NF1-cAMP signaling dissociates cell type-specific contributions of striatal medium spiny neurons to reward valuation and motor control.

The striatum plays a fundamental role in motor learning and reward-related behaviors that are synergistically shaped by populations of D1 dopamine receptor (D1R)- and D2 dopamine receptor (D2R)-expressing medium spiny neurons (MSNs). How various neurotransmitter inputs converging on common intracellular pathways are parsed out to regulate distinct behavioral outcomes in a neuron-specific manner is poorly understood. Here, we reveal that distinct contributions of D1R-MSNs and D2R-MSNs towards reward and motor behaviors are delineated by the multifaceted signaling protein neurofibromin 1 (NF1). Using genetic mouse models, we show that NF1 in D1R-MSN modulates opioid reward, whereas loss of NF1 in D2R-MSNs delays motor learning by impeding the formation and consolidation of repetitive motor sequences. We found that motor learning deficits upon NF1 loss were associated with the disruption in dopamine signaling to cAMP in D2R-MSN. Restoration of cAMP levels pharmacologically or chemogenetically rescued the motor learning deficits seen upon NF1 loss in D2R-MSN. Our findings illustrate that multiplex signaling capabilities of MSNs are deployed at the level of intracellular pathways to achieve cell-specific control over behavioral outcomes.

Separation and recovery of heavy metals zinc and lead from phosphorus flue dust by vacuum metallurgy.

Yellow phosphorous flue dust (YPFD) is a solid waste produced by the yellow phosphorus industry that contains heavy metals such as zinc (Zn) and lead (Pb), causing environmental damage. In this work, a vacuum metallurgy method is proposed to separate and recover Zn and Pb from solid waste YPFD. Under optimized conditions of 1173 K, 30 wt% reductant dosage, 60 min, and 5-10 Pa, the pre-separation of Zn and Pb was realized and the recovery rates of Zn and Pb reached 92.47% and 99.78%, respectively. In addition, gallium (Ga) remained in the residue with little loss, and then recovered by raising the reaction temperature to 1323 K. The recovery rates of Ga reached 87.57%. The principle of metal volatilization under vacuum at different temperatures was also clarified. The thermodynamic calculations of the carbothermal reduction reaction of metal oxides under vacuum were carried out. The analysis of the product obtained at 1173 K showed that Zn and Pb mainly existed in the form of elemental or simple compounds. At 1323 K, Ga in the residue was highly enriched in the condensation zone, which is conducive for the subsequent purification. The whole process is short, there is no waste water, low levels of pollution of emitted, and the technology provides a clean and sustainable way to reuse YPFD.

Comparative population genomics reveals genetic divergence and selection in lotus, Nelumbo nucifera.

BACKGROUND: Lotus (Nelumbo nucifera) is an aquatic plant with important agronomic, horticulture, art and religion values. It was the basal eudicot species occupying a critical phylogenetic position in flowering plants. After the domestication for thousands of years, lotus has differentiated into three cultivated types -flower lotus, seed lotus and rhizome lotus. Although the phenotypic and genetic differentiations based on molecular markers have been reported, the variation on whole-genome level among the different lotus types is still ambiguous. RESULTS: In order to reveal the evolution and domestication characteristics of lotus, a total of 69 lotus accessions were selected, including 45 cultivated accessions, 22 wild sacred lotus accessions, and 2 wild American lotus accessions. With Illumina technology, the genomes of these lotus accessions were resequenced to > 13× raw data coverage. On the basis of these genomic data, 25 million single-nucleotide polymorphisms (SNPs) were identified in lotus. Population analysis showed that the rhizome and seed lotus were monophyletic and genetically homogeneous, whereas the flower lotus was biphyletic and genetically heterogeneous. Using population SNP data, we identified 1214 selected regions in seed lotus, 95 in rhizome lotus, and 37 in flower lotus. Some of the genes in these regions contributed to the essential domestication traits of lotus. The selected genes of seed lotus mainly affected lotus seed weight, size and nutritional quality. While the selected genes were responsible for insect resistance, antibacterial immunity and freezing and heat stress resistance in flower lotus, and improved the size of rhizome in rhizome lotus, respectively. CONCLUSIONS: The genome differentiation and a set of domestication genes were identified from three types of cultivated lotus- flower lotus, seed lotus and rhizome lotus, respectively. Among cultivated lotus, flower lotus showed the greatest variation. The domestication genes may show agronomic importance via enhancing insect resistance, improving seed weight and size, or regulating lotus rhizome size. The domestication history of lotus enhances our knowledge of perennial aquatic crop evolution, and the obtained dataset provides a basis for future genomics-enabled breeding.

