploration of Endoscopic Total Parathyroidectomy Using the Oral Vestibular Approach with Forearm Autotransplantation.

Context: For secondary hyperparathyroidism (SHPT), physicians prefer conservative treatments, and surgical intervention has proven to be the best solution for some patients. Among the surgical interventions, total parathyroidectomy plus autotransplantation (TPTX+AT), using the forearm, is the major effective treatment. TPTX+AT, in conjunction with transoral endoscopic thyroidectomy vestibular approach (TOETVA), includes many advantages. Objective: The study intended to evaluate the clinical value of performing an endoscopic total parathyroidectomy TPTX+AT in conjunction with TOETVA in treating SHPT and to summarize and share the clinical experience. Design: The research team performed a prospective controlled study. Setting: The study took place at the Zhongshan Boai Hospital affiliated with Southern Medical University in Zhong Shan, Guangdong, China. Participants: Participants were 97 SHPT patients who were admitted to the hospital between March 2020 and March 2022. Intervention: The intervention group included 47 SHPT patients who received endoscopic TPTX+AT combined with the TOETVA, and the control group included 50 SHPT patients who received routine TPTX+AT. Outcome Measures: The research team performed comparisons between the groups regarding: (1) operating conditions, including intraoperative blood loss, operating time, and number of parathyroid glands detected intraoperatively; (2) clinical efficacy, (3) postoperative complications, (4) parathyroid hormone (PTH) and calcium (Ca) levels, (5) psychological status using the Hamilton Anxiety (HAMA) and the Hamilton Depression Scale (HAMD), and (9) life quality using the 36-Item Short Form Health Survey (SF-36). Results: The intervention group had significantly longer operation times and significantly greater intraoperative blood loss than the control group did, but the intervention group had fewer complications, lower PTH and Ca levels, and a higher efficacy (P < .05). The intervention group also had a significantly better psychological state and prognostic quality of life than the control group did (P < .05). Conclusions: Endoscopic treatment of SHPT using TPTX+AT in combination with TOETVA can significantly relieve clinical symptoms and lower serum PTH and Ca levels. The results suggest that the operation is safe and effective.

Pro-resolving and anti-inflammatory effects of resolvins and protectins in rheumatoid arthritis.

Rheumatoid arthritis (RA) is typified by persistent joint inflammation, which leads to the deterioration of bone and cartilage and a reduction in overall quality of life. The global prevalence of pain as a primary symptom in RA is influenced by the interplay between inflammation and its resolution. The identification of a family of lipid mediators known as specialized pro-resolving mediators (SPM)s has contributed to the progress of our comprehension of inflammatory conditions. SPMs have been observed to trigger the process of inflammation resolution, thereby reinstating the homeostasis of the inflammatory response. Autacoids are synthesized through the stereo-selective transformation of essential fatty acids, resulting in molecules dynamically modulated during inflammation and possessing strong immunoregulatory properties. This review delves into the available evidence that supports the involvement of certain SPM as protective lipids, biomarkers with potential, and therapeutic targets in the context of RA.

Genome-wide characterization and identification of candidate ERF genes involved in various abiotic stress responses in sesame (Sesamum indicum L.).

BACKGROUND: The adverse effects of climate change on crop production are constraining breeders to develop high-quality environmentally stable varieties. Hence, efforts are being made to identify key genes that could be targeted for enhancing crop tolerance to environmental stresses. ERF transcription factors play an important role in various abiotic stresses in plants. However, the roles of the ERF family in abiotic stresses tolerance are still largely unknown in sesame, the "queen" of oilseed crops. RESULTS: In total, 114 sesame ERF genes (SiERFs) were identified and characterized. 96.49% of the SiERFs were distributed unevenly on the 16 linkage groups of the sesame genome. The phylogenetic analysis with the Arabidopsis ERFs (AtERFs) subdivided SiERF subfamily proteins into 11 subgroups (Groups I to X; and VI-L). Genes in the same subgroup exhibited similar structure and conserved motifs. Evolutionary analysis showed that the expansion of ERF genes in sesame was mainly induced by whole-genome duplication events. Moreover, cis-acting elements analysis showed that SiERFs are mostly involved in environmental responses. Gene expression profiles analysis revealed that 59 and 26 SiERFs are highly stimulated under drought and waterlogging stress, respectively. In addition, qRT-PCR analyses indicated that most of SiERFs are also significantly up-regulated under osmotic, submerge, ABA, and ACC stresses. Among them, SiERF23 and SiERF54 were the most induced by both the abiotic stresses, suggesting their potential for targeted improvement of sesame response to multiple abiotic stresses. CONCLUSION: This study provides a comprehensive understanding of the structure, classification, evolution, and abiotic stresses response of ERF genes in sesame. Moreover, it offers valuable gene resources for functional characterization towards enhancing sesame tolerance to multiple abiotic stresses.

