Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra...Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated.展开更多
Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characterist...Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characteristics are investigated to identify key factors governing sweet spots.Siliceous shales with good preservation conditions in the Fuling Field exhibit large thickness,high TOC content and thin-section porosity(TSP),and well-developed OM macropores,thus high initial production and estimated ultimate recovery(EUR).Thin carbonate-containing siliceous shales with good preservation conditions in the Weirong Field feature medium-to-high TOC and well-developed OM macropores but low TSP,leading to high initial production but low EUR.Siliceous shales with poor preservation conditions in the Wulong Field are characterized by large thickness,high TOC,low TSP and poorly-developed OM macropores,causing low initial production and EUR.Both sedimentary and preservation conditions are intrinsic decisive factors of sweet spots,as they control the mineral composition,TOC,and OM macropore development.Deep-water shales in transgressive systems tracts(TSTs)exhibit better-developed OM macropores and greater TOC compared to highstand systems tracts(HSTs).OM macropores are most prevalent in siliceous shales,followed by carbonate-containing siliceous shales and then argillaceous shales.Furthermore,good preservation conditions are conducive to retain OM macropores with low pore aspect ratio(PAR).Comparison among the three fields shows that high-TOC silicious shales with good preservation conditions are the highest in TSP and EUR.Therefore,organic richness,lithofacies,and preservation conditions are the major factors which determine OM pore development,governing the sweet spots of the Wufeng-Longmaxi shales.展开更多
【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。...【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。【方法】用生物信息学方法对枸杞SWEET基因(LbaSWEETs)进行全基因组鉴定,并用已发表的转录数据分析LbaSWEETs在果实发育时期的基因表达情况。【结果】枸杞SWEET基因家族共有37个成员,随机分布于10条染色体上,分别编码152~621个氨基酸,蛋白质分子质量为16.87~69.97 kD,等电点为4.96~9.86。亚细胞定位预测位于叶绿体或质膜,大多数含有7个跨膜螺旋。系统进化分析发现,37个LbaSWEETs蛋白可分为4个亚群,每个亚群的基因结构和保守基序组成相似。启动子元件分析表明:Lba-SWEETs基因启动子富含大量激素响应、逆境胁迫和生长发育响应元件。转录组数据和qRT-PCR分析表明:LbaSWEET9和LbaSWEET29基因表达量随果实成熟呈现显著增加。相关性分析结果表明,LbaSWEET9和LbaSWEET29基因表达量与果糖含量呈显著正相关。【结论】LbaSWEET9和LbaSWEET29基因是果糖积累的关键基因。展开更多
SWEET(Sugars will eventually be exported transporters)是近年来在植物中发现的一组糖转运蛋白,在植物生长、发育和非生物及生物胁迫响应等多种生理过程中发挥着重要作用。本研究利用生物信息学方法对猕猴桃(Actinidia chinensis Pla...SWEET(Sugars will eventually be exported transporters)是近年来在植物中发现的一组糖转运蛋白,在植物生长、发育和非生物及生物胁迫响应等多种生理过程中发挥着重要作用。本研究利用生物信息学方法对猕猴桃(Actinidia chinensis Planch.)AcSWEET基因家族进行了鉴定,共获得29个AcSWEET基因,并对其氨基酸数量、相对分子量、等电点、不稳定系数、亚细胞定位、亲水指数进行了分析。结果显示:29个基因编码的氨基酸数目为680~906个;分子量范围为7.531~101.266 kDa,等电点在6.95~9.90,多数蛋白为定位于细胞膜的疏水性蛋白,具有1~2个MtN3结构域或PQ-loop结构域。此外,AcSWEET基因的外显子数量在4~6个,系统进化分析结果表明猕猴桃AcSWEET基因家族被分为4个亚族,同一亚族基因具有相似的内含子、外显子以及保守基序。表达模式分析结果表明,这些基因在果实不同发育时期具有表达特异性。推测AcSWEET26、AcSWEET7、AcSWEET15和AcSWEET13可能参与猕猴桃的蔗糖转运和积累。展开更多