Orphan Receptor GPR158 Is an Allosteric Modulator of RGS7 Catalytic Activity with an Essential Role in Dictating Its Expression and Localization in the Brain.

Regulators of G protein signaling control the duration and extent of signaling via G protein-coupled receptor (GPCR) pathways by accelerating the GTP hydrolysis on G protein α subunits thereby promoting termination of GPCR signaling. A member of this family, RGS7, plays a critical role in the nervous system where it regulates multiple neurotransmitter GPCRs that mediate vision, memory, and the action of addictive drugs. Previous studies have established that in vivo RGS7 forms mutually exclusive complexes with the membrane protein RGS7-binding protein or the orphan receptor GPR158. In this study, we examine the impact of GPR158 on RGS7 in the brain. We report that knock-out of GPR158 in mice results in marked post-transcriptional destabilization of RGS7 and substantial loss of its association with membranes in several brain regions. We further identified the RGS7-binding site in the C terminus of GPR158 and found that it shares significant homology with the RGS7-binding protein. The proximal portion of the GPR158 C terminus additionally contained a conserved sequence that was capable of enhancing RGS7 GTPase-activating protein activity in solution by an allosteric mechanism acting in conjunction with the regulators of the G protein signaling-binding domain. The distal portion of the GPR158 C terminus contained several phosphodiesterase E γ-like motifs and selectively recruited G proteins in their activated state. The results of this study establish GPR158 as an essential regulator of RGS7 in the native nervous system with a critical role in controlling its expression, membrane localization, and catalytic activity.

Macromolecular composition dictates receptor and G protein selectivity of regulator of G protein signaling (RGS) 7 and 9-2 protein complexes in living cells.

Regulator of G protein signaling (RGS) proteins play essential roles in the regulation of signaling via G protein-coupled receptors (GPCRs). With hundreds of GPCRs and dozens of G proteins, it is important to understand how RGS regulates selective GPCR-G protein signaling. In neurons of the striatum, two RGS proteins, RGS7 and RGS9-2, regulate signaling by µ-opioid receptor (MOR) and dopamine D2 receptor (D2R) and are implicated in drug addiction, movement disorders, and nociception. Both proteins form trimeric complexes with the atypical G protein ß subunit Gß5 and a membrane anchor, R7BP. In this study, we examined GTPase-accelerating protein (GAP) activity as well as Gα and GPCR selectivity of RGS7 and RGS9-2 complexes in live cells using a bioluminescence resonance energy transfer-based assay that monitors dissociation of G protein subunits. We showed that RGS9-2/Gß5 regulated both Gi and Go with a bias toward Go, but RGS7/Gß5 could serve as a GAP only for Go. Interestingly, R7BP enhanced GAP activity of RGS7 and RGS9-2 toward Go and Gi and enabled RGS7 to regulate Gi signaling. Neither RGS7 nor RGS9-2 had any activity toward Gz, Gs, or Gq in the absence or presence of R7BP. We also observed no effect of GPCRs (MOR and D2R) on the G protein bias of R7 RGS proteins. However, the GAP activity of RGS9-2 showed a strong receptor preference for D2R over MOR. Finally, RGS7 displayed an four times greater GAP activity relative to RGS9-2. These findings illustrate the principles involved in establishing G protein and GPCR selectivity of striatal RGS proteins.

Effect of Two-Step Sintering on the Mechanical and Electrical Properties of 5YSZ and 8YSZ Ceramics.