High-resolution temporal transcriptome sequencing unravels ERF and WRKY as the master players in the regulatory networks underlying sesame responses to waterlogging and recovery.

Major crops are generally sensitive to waterlogging, but our limited understanding of the waterlogging gene regulatory network hinders the efforts to develop waterlogging-tolerant cultivars. We generated high-resolution temporal transcriptome data from root of two contrasting sesame genotypes over a 48 h period waterlogging and drainage treatments. Three distinct chronological transcriptional phases were identified, including the early-waterlogging, late-waterlogging and drainage responses. We identified 47 genes representing the core waterlogging-responsive genes. Waterlogging/drainage-induced transcriptional changes were mainly driven by ERF and WRKY transcription factors (TF). The major difference between the two genotypes resides in the early transcriptional phase. A chronological transcriptional network model predicting putative causal regulations between TFs and downstream waterlogging-responsive genes was constructed and some interactions were validated through yeast one-hybrid assay. Overall, this study unveils the architecture and dynamic regulation of the waterlogging/drainage response in a non-model crop and helps formulate new hypotheses on stress sensing, signaling and sophisticated adaptive responses.

Genome-Wide Identification of Auxin Response Factors in Peanut (Arachis hypogaea L.) and Functional Analysis in Root Morphology.

Auxin response factors (ARFs) play important roles in plant growth and development; however, research in peanut (Arachis hypogaea L.) is still lacking. Here, 63, 30, and 30 AhARF genes were identified from an allotetraploid peanut cultivar and two diploid ancestors (A. duranensis and A. ipaensis). Phylogenetic tree and gene structure analysis showed that most AhARFs were highly similar to those in the ancestors. By scanning the whole-genome for ARF-recognized cis-elements, we obtained a potential target gene pool of AhARFs, and the further cluster analysis and comparative analysis showed that numerous members were closely related to root development. Furthermore, we comprehensively analyzed the relationship between the root morphology and the expression levels of AhARFs in 11 peanut varieties. The results showed that the expression levels of AhARF14/26/45 were positively correlated with root length, root surface area, and root tip number, suggesting an important regulatory role of these genes in root architecture and potential application values in peanut breeding.

[Preparation of salvianolic acid B, tanshinone â ¡_A, and glycyrrhetinic acid lipid emulsion and its protective effect against acute liver injury induced by acetaminophen].

