The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike

Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.

可视化分析在病原体核酸现场快速检测中的研究进展

核酸检测因灵敏度高、特异性强而被广泛应用于病原体筛查与检测。随着检测需求的增加和扩增技术的发展,核酸检测方法逐渐向简单、快速、低成本方向发展。作为核酸检测“金标准”的实时荧光定量PCR法依赖昂贵的荧光读取设备和专业的操作人员,并不适用于病原体的现场快速检测。可视化检测方法无需依赖激发光源或复杂的设备,将可视化检测方法与快速、高效的扩增技术结合,能够以更直观、便携的方式呈现检测结果,具有即时检测(point-of-care testing,POCT)的潜力。本文对与扩增技术、CRISPR/Cas技术结合的可视化分析在病原体核酸快速检测中的应用及优缺点展开综述,以期为基于病原体核酸的POCT策略提供参考。

Enhanced electrocatalytic activity of carbon cloth by synergetic effect of plasma and acid treatment

Commercial carbon cloth(CC)is an ideal electrocatalysis material to produce oxygen evolution reaction(OER)due to its high conductive and 3D flexible structure,but the lacked active sites limit its application.For improving its OER performance,the present study proposed an effective method combining plasma and acid treatment to introduce oxygen-containing functional groups and produce more active sites on its surface.Compared to the pristine CC,the plasma and acid treated carbon cloth(PN-CC)delivers a reduced overpotential by 34.6%to achieve current density of 10 mA cm^(−2).The Tafel slope declines from 97.5 mV dec^(–1)(pristine CC)to 55.9 mV dec–1(PN-CC),showing an increased OER kinetic.Additionally,PN-CC electrocatalyst shows outstanding stability after 5000 cycles or 25000 s.The combination of plasma and acid treatment shows a significant potential in surface modification for electrocatalysts.

Comprehensive characterization of CRC with germline mutations reveals a distinct somatic mutational landscape and elevated cancer risk in the Chinese population

Objective:Hereditary colorectal cancer(CRC)accounts for approximately 5%–10%of all CRC cases.The full profile of CRC-related germline mutations and the corresponding somatic mutational profile have not been fully determined in the Chinese population.Methods:We performed the first population study investigating the germline mutation status in more than 1,000(n=1,923)Chinese patients with CRC and examined their relationship with the somatic mutational landscape.Germline alterations were examined with a 58-gene next-generation sequencing panel,and somatic alterations were examined with a 605-gene panel.Results:A total of 92 pathogenic(P)mutations were identified in 85 patients,and 81 likely pathogenic(LP)germline mutations were identified in 62 patients,accounting for 7.6%(147/1,923)of all patients.MSH2 and APC was the most mutated gene in the Lynch syndrome and non-Lynch syndrome groups,respectively.Patients with P/LP mutations had a significantly higher ratio of microsatellite instability,highly deficient mismatch repair,family history of CRC,and lower age.The somatic mutational landscape revealed a significantly higher mutational frequency in the P group and a trend toward higher copy number variations in the non-P group.The Lynch syndrome group had a significantly higher mutational frequency and tumor mutational burden than the nonLynch syndrome group.Clustering analysis revealed that the Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Population risk analysis indicated that the overall odds ratio was 11.13(95%CI:8.289–15.44)for the P group and 20.68(95%CI:12.89–33.18)for the LP group.Conclusions:Distinct features were revealed in Chinese patients with CRC with germline mutations.The Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Patients with P/LP germline mutations exhibited higher CRC risk.

取向ZnO/Cu2O纳米异质结阵列的制备及光电特性研究

采用电化学沉积法制备了取向ZnO/Cu2O异质结阵列。通过FESEM、XRD、XPS、PL、IV特性测试等手段对形成的纳米异质结的形貌、晶体结构、化学成份、光致发光、IV特性和光电转换特性等进行了分析讨论。结果表明,沉积时间及沉积电压是影响制备高质量ZnO/Cu2O核壳异质结阵列的关键因素。异质结的Cu2O包覆层厚度约为15~25 nm,主要由单晶纳米晶粒构成,晶粒细致。测试发现,相对于纯ZnO纳米线阵列,ZnO/Cu2O异质结阵列的紫光发光峰强度有所减弱,绿光峰强度有所增强,且绿光峰的中心峰位还出现了20~30 nm的红移现象。同时,ZnO/Cu2O异质结阵列还表现出了较好的光电响应特性。

Black Phosphorus: An Effective Feedstock for the Synthesis of Phosphorus-Based Chemicals

We propose and demonstrate the novel concept of synthesizing organophosphorus compounds directly from black phosphorus(BP)nanoparticles as the feedstock.Compounds such as alkyl phosphines,alkyl phosphine oxides,phosphine sulfide,and hexafluorophosphate anion are prepared with good isolation yields under mild conditions.Selective synthesis of primary,secondary,and tertiary organophosphorus compounds is also demonstrated utilizing this one-pot approach.Reaction mechanisms are proposed and discussed.Compared with traditional white phosphorus(P 4)-based methods,the new synthetic concept and process utilizing elemental phosphorus are more efficient and environmentally friendly.

Large-scale identification of expression quantitative trait loci in Arabidopsis reveals novel candidate regulators of immune responses and other processes

The extensive phenotypic diversity within natural populations of Arabidopsis is associated with differences in gene expression.Transcript levels can be considered as in-heritable quantitative traits,and used to map expression quantitative trait loci(eQTL)in genome-wide association studies(GWASs).In order to identify putative genetic de-terminants for variations in gene expression,we used pub-licly available genomic and transcript variation data from 665 Arabidopsis accessions and applied the single nucleotide polymorphism-set(Sequence)Kernel Association Test(SKAT)method for the identification of eQTL.Moreover,we used the penalized orthogonal-components regression(POCRE)method to increase the power of statistical tests.Then,gene annotations were used as test units to identify genes that are associated with natural variations in transcript accumulation,which correspond to candidate regulators,some of which may have a broad impact on gene ex-pression.Besides increasing the chances to identify real as-sociations,the analysis using POCRE and SKAT significantly reduced the computational cost required to analyze large datasets.As a proof of concept,we used this approach to identify eQTL that represent novel candidate regulators of immune responses.The versatility of this approach allows its application to any process that is subjected to natural var-iation among Arabidopsis accessions.