Yttria-stabilized zirconia (YSZ) has been widely used in structural and functional ceramics because of its excellent physicochemical properties. In this paper, the density, average gain size, phase structure, and mechanical and electrical properties of conventionally sintered (CS) and two-step sintered (TSS) 5YSZ and 8YSZ are investigated in detail. As the grain size of YSZ ceramics became smaller, dense YSZ materials with a submicron grain size and low sintering temperature were optimized in terms of their mechanical and electrical properties. 5YSZ and 8YSZ in the TSS process significantly improved the plasticity, toughness, and electrical conductivity of the samples and significantly suppressed the rapid grain growth. The experimental results showed that the hardness of the samples was mainly affected by the volume density, that the maximum fracture toughness of 5YSZ increased from 3.514 MPa·m1/2 to 4.034 MPa·m1/2 in the TSS process, an increase of 14.8%, and that the maximum fracture toughness of 8YSZ increased from 1.491 MPa·m1/2 to 2.126 MPa·m1/2, an increase of 42.58%. The maximum total conductivity of the 5YSZ and 8YSZ samples under 680 °C increased from 3.52 × 10-3 S/cm and 6.09 × 10-3 S/cm to 4.52 × 10-3 S/cm and 7.87 × 10-3 S/cm, an increase of 28.41% and 29.22%, respectively.

TESOGENASE, An Engineered Nuclease Editor for Enhanced Targeted Genome Integration.

Non-viral DNA donor template has been widely used for targeted genomic integration by homologous recombination (HR). This process has become more efficient with RNA guided endonuclease editor system such as CRISPR/Cas9. Circular single stranded DNA (cssDNA) has been harnessed previously as a g enome engineering c atalyst (GATALYST) for efficient and safe targeted gene knock-in. However, the engineering efficiency is bottlenecked by the nucleoplasm trafficking and genomic tethering of cssDNA donor, especially for extra-large transgene integration. Here we developed enGager, en hanced G ATALYST a ssociated g enome e ditor system by fusion of nucleus localization signal (NLS) peptide tagged Cas9 with various single stranded DNA binding protein modules through a GFP reporter Knock-in screening. The enGager system assembles an integrative genome integration machinery by forming tripartite complex for engineered nuclease editors, sgRNA and ssDNA donors, thereby facilitate the nucleus trafficking of DNA donors and increase their active local concentration at the targeted genomic site. When applied for genome integration with cssDNA donor templates to diverse genomic loci in various cell types, these enGagers outperform unfused editors. The enhancement of integration efficiency ranges from 1.5- to more than 6-fold, with the effect being more prominent for > 4Kb transgene knock-in in primary cells. We further demonstrated that enGager mediated enhancement for genome integration is ssDNA, but less dsDNA dependent. Using one of the mini-enGagers, we demonstrated large chimeric antigen receptor (CAR) transgene integration in primary T cells with exceptional efficiency and anti-tumor function. These tripartite e ditors with s sDNA o ptimized g enome en gineering system (TESOGENASE TM ) add a set of novel endonuclease editors into the gene-editing toolbox for potential cell and gene therapeutic development based on ssDNA mediated non-viral genome engineering. Highlight: A reporter Knock-in screening establishes enGager system to identify TESOGENASE editor to improving ssDNA mediated genome integrationMini-TESOGENASEs developed by fusing Cas9 nuclease with novel ssDNA binding motifsmRNA mini-TESOGENASEs enhance targeted genome integration via various non-viral delivery approachesEfficient functional CAR-T cell engineering by mini-TESOGENASE.

Engineering Tripartite Gene Editing Machinery for Highly Efficient Non-Viral Targeted Genome Integration.