Salvianolic acid B(Sal B), tanshinone Ⅱ_A(TSN Ⅱ_A), and glycyrrhetinic acid(GA) lipid emulsion(GTS-LE) was prepared by the high-speed dispersion method combined with ultrasonic emulsification.The preparation process of the emulsion was optimized by single-factor method and D-optimal method with appearance, centrifugal stability, and particle size of the emulsion as evalua-tion indexes, followed by verification.In vitro release of Sal B, TSN Ⅱ_A, and GA in GTS-LE was performed by reverse dialysis.In vivo pharmacokinetic evaluation was carried out in mice.The acute liver injury model was induced by acetaminophen.The effect of oral GTS-LE on the acute liver injury was investigated by serum liver function indexes and pathological changes in liver tissues of mice.The results showed that under the optimal preparation process, the average particle size of GTS-LE was(145.4±9.25) nm and the Zeta potential was(-33.6±1.45) mV.The drug-loading efficiencies of Sal B, TSN Ⅱ_A, and GA in GTS-LE were above 95%, and the drug release in vitro conformed to the Higuchi equation.The pharmacokinetic results showed that the C_(max) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.128, 2.7, and 2.85 times that of the GTS-S group, and AUC_(0-t) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.09, 2.23, and 1.9 times that of the GTS-S group.After intragastric administration of GTS-LE, the activities of alanine aminotransferase and aspartate aminotransferase were significantly inhibited, the content of malondialdehyde was reduced, and the structure of hepatocytes recovered to normal.In conclusion, GTS-LE can delay the release of Sal B and promote the release of TSN Ⅱ_A and GA.The encapsulation of three drug components in the emulsion can improve the oral bioavailability to varying degrees and can effectively prevent the acute liver injury caused by acetaminophen.

Genome-wide association study and its applications in the non-model crop Sesamum indicum.

BACKGROUND: Sesame is a rare example of non-model and minor crop for which numerous genetic loci and candidate genes underlying features of interest have been disclosed at relatively high resolution. These progresses have been achieved thanks to the applications of the genome-wide association study (GWAS) approach. GWAS has benefited from the availability of high-quality genomes, re-sequencing data from thousands of genotypes, extensive transcriptome sequencing, development of haplotype map and web-based functional databases in sesame. RESULTS: In this paper, we reviewed the GWAS methods, the underlying statistical models and the applications for genetic discovery of important traits in sesame. A novel online database SiGeDiD ( http://sigedid.ucad.sn/ ) has been developed to provide access to all genetic and genomic discoveries through GWAS in sesame. We also tested for the first time, applications of various new GWAS multi-locus models in sesame. CONCLUSIONS: Collectively, this work portrays steps and provides guidelines for efficient GWAS implementation in sesame, a non-model crop.

A novel motif in the 5'-UTR of an orphan gene 'Big Root Biomass' modulates root biomass in sesame.

Developing crops with improved root system is crucial in current global warming scenario. Underexploited crops are valuable reservoirs of unique genes that can be harnessed for the improvement of major crops. In this study, we performed genome-wide association studies on seven root traits in sesame (Sesamum indicum L.) and uncovered 409 significant signals, 19 quantitative trait loci containing 32 candidate genes. A peak SNP significantly associated with root number and root dry weight traits was located in the promoter of the gene named 'Big Root Biomass' (BRB), which was subsequently validated in a bi-parental population. BRB has no functional annotation and is restricted to the Lamiales order. We detected the presence of a novel motif 'AACACACAC' located in the 5'-UTR of BRB in single and duplicated copy in accessions with high and small root biomass, respectively. A strong expression level of BRB was negatively correlated with high root biomass, and this was attributed to the gene SiMYB181 which represses the activity of BRB by binding specifically to the single motif but not to the duplicated one. Curiously, the allele that enhanced BRB expression has been intensively selected by modern breeding. Overexpression of BRB in Arabidopsis modulates auxin pathway leading to reduced root biomass, improved yield parameters under normal growth conditions and increased drought stress sensitivity. Overall, BRB represents a solid gene model for improving the performance of sesame and other crops.

Optimizing Fe-Based Metal-Organic Frameworks through Ligand Conformation Regulation for Efficient Dye Adsorption and C2 H2 /CO2 Separation.