SWEET(sugars will eventually be exported transporter)是一类介导蔗糖或己糖通过顺浓度梯度被动扩散跨细胞膜转运的新型糖转运蛋白。植物SWEET蛋白包括7个跨膜结构域,其中包含2个MtN3/Saliva结构域,可分为4个进化分支。SWEET转运蛋...SWEET(sugars will eventually be exported transporter)是一类介导蔗糖或己糖通过顺浓度梯度被动扩散跨细胞膜转运的新型糖转运蛋白。植物SWEET蛋白包括7个跨膜结构域,其中包含2个MtN3/Saliva结构域,可分为4个进化分支。SWEET转运蛋白在多种生理和生化过程中发挥着关键作用,包括韧皮部装载、激素运输、营养和生殖生长等。结合当前SWEET转运蛋白的研究进展,重点总结了SWEET的发现、蛋白结构及其在糖转运中的生物学功能,指出目前植物SWEET基因研究面临的问题,并对未来SWEET蛋白的研究重点进行了展望:1)探究SWEET蛋白的底物识别机制;2)挖掘提高作物产量和品质的关键SWEET基因;3)利用SWEET基因编辑和磷酸化等策略改良作物产量和品质。展开更多
Unconventional oil and gas resources require petrophysical logs to answer the question of how best to optimize geological and engineering‘sweet spots'.Therefore,the establishment of a key well with comprehensive ...Unconventional oil and gas resources require petrophysical logs to answer the question of how best to optimize geological and engineering‘sweet spots'.Therefore,the establishment of a key well with comprehensive descriptions of lithology,reservoir properties,hydrocarbon-bearing properties,electronic well log responses,source rock properties,brittleness,and in situ stress magnitude and direction is important for the effective exploration and production of unconventional hydrocarbon resources.Cores,thin sections,scanning electron microscopy(SEM)and comprehensive well log suites are used to build a key well for the Permian Lucaogou Formation,Jimusar Sag of the Junggar Basin.The results show that there are three main types of lithologies,including siltstone,mudstone and dolostone.Lithologies can be predicted using the combination of conventional well and image logs.The pore spaces consist of interparticle pores,intragranular dissolution pores and micropores.Nuclear Magnetic Resonance(NMR)T_(2)components longer than 1.7 ms are superposed as effective porosity.Permeability is calculated using the Coates model from NMR T_(2)spectra.The ratio of T_(2)components>7.0 ms to T_(2)components>0.3 ms is used to calculate oil saturation.TOC is calculated using theΔlog R method.Brittleness index is calculated using Poisson-Young's method,ranging from 13.42%-70.53%.In situ stress direction is determined,and in situ stress magnitudes(maximum horizontal stress SH_(max),minimum horizontal stress Sh_(min),vertical stress S_(v))are calculated using density and sonic logs.The strike-slip stress type(SH_(max)>S_(v)>Sh_(min))is encountered.The key well which comprehensively includes the above seven properties is established.Geological and engineering(geomechanical)‘sweet spots'are then optimized from the key well by fully analyzing lithology,reservoir property,oilbearing potential,in situ stress magnitude and brittleness.It is hoped that the results support engineers'and geologists'decisions for the future exploitation of unconventional hydrocarbon resources.展开更多
植物SWEET(Sugars will eventually be exported transporter)基因家族是一类重要的糖转运蛋白,参与开花植物的花蜜合成。本研究以野生型和突变型滇水金凤(Impatiens uliginosa)为材料,基于课题组前期的花距转录组数据,通过筛选和RT-PC...植物SWEET(Sugars will eventually be exported transporter)基因家族是一类重要的糖转运蛋白,参与开花植物的花蜜合成。本研究以野生型和突变型滇水金凤(Impatiens uliginosa)为材料,基于课题组前期的花距转录组数据,通过筛选和RT-PCR技术克隆得到花蜜相关基因SWEET7和SWEET16,分别命名为IuSWEET7和IuSWEET16,其cDNA分别为741 bp和903 bp,分别编码246和300个氨基酸。生物信息学分析表明:IuSWEET7为疏水性不稳定蛋白,IuSWEET16为疏水性稳定蛋白,二者均含有2个典型的MtN3/saliv保守结构域;IuSWEET7和IuSWEET16基因的氨基酸序列与杜鹃花(KAG5539487.1)、一串红(XP_042052415.1)等植物同源序列的相似性均在54.15%~71.48%;系统进化分析表明,IuSWEET7和IuSWEET16处于两个不同分支。qRT-PCR分析表明两个基因在野生型和突变型滇水金凤花距的3个时期中均有表达,且在不同部位中表达模式不同。其中IuSWEET7基因在野生型滇水金凤中其表达量从花苞期至盛花期逐渐上升;在突变型2距和3距中其表达量从花苞期至盛花期先上升后下降,且在始花期表达量最高;而IuSWEET16基因在野生型和突变型3距中其表达量从花苞期至盛花期均逐渐上升,但在突变型2距中其表达量从花苞期至盛花期先上升后下降,也在始花期时达到最高。展开更多