Non-viral DNA donor template has been widely used for targeted genomic integration by homologous recombination (HR). This process has become more efficient with RNA guided endonuclease editor system such as CRISPR/Cas9. Circular single stranded DNA (cssDNA) has been harnessed previously as a genome engineering catalyst (GATALYST) for efficient and safe targeted gene knock-in. Here we developed enGager, a system with enhanced GATALYST associated genome editor, comprising a set of novel genome editors in which the integration efficiency of a circular single-stranded (css) donor DNA is elevated by directly tethering of the cssDNA to a nuclear-localized Cas9 fused with ssDNA binding peptides. Improvements in site-directed genomic integration and expression of a knocked-in DNA encoding GFP were observed at multiple genomic loci in multiple cell lines. The enhancement of integration efficiency, compared to unfused Cas9 editors, ranges from 1.5- to more than 6-fold, with the enhancement most pronounced for transgenes of > 4Kb in length in primary cells. enGager-enhanced genome integration prefers ssDNA donors which, unlike traditional dsDNA donors, are not concatemerized or rearranged prior to and during integration Using an enGager fused to an optimized cssDNA binding peptide, exceptionally efficient, targeted integration of the chimeric antigen receptor (CAR) transgene was achieved in 33% of primary human T cells. Enhanced anti-tumor function of these CAR-T primary cells demonstrated the functional competence of the transgenes. The 'tripartite editors with ssDNA optimized genome engineering' (TESOGENASE™) systems help address the efficacy needs for therapeutic gene modification while avoiding the safety and payload size limitations of viral vectors currently used for CAR-T engineering.

The Concise Guide to PHARMACOLOGY 2023/24: Introduction and Other Protein Targets.

The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and about 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.16176. In addition to this overview, in which are identified 'Other protein targets' which fall outside of the subsequent categorisation, there are six areas of focus: G protein-coupled receptors, ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2023, and supersedes data presented in the 2021/22, 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.

A clean process for phosphorus recovery and gallium enrichment from phosphorus flue dust by sodium carbonate roasting.

Phosphorus flue dust (PFD) is a solid waste product from phosphorus (P) production that contains P and is enriched with gallium (Ga). The recovery of these valuable components not only protects the environment, but also reduces resource waste. This study aimed to develop a green and efficient method to recover P and enriched Ga from PFD. The effects of different parameters on the P leaching rate and Ga loss rate during Na2CO3 roasting and water leaching were investigated and optimized. The reaction mechanisms during the experiment were characterized, revealing that the P-containing compounds in PFD mainly transformed into water-soluble Na3PO4. Furthermore, the leaching rate of P reached 85.38%, while Ga was mainly concentrated in the residue and its loss rate was only about 1%. Ga content in the residue reached about 0.1%. An attempt was made to recover Na+ and PO43- from the aqueous solution by evaporative crystallization and XRD analysis showed that the main phase of the crystallization product was Na2HPO4. The proposed process is technically simple, only Na2CO3 is added and no hazardous substances are generated, and represents a new method for recovering P and enriching Ga from PFD.

Genomic variation reveals demographic history and biological adaptation of the ancient relictual, lotus (Nelumbo Adans).

Lotus (Nelumbo Adans.), a relict plant, is the testimony of long-term sustained ecological success, but the underlying genetic changes related to its survival strategy remains unclear. Here, we assembled the high-quality lotus genome, investigated genome variation of lotus mutation accumulation (MA) lines and reconstructed the demographic history of wild Asian lotus, respectively. We identified and validated 43 base substitutions fixed in MA lines, implying a spontaneous mutation rate of 1.4 × 10-9 base/generation in lotus shoot stem cells. The past history of lotus revealed that the ancestors of lotus in eastern and southern Asia could be traced back ~20 million years ago (Mya) and experienced twice significant bottlenecks and population splits. We further identified the selected genes among three lotus groups in different habitats, suggesting that 453 genes between tropical and temperate group and 410 genes between two subgroups from Northeastern China and the Yangtze River - Yellow River Basin might play important roles in natural selection in lotus's adaptation and resilience. Our findings not only improve an understanding of the lotus evolutionary history and the genetic basis of its survival advantages, but also provide valuable data for addressing various questions in evolution and protection for the relict plants.

A conserved protein interaction interface on the type 5 G protein beta subunit controls proteolytic stability and activity of R7 family regulator of G protein signaling proteins.