Regulating the structure of metal-organic frameworks (MOFs) by adjusting the ligands reasonably is expected to enhance the interaction of MOFs on special molecules/ions, which has significant application value for the selective adsorption of guest molecules. Herein, two tricarboxylic ligands H3 L-Cl and H3 L-NH2 were designed and synthesized based on the ligand H3 TTCA by replacing part of the benzene rings with C=C bonds and modifying the chlorine and amino groups on the 4-position of the benzene ring. Two 3D Fe-MOFs (UPC-60-Cl and UPC-60-NH2 ) with the new topology types were constructed. As the C=C bonds of the ligands have flexible torsion angles, UPC-60-Cl features three types of irregular 2D channels, while UPC-60-NH2 has a cage with two types of windows on the surface. The synergistic effect of unique channels and modification of functional groups endows UPC-60-Cl and UPC-60-NH2 with high adsorption capacity for organic dyes. Compound UPC-60-Cl shows high adsorption capacity for CV (147.2 mg g-1 ), RHB (100.3 mg g-1 ), and MO (220.9 mg g-1 ), whereas UPC-60-NH2 exhibits selective adsorption of MO (158.7 mg g-1 ). Meanwhile, based on the diverse pore structure and modification of active sites, UPC-60-Cl and UPC-60-NH2 show the selective separation of equimolar C2 H2 /CO2 . Therefore, reasonable regulation of organic ligands plays a significant role in guiding the structure diversification and performance improvement of MOFs.

Genome-Wide Analysis of nsLTP Gene Family and Identification of SiLTPs Contributing to High Oil Accumulation in Sesame (Sesamum indicum L.).

The biosynthesis and storage of lipids in oil crop seeds involve many gene families, such as nonspecific lipid-transfer proteins (nsLTPs). nsLTPs are cysteine-rich small basic proteins essential for plant development and survival. However, in sesame, information related to nsLTPs was limited. Thus, the objectives of this study were to identify the Sesamum indicum nsLTPs (SiLTPs) and reveal their potential role in oil accumulation in sesame seeds. Genome-wide analysis revealed 52 SiLTPs, nonrandomly distributed on 10 chromosomes in the sesame variety Zhongzhi 13. Following recent classification methods, the SiLTPs were divided into nine types, among which types I and XI were the dominants. We found that the SiLTPs could interact with several transcription factors, including APETALA2 (AP2), DNA binding with one finger (Dof), etc. Transcriptome analysis showed a tissue-specific expression of some SiLTP genes. By integrating the SiLTPs expression profiles and the weighted gene co-expression network analysis (WGCNA) results of two contrasting oil content sesame varieties, we identified SiLTPI.23 and SiLTPI.28 as the candidate genes for high oil content in sesame seeds. The presumed functions of the candidate gene were validated through overexpression of SiLTPI.23 in Arabidopsis thaliana. These findings expand our knowledge on nsLTPs in sesame and provide resources for functional studies and genetic improvement of oil content in sesame seeds.

Comprehensive Analysis of SRO Gene Family in Sesamum indicum (L.) Reveals Its Association with Abiotic Stress Responses.

SIMILAR TO RCD-ONEs (SROs) comprise a small plant-specific gene family which play important roles in regulating numerous growth and developmental processes and responses to environmental stresses. However, knowledge of SROs in sesame (Sesamum indicum L.) is limited. In this study, four SRO genes were identified in the sesame genome. Phylogenetic analysis showed that 64 SROs from 10 plant species were divided into two groups (Group I and II). Transcriptome data revealed different expression patterns of SiSROs over various tissues. Expression analysis showed that Group II SROs, especially SiSRO2b, exhibited a stronger response to various abiotic stresses and phytohormones than those in Group I, implying their crucial roles in response to environmental stimulus and hormone signals. In addition, the co-expression network and protein-protein interaction network indicated that SiSROs are associated with a wide range of stress responses. Moreover, transgenic yeast harboring SiSRO2b showed improved tolerance to salt, osmotic and oxidative stress, indicating SiSRO2b could confer multiple tolerances to transgenic yeast. Taken together, this study not only lays a foundation for further functional dissection of the SiSRO gene family, but also provides valuable gene candidates for genetic improvement of abiotic stress tolerance in sesame.

Integrated small RNA and Degradome sequencing provide insights into salt tolerance in sesame (Sesamum indicum L.).