【目的】挖掘参与油茶糖代谢及逆境响应的糖外排转运子(sugars will eventually be exported transporters,SWEETs)。【方法】利用生物信息学方法分析油茶SWEETs家族的基因结构、蛋白基序、染色体定位、共线性关系、启动子区顺式作用元...【目的】挖掘参与油茶糖代谢及逆境响应的糖外排转运子(sugars will eventually be exported transporters,SWEETs)。【方法】利用生物信息学方法分析油茶SWEETs家族的基因结构、蛋白基序、染色体定位、共线性关系、启动子区顺式作用元件及上游调控因子等,并利用RT-qPCR分析CoSWEETs在不同时期、不同组织及不同逆境胁迫下的基因表达情况。【结果】从油茶中鉴定得到14个CoSWEETs基因,不均匀分布于10条染色体上,不同成员间内含子-外显子数目存在差异。根据系统进化关系,14个CoSWEETs可分为 4个分支,均具有1-2个MtN3 保守结构域,同一分支具有相似的基因结构和基序。根据启动子顺式作用元件和上游转录因子预测的分析结果,CoSWEETs启动子中含有多个与生长发育、植物激素和应激相关的调节元件,其表达可能受到ERF、DOF、BBR-BPC、MYB等转录因子的调控。RT-qPCR分析表明大部分CoSWEETs成员在果实和根中高表达,在种子中的表达水平与发育时期相关,并根据低温、高盐和干旱等非生物胁迫下CoSWEETs的表达模式挖掘出CoSWEET1、CoSWEET2、CoSWEET17等响应油茶低温、干旱或高盐胁迫的基因。【结论】CoSWEET基因的表达受到多种激素及转录因子调控,并在油茶种子发育与逆境胁迫响应中发挥重要作用。展开更多
The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”....The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”. To accurately identify and optimize the favorable sweet spots of shale oil in Qingshankou Formation, Songliao Basin, the original logging data were preprocessed in this paper. Then the thin mud shale interlayer of Qingshankou Formation was identified effectively by using the processed logging data. Based on the artificial neural network method, the mineral content of mud shale in Qingshankou Formation was predicted. The lithofacies were identified according to the mineral and TOC content. Finally, a three-dimensional (3-D) model of total organic carbon (TOC), vitrinite reflectance (Ro), mineral content, and rock of Qingshankou Formation in Songliao Basin was established to evaluate and predict the favorable sweet spots of shale oil in the study area. The results show that there are a lot of calcareous and siliceous thin interlayers in Qingshankou Formation, and TOC content is generally between 2% and 3%. Ro is the highest in Gulong sag, followed by Sanzhao sag. The lithofacies mainly consists of felsic shale and mixed shale, mainly in the first member of Qingshankou Formation. Comprehensive analysis shows that shale oil development potential is enormous in the eastern part of Sanzhao Sag and the northern part of Gulong Sag.展开更多
The pancreas is neither part of the five Zang organs(五脏) nor the six Fu organs(六腑).Thus,it has received little attention in Chinese medical literature.In the late 19th century,medical missionaries in China started...The pancreas is neither part of the five Zang organs(五脏) nor the six Fu organs(六腑).Thus,it has received little attention in Chinese medical literature.In the late 19th century,medical missionaries in China started translating and introducing anatomical and physiological knowledge about the pancreas.As for the word pancreas,an early and influential translation was “sweet meat”(甜肉),proposed by Benjamin Hobson(合信).The translation “sweet meat” is not faithful to the original meaning of “pancreas”,but is a term coined by Hobson based on his personal habits,and the word “sweet” appeared by chance.However,in the decades since the term “sweet meat” became popular,Chinese medicine practitioners,such as Tang Zonghai(唐宗海),reinterpreted it by drawing new medical illustrations for “sweet meat” and giving new connotations to the word “sweet”.This discussion and interpretation of “sweet meat” in modern China,particularly among Chinese medicine professionals,is not only a dissemination and interpretation of the knowledge of “pancreas”,but also a construction of knowledge around the term “sweet meat”.展开更多