Regulators of G protein signaling (RGS) proteins of the R7 subfamily limit signaling by neurotransmitters in the brain and by light in the retina. They form obligate complexes with the Gß5 protein that are subject to proteolysis to control their abundance and alter signaling. The mechanisms that regulate this proteolysis, however, remain unclear. We used genetic screens to find mutations in Gß5 that selectively destabilize one of the R7 RGS proteins in Caenorhabditis elegans. These mutations cluster at the binding interface between Gß5 and the N terminus of R7 RGS proteins. Equivalent mutations within mammalian Gß5 allowed the interface to still bind the N-terminal DEP domain of R7 RGS proteins, and mutant Gß5-R7 RGS complexes initially formed in cells but were then rapidly degraded by proteolysis. Molecular dynamics simulations suggest the mutations weaken the Gß5-DEP interface, thus promoting dynamic opening of the complex to expose determinants of proteolysis known to exist on the DEP domain. We propose that conformational rearrangements at the Gß5-DEP interface are key to controlling the stability of R7 RGS protein complexes.

Inhibition of PDE2 and PDE4 synergistically improves memory consolidation processes.

Phosphodiesterases (PDE) are the only enzymes that degrade cAMP and cGMP which are second messengers crucial to memory consolidation. Different PDE inhibitors have been developed and tested for their memory-enhancing potential, but the occurrence of side effects has hampered clinical progression. As separate inhibition of the PDE2 and PDE4 enzyme family has been shown to enhance memory, we investigated whether concurrent treatment with a PDE2 and PDE4 inhibitor can have synergistic effects on memory consolidation processes. We found that combined administration of PF-999 (PDE2 inhibitor) and roflumilast (PDE4 inhibitor) increases the phosphorylation of the AMPA receptor subunit GluR1 and induces CRE-mediated gene expression. Moreover, when combined sub-effective and effective doses of PF-999 and roflumilast were administered after learning, time-dependent forgetting was abolished in an object location memory task. Pharmacokinetic assessment indicated that combined treatment does not alter exposure of the individual compounds. Taken together, these findings suggest that combined PDE2 and PDE4 inhibition has synergistic effects on memory consolidation processes at sub-effective doses, which could therefore provide a therapeutic strategy with an improved safety profile.

Retina-specific GTPase accelerator RGS11/G beta 5S/R9AP is a constitutive heterotrimer selectively targeted to mGluR6 in ON-bipolar neurons.

Members of the R7 family of the regulators of G-protein signaling (R7 RGS) proteins form multi-subunit complexes that play crucial roles in processing the light responses of retinal neurons. The disruption of these complexes has been shown to lead to the loss of temporal resolution in retinal photoreceptors and deficient synaptic transmission to downstream neurons. Despite the well established role of one member of this family, RGS9-1, in controlling vertebrate phototransduction, the roles and organizational principles of other members in the retina are poorly understood. Here we investigate the composition, localization, and function of complexes containing RGS11, the closest homolog of RGS9-1. We find that RGS11 forms a novel obligatory trimeric complex with the short splice isoform of the type 5 G-protein beta subunit (G beta 5) and the RGS9 anchor protein (R9AP). The complex is expressed exclusively in the dendritic tips of ON-bipolar cells in which its localization is accomplished through a direct association with mGluR6, the glutamate receptor essential for the ON-bipolar light response. Although association with both R9AP and mGluR6 contributed to the proteolytic stabilization of the complex, postsynaptic targeting of RGS11 was not determined by its membrane anchor R9AP. Electrophysiological recordings of the light response in mouse rod ON-bipolar cells reveal that the genetic elimination of RGS11 has little effect on the deactivation of G alpha(o) in dark-adapted cells or during adaptation to background light. These results suggest that the deactivation of mGluR6 cascade during the light response may require the contribution of multiple GTPase activating proteins.

A new method of recycling gallium from yellow phosphorus flue dust by vacuum thermal reduction process.

Gallium is widely used in the field of semiconductors, and is mainly recovered as a by-product from other production processes utilizing metals such as aluminum and zinc. As a waste generated during the production of yellow phosphorus, yellow phosphorus flue dust is a potential resource for recovery of gallium. In this study, vacuum carbothermic reduction technology was applied to extract gallium from yellow phosphorus flue dust. Under the optimal conditions of 1323 K, 40 min holding time, 50 wt% carbon content, and 1-10 Pa, the recovery rate of gallium was 92.5 %. The condensate was analyzed and the enrichment area of gallium in the condensation zone was determined. No hazardous gases and materials were generated during the process. Compared with other methods of recovering gallium from yellow phosphorus flue dust by hydrometallurgical process, this study has the advantages of short process, easy collection of products, low energy consumption. Overall, this work demonstrates a new and environmentally friendly method for the recovery of gallium from yellow phosphorus flue dust, and also provides a reference value for the comprehensive utilization of this material.