BACKGROUND: MicroRNAs (miRNAs) exhibit important regulatory roles in the response to abiotic stresses by post-transcriptionally regulating the target gene expression in plants. However, their functions in sesame response to salt stress are poorly known. To dissect the complex mechanisms underlying salt stress response in sesame, miRNAs and their targets were identified from two contrasting sesame genotypes by a combined analysis of small RNAs and degradome sequencing. RESULTS: A total of 351 previously known and 91 novel miRNAs were identified from 18 sesame libraries. Comparison of miRNA expressions between salt-treated and control groups revealed that 116 miRNAs were involved in salt stress response. Using degradome sequencing, potential target genes for some miRNAs were also identified. The combined analysis of all the differentially expressed miRNAs and their targets identified miRNA-mRNA regulatory networks and 21 miRNA-mRNA interaction pairs that exhibited contrasting expressions in sesame under salt stress. CONCLUSIONS: This comprehensive integrated analysis may provide new insights into the genetic regulation mechanism of miRNAs underlying the adaptation of sesame to salt stress.

Optimizing Multivariate Metal-Organic Frameworks for Efficient C2H2/CO2 Separation.

Adsorptive separation of acetylene (C2H2) from carbon dioxide (CO2) promises a practical way to produce high-purity C2H2 required for industrial applications. However, challenges exist in the pore environment engineering of porous materials to recognize two molecules due to their similar molecular sizes and physical properties. Herein, we report a strategy to optimize pore environments of multivariate metal-organic frameworks (MOFs) for efficient C2H2/CO2 separation by tuning metal components, functionalized linkers, and terminal ligands. The optimized material UPC-200(Al)-F-BIM, constructed from Al3+ clusters, fluorine-functionalized organic linkers, and benzimidazole terminal ligands, demonstrated the highest separation efficiency (C2H2/CO2 uptake ratio of 2.6) and highest C2H2 productivity among UPC-200 systems. Experimental and computational studies revealed the contribution of small pore size and polar functional groups on the C2H2/CO2 selectivity and indicated the practical C2H2/CO2 separation of UPC-200(Al)-F-BIM.

Fabrication of (4, 10) and (4, 12)-Connected Multifunctional Zirconium Metal-Organic Frameworks for the Targeted Adsorption of a Guest Molecule.

Following the principle of a topology guide, a zirconium MOF (PCN-207) based on the H4TPTA ligand (tetramethyl(4,4',4″,4‴-(pyrazine-2,3,5,6-tetrayl))tetrabenzoic acid) with C2 symmetry and an 8-connected Zr6(µ3-OH)8(OH)8]8+ cluster with D4h symmetry has been synthesized. PCN-206 can also be obtained by modulating the benzoic acid usage to change the flexibility of the H4TPTA ligand. The unique positions of 8-connected Zr6 clusters in the flu and scu networks and the flexibility of the tetratopic primary linker enable the precise insertion of fumarate (FA), 1,4-benzenedicarboxylic acid (H2BDC), and even 2,6-naphthalenedicarboxylic acid (H2NDC) in a one-pot reaction. Auxiliary linkers are used to generate new MOF structures or topologies or to split the pore spaces, which may significantly change the porosity and chemical and physical properties of scaffold MOFs. The results provide a successful strategy for the rational design of multicomponent Zr-MOFs. Because of differences in composition and configuration between structures, PCN-207 shows the highest separation capability of light hydrocarbons; moreover, PCN-206 exhibits the highest adsorption capacity of 2,4-D and DCF among MOFs at present.

Genome-wide characterization and expression analysis of the HD-Zip gene family in response to drought and salinity stresses in sesame.

BACKGROUND: The homeodomain-leucine zipper (HD-Zip) gene family is one of the plant-specific transcription factor families, involved in plant development, growth, and in the response to diverse stresses. However, comprehensive analysis of the HD-Zip genes, especially those involved in response to drought and salinity stresses is lacking in sesame (Sesamum indicum L.), an important oil crop in tropical and subtropical areas. RESULTS: In this study, 45 HD-Zip genes were identified in sesame, and denominated as SiHDZ01-SiHDZ45. Members of SiHDZ family were classified into four groups (HD-Zip I-IV) based on the phylogenetic relationship of Arabidopsis HD-Zip proteins, which was further supported by the analysis of their conserved motifs and gene structures. Expression analyses of SiHDZ genes based on transcriptome data showed that the expression patterns of these genes were varied in different tissues. Additionally, we showed that at least 75% of the SiHDZ genes were differentially expressed in responses to drought and salinity treatments, and highlighted the important role of HD-Zip I and II genes in stress responses in sesame. CONCLUSIONS: This study provides important information for functional characterization of stress-responsive HD-Zip genes and may contribute to the better understanding of the molecular basis of stress tolerance in sesame.