SWEET(Sugars will eventually be exported transporter)蛋白是一类新型糖转运蛋白。本研究基于扁蓿豆(Medicago ruthenica)基因组对MrSWEET基因家族进行了鉴定和生物信息学分析,并通过qPCR初步分析MrSWEET在干旱和寒冷环境下的表达模...SWEET(Sugars will eventually be exported transporter)蛋白是一类新型糖转运蛋白。本研究基于扁蓿豆(Medicago ruthenica)基因组对MrSWEET基因家族进行了鉴定和生物信息学分析,并通过qPCR初步分析MrSWEET在干旱和寒冷环境下的表达模式,以期深入探究扁蓿豆SWEET基因家族在非生物胁迫中的作用。结果表明,扁蓿豆SWEET糖转运蛋白家族共有18个成员,都具有典型的MtN3_saliva/PQ-Loop结构域。系统发育分析表明,其可分为4个进化枝,其中CladeⅠ包括MrSWEET1a、-1b、-2a、-2b、-3a、-3b;CladeⅡ包括MrSWEET4~6;CladeⅢ包括MrSWEET9~15,MrSWEET16~17属于CladeⅣ。所有的MrSWEET成员都含有Motif 1、3、4、5,可能与糖转运蛋白的功能有关。MrSWEET基因启动子区域含有多个与光响应、激素响应和非生物胁迫以及植物生长发育有关的功能元件。在干旱(15%PEG6000)和寒冷(4℃)胁迫下,扁蓿豆根部的MrSWEET基因表达水平相对高于叶片,且根部大多数基因在干旱和寒冷胁迫处理6、12 h时表达量最高;干旱处理下,根部的MrSWEET1a和MrSWEET16相对表达量在3、6、12、24 h和7 d时均高于对照,寒冷处理下根部的MrSWEET16表达量以及处理7 d的MrSWEET1a表达量高于对照,说明其可能参与调控扁蓿豆对干旱和寒冷胁迫的响应。展开更多
At the beginning of the 16th century,Paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and cells.The brain and its glial and neuronal cell...At the beginning of the 16th century,Paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and cells.The brain and its glial and neuronal cells are no exception.Even small compounds that are essential for the life of brain cells can become truly toxic when overdosed.展开更多
基金financially supported by the CNPC Prospective Basic Science and Technology Special Project(2023ZZ08)the Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(2020CX050103)。
文摘Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated.
文摘Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characteristics are investigated to identify key factors governing sweet spots.Siliceous shales with good preservation conditions in the Fuling Field exhibit large thickness,high TOC content and thin-section porosity(TSP),and well-developed OM macropores,thus high initial production and estimated ultimate recovery(EUR).Thin carbonate-containing siliceous shales with good preservation conditions in the Weirong Field feature medium-to-high TOC and well-developed OM macropores but low TSP,leading to high initial production but low EUR.Siliceous shales with poor preservation conditions in the Wulong Field are characterized by large thickness,high TOC,low TSP and poorly-developed OM macropores,causing low initial production and EUR.Both sedimentary and preservation conditions are intrinsic decisive factors of sweet spots,as they control the mineral composition,TOC,and OM macropore development.Deep-water shales in transgressive systems tracts(TSTs)exhibit better-developed OM macropores and greater TOC compared to highstand systems tracts(HSTs).OM macropores are most prevalent in siliceous shales,followed by carbonate-containing siliceous shales and then argillaceous shales.Furthermore,good preservation conditions are conducive to retain OM macropores with low pore aspect ratio(PAR).Comparison among the three fields shows that high-TOC silicious shales with good preservation conditions are the highest in TSP and EUR.Therefore,organic richness,lithofacies,and preservation conditions are the major factors which determine OM pore development,governing the sweet spots of the Wufeng-Longmaxi shales.