Development and identification of three functional markers associated with starch content in lotus (Nelumbo nucifera).

It have been significantly demonstrated that Hexokinase (HXK), Granule-bound starch synthase (GBSS) and ADP-glucose pyrophosphorylase (AGPase) are three critical enzymes in the starch biosynthetic pathway and are related to starch (amylose, amylopectin and total starch) content in lotus. It is important to develop functional markers in marker-assisted selection of lotus breeding. So far there have been few reports about lotus functional markers. In this study, based on insertion-deletions (INDELs) and single-nucleotide polymorphisms (SNPs), we developed three functional markers, FMHXK-E1, FMGBSS-I8 and FMAGPL-I1. FMHXK-E1 was developed based on polymorphisms of two haplotypes of NnHXK. 26 lotus cultivars that the 320-bp fragment presented in NnHXK had a lower content of amylose and a higher content of amylopectin. FMGBSS-I8 was developed based on polymorphisms of two haplotypes of NnGBSS. The group containing 32 lotus cultivars with the 210-bp fragment had less amylose content and more amylopectin content. FMAGPL-I1 was developed based on polymorphisms of two haplotypes of NnAGPL (ADP-glucose pyrophosphorylase large subunit gene). The group containing 40 lotus cultivars with the 362-bp fragment had less amylopectin, total starch content and more amylose content. According to the study, FMHXK-E1, FMGBSS-I8 and FMAGPL-I1 are closely related to lotus starch content. It could be provided research basis for molecular assisted selection of lotus starch content improve breeding efficiency.

Adenosine A(1) receptor-mediated transactivation of the EGF receptor produces a neuroprotective effect on cortical neurons in vitro.

AIM: To understand the mechanism of the transactivation of the epidermal growth factor receptor (EGFR) mediated by the adenosine A(1) receptor (A(1)R). METHODS: Primary cultured rat cortical neurons subjected to oxygen-glucose deprivation (OGD) and HEK293/A(1)R cells were treated with the A(1)R-specific agonist N(6)-cyclopentyladenosine (CPA). Phospho-EGFR, Akt, and ERK1/2 were observed by Western blot. An interaction between EGFR and A(1)R was detected using immunoprecipitation and immunocytochemistry. RESULTS: The A(1)R agonist CPA causes protein kinase B (Akt) activation and protects primary cortical neurons from oxygen-glucose deprivation (OGD) insult. A(1)R and EGFR co-localize in the membranes of neurons and form an immunocomplex. A(1)R stimulation induces significant EGFR phosphorylation via a PI3K and Src kinase signaling pathway; this stimulation provides a neuroprotective effect in cortical neurons. CPA leads to sustained phosphorylation of extracellularly regulated kinases 1 and 2 (ERK1/2) in cortical neurons, but only to transient phosphorylation in HEK 293/A(1)R cells. The response to the A(1)R agonist is mediated primarily through EGFR transactivation that is dependent on pertussis toxin (PTX)-sensitive G(i) protein and metalloproteases in HEK 293/A(1)R. CONCLUSION: A(1)R-mediated EGFR transactivation confers a neuroprotective effect in primary cortical neurons. PI3 kinase and Src kinase play pivotal roles in this response.Acta Pharmacologica Sinica (2009) 30: 889-898; doi: 10.1038/aps.2009.80.

Genetic diversity, functional properties and expression analysis of NnSBE genes involved in starch synthesis of lotus (Nelumbo nucifera Gaertn.).