Topology Exploration in Highly Connected Rare-Earth Metal-Organic Frameworks via Continuous Hindrance Control.

The structural diversity of highly connected metal-organic frameworks (MOFs) has long been limited due to the scarcity of highly connected metal clusters and the corresponding available topology. Herein, we deliberately chose a series of tritopic linkers with multiple substituents to construct a series of highly connected rare-earth (RE) MOFs. The steric hindrance of these substituents can be systematically tuned to generate various linker rotamers with tunable configurations and symmetries. For example, the methyl-functionalized linker (L-CH3) with C2 v symmetry exhibits larger steric hindrance, forcing two peripheral phenyl rings perpendicular to the central one. The combination of C2 v linkers and 9-connected RE6 clusters leads to the formation of a new fascinating (3,9)-c sep topology. Unlike Zr-MOFs exhibiting Zr6 clusters in various linker configurations and corresponding different structures, the adaptable RE6 clusters can undergo metal insertion and rearrange into new RE9 clusters when connected to an unfunctionalized linker (L-H) with C1 symmetry, giving rise to a new (3,3,18)-c ytw topology. More interestingly, by judiciously combining the linkers with both small and bulky substituents through mixed-linker strategies, an RE9-based MOF with an engaging (3,3,12)-c flg topology could be obtained as a result of continuous steric hindrance control. In this case, the two mixed linkers adopt configurations with moderate steric hindrances. Molecular simulation demonstrates that the combination of substituents with various steric hindrances dictates the resulting MOF structures. This work provides insights into the discovery of unprecedented topologies through systematic and continuous steric tuning, which can further serve as a blueprint for the design and construction of highly complicated porous structures for sophisticated applications.

Transcriptome and metabolome analyses of two contrasting sesame genotypes reveal the crucial biological pathways involved in rapid adaptive response to salt stress.

BACKGROUND: Soil salinity is one of the major serious factors that affect agricultural productivity of almost all crops worldwide, including the important oilseed crop sesame. In order to improve salinity resistance in sesame, it is crucial to understand the molecular mechanisms underlying the adaptive response to salinity stress. RESULTS: In the present study, two contrasting sesame genotypes differing in salt tolerance were used to decipher the adaptive responses to salt stress based on morphological, transcriptome and metabolome characterizations. Morphological results indicated that under salt stress, the salt-tolerant (ST) genotype has enhanced capacity to withstand salinity stress, higher seed germination rate and plant survival rate, as well as better growth rate than the salt-sensitive genotype. Transcriptome analysis revealed strongly induced salt-responsive genes in sesame mainly related to amino acid metabolism, carbohydrate metabolism, biosynthesis of secondary metabolites, plant hormone signal transduction, and oxidation-reduction process. Especially, several pathways were preferably enriched with differentially expressed genes in ST genotype, including alanine, aspartate and glutamate metabolism, carotenoid biosynthesis, galactose metabolism, glycolysis/gluconeogenesis, glyoxylate and dicarboxylate metabolism, porphyrin and chlorophyll metabolism. Metabolome profiling under salt stress showed a higher accumulation degree of metabolites involved in stress tolerance in ST, and further highlighted that the amino acid metabolism, and sucrose and raffinose family oligosaccharides metabolism were enhanced in ST. CONCLUSIONS: These findings suggest that the candidate genes and metabolites involved in crucial biological pathways may regulate salt tolerance of sesame, and increase our understanding of the molecular mechanisms underlying the adaptation of sesame to salt stress.