文摘【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。【方法】用生物信息学方法对枸杞SWEET基因(LbaSWEETs)进行全基因组鉴定,并用已发表的转录数据分析LbaSWEETs在果实发育时期的基因表达情况。【结果】枸杞SWEET基因家族共有37个成员,随机分布于10条染色体上,分别编码152~621个氨基酸,蛋白质分子质量为16.87~69.97 kD,等电点为4.96~9.86。亚细胞定位预测位于叶绿体或质膜,大多数含有7个跨膜螺旋。系统进化分析发现,37个LbaSWEETs蛋白可分为4个亚群,每个亚群的基因结构和保守基序组成相似。启动子元件分析表明:Lba-SWEETs基因启动子富含大量激素响应、逆境胁迫和生长发育响应元件。转录组数据和qRT-PCR分析表明:LbaSWEET9和LbaSWEET29基因表达量随果实成熟呈现显著增加。相关性分析结果表明,LbaSWEET9和LbaSWEET29基因表达量与果糖含量呈显著正相关。【结论】LbaSWEET9和LbaSWEET29基因是果糖积累的关键基因。
文摘非霍奇金淋巴瘤(non-Hodgkin lymphoma,NHL)是临床常见的肿瘤类型,临床表现多样,确诊依赖组织活检,根据病灶起源可以分为结内和结外淋巴瘤。原发性胃肠淋巴瘤是结外淋巴瘤的常见部位,可以累及胃、小肠、结肠等,其中约50%~60%发生在胃部,病理类型以黏膜相关淋巴组织淋巴瘤和弥漫大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)为主[1~3]。
文摘SWEET(Sugars will eventually be exported transporters)是近年来在植物中发现的一组糖转运蛋白,在植物生长、发育和非生物及生物胁迫响应等多种生理过程中发挥着重要作用。本研究利用生物信息学方法对猕猴桃(Actinidia chinensis Planch.)AcSWEET基因家族进行了鉴定,共获得29个AcSWEET基因,并对其氨基酸数量、相对分子量、等电点、不稳定系数、亚细胞定位、亲水指数进行了分析。结果显示:29个基因编码的氨基酸数目为680~906个;分子量范围为7.531~101.266 kDa,等电点在6.95~9.90,多数蛋白为定位于细胞膜的疏水性蛋白,具有1~2个MtN3结构域或PQ-loop结构域。此外,AcSWEET基因的外显子数量在4~6个,系统进化分析结果表明猕猴桃AcSWEET基因家族被分为4个亚族,同一亚族基因具有相似的内含子、外显子以及保守基序。表达模式分析结果表明,这些基因在果实不同发育时期具有表达特异性。推测AcSWEET26、AcSWEET7、AcSWEET15和AcSWEET13可能参与猕猴桃的蔗糖转运和积累。
文摘SWEET(sugars will eventually be exported transporter)是一类介导蔗糖或己糖通过顺浓度梯度被动扩散跨细胞膜转运的新型糖转运蛋白。植物SWEET蛋白包括7个跨膜结构域,其中包含2个MtN3/Saliva结构域,可分为4个进化分支。SWEET转运蛋白在多种生理和生化过程中发挥着关键作用,包括韧皮部装载、激素运输、营养和生殖生长等。结合当前SWEET转运蛋白的研究进展,重点总结了SWEET的发现、蛋白结构及其在糖转运中的生物学功能,指出目前植物SWEET基因研究面临的问题,并对未来SWEET蛋白的研究重点进行了展望:1)探究SWEET蛋白的底物识别机制;2)挖掘提高作物产量和品质的关键SWEET基因;3)利用SWEET基因编辑和磷酸化等策略改良作物产量和品质。
基金financially supported by the National Natural Science Foundation of China(Grant Nos.42002133,42072150)the Strategic Cooperation Project of Petro China and CUPB(Grant No.ZLZX2020-01-06-01)the Science Foundation of China University of Petroleum,Beijing(Grant No.2462021YXZZ003)。
文摘Unconventional oil and gas resources require petrophysical logs to answer the question of how best to optimize geological and engineering‘sweet spots'.Therefore,the establishment of a key well with comprehensive descriptions of lithology,reservoir properties,hydrocarbon-bearing properties,electronic well log responses,source rock properties,brittleness,and in situ stress magnitude and direction is important for the effective exploration and production of unconventional hydrocarbon resources.Cores,thin sections,scanning electron microscopy(SEM)and comprehensive well log suites are used to build a key well for the Permian Lucaogou Formation,Jimusar Sag of the Junggar Basin.The results show that there are three main types of lithologies,including siltstone,mudstone and dolostone.Lithologies can be predicted using the combination of conventional well and image logs.The pore spaces consist of interparticle pores,intragranular dissolution pores and micropores.Nuclear Magnetic Resonance(NMR)T_(2)components longer than 1.7 ms