BACKGROUND: Starch branching enzyme (SBE) is one of the key enzymes in starch biosynthetic metabolism, determining amylopectin structure. METHODS: Full length coding sequences (CDS) of SBE genes were cloned using reverse transcription PCR (RT-PCR) technology, and neighbor-joining (NJ) tree was used for phylogenetic analysis. Single nucleotide polymorphisms (SNPs) were determined to assess the genetic polymorphisms and variation indexes between individuals and clusters. Quantitative real time PCR (qRT-PCR) was performed to analyze the spatial and temporal expression of NnSBE genes. The effect of NnSBE genes on amylopectin's fine structures was explored using affinity and the enzyme activity analysis of two isoforms in amylopectin and amylose. RESULTS: In this study, two SBE family genes, NnSBEI and NnSBEIII, were identified in lotus (Nelumbo nucifera Gaertn.). Phylogenetic analysis sorted NnSBEI into SBE family B and NnSBEIII into SBE family A. UPGMA phylogenetic tree divided 45 individuals of lotus into three classes. The homozygous haplotype (A G G A G) of NnSBEIII was observed in seed lotus. During the seed embryo development stage, NnSBEIII reached the peak in the middle of the development stage, while NnSBEI increased in the mid-late developmental stage. The different affinity activity of the two isozymes binding amylopectin and amylose assay indicated NnSBEI has higher activity and wider affinity. DISCUSSION: Genetic diversity showed that NnSBE genes received artificial selection during the process of cultivation and domestication in lotus seeds. Furthermore, the expression pattern and affinity activity analysis indicated that NnSBE genes were related to the chain length of amylopectin.

Kinetic mechanism of aluminum removal from diamond wire saw powder in HCl solution.

Impurity removal is essential for the recovery and regeneration of silicon resources from diamond wire saw powder by metallurgical purification technologies. In this paper, the aluminum was removed from the diamond wire saw powder via a direct HCl leaching method. In order to analyze the removal efficiency of various experimental conditions, certain parameters such as HCl concentration, leaching temperature, reaction time and liquid-solid ratio were also investigated. Particularly, the removal efficiency of Al reached 95.6% under the optimal leaching condition, such as the HCl concentration of 4 mol·L-1, the leaching temperature of 60 °C, the reaction time of 3 h, and the liquid-solid ratio of 10. The shrinking core model and homogeneous model were then respectively utilized to describe the leaching kinetics of the Al removal leaching process. The results indicated that the homogeneous model was more suitable than the shrinking core model. Moreover, the kinetics parameters regarding the reaction orders m=3, n=2.81, the activation energy Ea=97.30kJmol-1, the frequency factor A=1.11×1014 min-1. Furthermore, the leaching mechanism of Al removal was revealed based on kinetic analysis and materials characterization. This work is of great practical value in terms of regenerating silicon resources from the diamond wire saw powder waste materials with efficient and low cost methods.

Genetic Diversity and DNA Fingerprints of Three Important Aquatic Vegetables by EST-SSR Markers.

Twenty-two sacred lotus (Nelumbo nucifera), 46 taros (Colocasia esculenta) and 10 arrowheads (Sagittaria trifolia) were used as materials and combined with EST-SSR (expressed sequence tag-simple sequence repeats) primers developed by our laboratory. Core primers were screened from a large number of primers that were able to distinguish all materials with a high frequency of polymorphisms. Six pairs, twenty pairs and three pairs of core primers were screened from sacred lotus, taro, and arrowhead, respectively. The SSR fingerprints of these three important aquatic vegetables, producing 17-, 87- and 14-bit binary molecular identity cards, respectively, were separately determined by using the core primers. Since there were few core primers of sacred lotus and arrowhead, 3 and 9 primer pairs with higher polymorphic information content (PIC), respectively, were selected as candidate primers. These core and candidate primers were used to identify the purities of No.36 space lotus, Shandong 8502 taro and Wuhan arrowhead, which were 93.3% (84/90), 98.9% (89/90) and 100.0% (90/90), respectively. The fingerprints, displayed as binary molecular identification cards of three important aquatic vegetables, were obtained, and their purity was successfully determined with EST-SSR labeling technology. Phylogenetic trees were also constructed to analyze the genetic diversity of 22 sacred lotus, 46 taros and 10 arrowheads. This study classifies and identifies germplasm resources and is an important reference to test the authenticity and variety purity of other aquatic vegetables in the future.