are superposed as effective porosity.Permeability is calculated using the Coates model from NMR T_(2)spectra.The ratio of T_(2)components>7.0 ms to T_(2)components>0.3 ms is used to calculate oil saturation.TOC is calculated using theΔlog R method.Brittleness index is calculated using Poisson-Young's method,ranging from 13.42%-70.53%.In situ stress direction is determined,and in situ stress magnitudes(maximum horizontal stress SH_(max),minimum horizontal stress Sh_(min),vertical stress S_(v))are calculated using density and sonic logs.The strike-slip stress type(SH_(max)>S_(v)>Sh_(min))is encountered.The key well which comprehensively includes the above seven properties is established.Geological and engineering(geomechanical)‘sweet spots'are then optimized from the key well by fully analyzing lithology,reservoir property,oilbearing potential,in situ stress magnitude and brittleness.It is hoped that the results support engineers'and geologists'decisions for the future exploitation of unconventional hydrocarbon resources.
文摘植物SWEET(Sugars will eventually be exported transporter)基因家族是一类重要的糖转运蛋白,参与开花植物的花蜜合成。本研究以野生型和突变型滇水金凤(Impatiens uliginosa)为材料,基于课题组前期的花距转录组数据,通过筛选和RT-PCR技术克隆得到花蜜相关基因SWEET7和SWEET16,分别命名为IuSWEET7和IuSWEET16,其cDNA分别为741 bp和903 bp,分别编码246和300个氨基酸。生物信息学分析表明:IuSWEET7为疏水性不稳定蛋白,IuSWEET16为疏水性稳定蛋白,二者均含有2个典型的MtN3/saliv保守结构域;IuSWEET7和IuSWEET16基因的氨基酸序列与杜鹃花(KAG5539487.1)、一串红(XP_042052415.1)等植物同源序列的相似性均在54.15%~71.48%;系统进化分析表明,IuSWEET7和IuSWEET16处于两个不同分支。qRT-PCR分析表明两个基因在野生型和突变型滇水金凤花距的3个时期中均有表达,且在不同部位中表达模式不同。其中IuSWEET7基因在野生型滇水金凤中其表达量从花苞期至盛花期逐渐上升;在突变型2距和3距中其表达量从花苞期至盛花期先上升后下降,且在始花期表达量最高;而IuSWEET16基因在野生型和突变型3距中其表达量从花苞期至盛花期均逐渐上升,但在突变型2距中其表达量从花苞期至盛花期先上升后下降,也在始花期时达到最高。
文摘【目的】挖掘参与油茶糖代谢及逆境响应的糖外排转运子(sugars will eventually be exported transporters,SWEETs)。【方法】利用生物信息学方法分析油茶SWEETs家族的基因结构、蛋白基序、染色体定位、共线性关系、启动子区顺式作用元件及上游调控因子等,并利用RT-qPCR分析CoSWEETs在不同时期、不同组织及不同逆境胁迫下的基因表达情况。【结果】从油茶中鉴定得到14个CoSWEETs基因,不均匀分布于10条染色体上,不同成员间内含子-外显子数目存在差异。根据系统进化关系,14个CoSWEETs可分为 4个分支,均具有1-2个MtN3 保守结构域,同一分支具有相似的基因结构和基序。根据启动子顺式作用元件和上游转录因子预测的分析结果,CoSWEETs启动子中含有多个与生长发育、植物激素和应激相关的调节元件,其表达可能受到ERF、DOF、BBR-BPC、MYB等转录因子的调控。RT-qPCR分析表明大部分CoSWEETs成员在果实和根中高表达,在种子中的表达水平与发育时期相关,并根据低温、高盐和干旱等非生物胁迫下CoSWEETs的表达模式挖掘出CoSWEET1、CoSWEET2、CoSWEET17等响应油茶低温、干旱或高盐胁迫的基因。【结论】CoSWEET基因的表达受到多种激素及转录因子调控,并在油茶种子发育与逆境胁迫响应中发挥重要作用。
文摘The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”. To accurately identify and optimize the favorable sweet spots of shale oil in Qingshankou Formation, Songliao Basin, the original logging data were preprocessed in this paper. Then the thin mud shale interlayer of Qingshankou Formation was identified effectively by using the processed logging data. Based on the artificial neural network method, the mineral content of mud shale in Qingshankou Formation was predicted. The lithofacies were identified according to the mineral and TOC content. Finally, a three-dimensional (3-D) model of total organic carbon (TOC), vitrinite reflectance (Ro), mineral content, and rock of Qingshankou Formation in Songliao Basin was established to evaluate and predict the favorable sweet spots of shale oil in the study area. The results show that there are a lot of calcareous and siliceous thin interlayers in Qingshankou Formation, and TOC content is generally between 2% and 3%. Ro is the highest in Gulong sag, followed by Sanzhao sag. The lithofacies mainly consists of felsic shale and mixed shale, mainly in the first member of Qingshankou Formation. Comprehensive analysis shows that shale oil development potential is enormous in the eastern part of Sanzhao Sag and the northern part of Gulong Sag.
基金financed by the grant from the Youth Fund for Humanities and Social Sciences Research of the Ministry of Education (No. 19YJCZH040)。
文摘The pancreas is neither part of the five Zang organs(五脏) nor the six Fu organs(六腑).Thus,it has received little attention in Chinese medical literature.In the late 19th century,medical missionaries in China started translating and introducing anatomical and physiological knowledge about the pancreas.As for the word pancreas,an early and influential translation was “sweet meat”(甜肉),proposed by Benjamin Hobson(合信).The translation “sweet meat” is not faithful to the original meaning of “pancreas”,but is a term coined by Hobson based on his personal habits,and the word “sweet” appeared by chance.However,in the decades since the term “sweet meat” became popular,Chinese medicine practitioners,such as Tang Zonghai(唐宗海),reinterpreted it by drawing new medical illustrations for “sweet meat” and giving new connotations to the word “sweet”.This discussion and interpretation of “sweet meat” in modern China,particularly among Chinese medicine professionals,is not only a dissemination and interpretation of the knowledge of “pancreas”,but also a construction of knowledge around the term “sweet meat”.
文摘SWEET(Sugars will eventually be exported transporter)蛋白是一类新型糖转运蛋白。本研究基于扁蓿豆(Medicago ruthenica)基因组对MrSWEET基因家族进行了鉴定和生物信息学分析,并通过qPCR初步分析MrSWEET在干旱和寒冷环境下的表达模式,以期深入探究扁蓿豆SWEET基因家族在非生物胁迫中的作用。结果表明,扁蓿豆SWEET糖转运蛋白家族共有18个成员,都具有典型的MtN3_saliva/PQ-Loop结构域。系统发育分析表明,其可分为4个进化枝,其中CladeⅠ包括MrSWEET1a、-1b、-2a、-2b、-3a、-3b;CladeⅡ包括MrSWEET4~6;CladeⅢ包括MrSWEET9~15,MrSWEET16~17属于CladeⅣ。所有的MrSWEET成员都含有Motif 1、3、4、5,可能与糖转运蛋白的功能有关。MrSWEET基因启动子区域含有多个与光响应、激素响应和非生物胁迫以及植物生长发育有关的功能元件。在干旱(15%PEG6000)和寒冷(4℃)胁迫下,扁蓿豆根部的MrSWEET基因表达水平相对高于叶片,且根部大多数基因在干旱和寒冷胁迫处理6、12 h时表达量最高;干旱处理下,根部的MrSWEET1a和MrSWEET16相对表达量在3、6、12、24 h和7 d时均高于对照,寒冷处理下根部的MrSWEET16表达量以及处理7 d的MrSWEET1a表达量高于对照,说明其可能参与调控扁蓿豆对干旱和寒冷胁迫的响应。
文摘At the beginning of the 16th century,Paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and cells.The brain and its glial and neuronal cells are no exception.Even small compounds that are essential for the life of brain cells can become truly toxic when overdosed.