The present work reports the first solid phase synthesis of biologically interesting D-threo-l-phenyl-2- decanoylamino-3-morpholino-l-propanol （D-threo-PDMP） derivatives. This synthetic strategy includes facile prep...The present work reports the first solid phase synthesis of biologically interesting D-threo-l-phenyl-2- decanoylamino-3-morpholino-l-propanol （D-threo-PDMP） derivatives. This synthetic strategy includes facile preparation of versatile azido intermediate （5） in a relatively short sequence and the subsequent derivatization of 5, which led to a series of sulfonamide, urea and heterocycle substituted PDMP analogs （10 and 10＇）. With this method, a 5280-member compound library has been successfully built by IRORI Nanokan system.展开更多
Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fi...Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fiber cells.However,their function in cotton fiber cell development and its action mechanism is unclear.Through cotton genetic transformation and chemistry biological approach,we identified the function and action mechanism of the glucosylceramide synthase gene GhGCS1 and its product glucosylceramide(GluCer)in cotton fiber growth.GhGCS1 was preferentially expressed at the stage of fiber elongation and localized in the endoplasmic reticulum.Overexpression of GhGCS1 promoted GluCer synthesis and fiber elongation,which was consistent with the exogenous application of GluCer(FA-C22)(containing very long-acyl-chain fatty acid)to cotton fiber in ovule culture system in vitro.Contrarily,suppressing GhGCS1 expression inhibited GluCer synthesis and fiber elongation,which was similar as the exogenous application of GluCer synthesis inhibitor,PDMP.Transcriptome analysis revealed that the fiber elongation regulated by GhGCS1 was associated with brassinosteroid(BR)synthesis and signaling related gene expression.Meanwhile,we detected the BL content of control and transgenic fiber cells.The BL content significantly increased and decreased in up-and down-regulated transgenic fibers when compared with control fibers,respectively.Furthermore,we found that PDMP treatment blocked BR synthesis and signal transduction,while exogenous application of GluCer could enhance BR synthesis and signaling.Overall,our results revealed that GhGCS1 and GluCer regulated cotton fiber elongation by influencing BR synthesis and signaling.Our study shed a novel insight on regulatory mechanism of cotton fiber elongation and provides theoretical support,genetic resources and novel transgenic materials for improvement of crop quality.展开更多
In this paper we consider a risk model with two kinds of claims, whose claims number processes are Poisson process and ordinary renewal process respectively. For this model, the surplus process is not Markovian, howev...In this paper we consider a risk model with two kinds of claims, whose claims number processes are Poisson process and ordinary renewal process respectively. For this model, the surplus process is not Markovian, however, it can be Markovianized by introducing a supplementary process, We prove the Markov property of the related vector processes. Because such obtained processes belong to the class of the so-called piecewise-deterministic Markov process, the extended infinitesimal generator is derived, exponential martingale for the risk process is studied. The exponential bound of ruin probability in iafinite time horizon is obtained.展开更多
文摘The present work reports the first solid phase synthesis of biologically interesting D-threo-l-phenyl-2- decanoylamino-3-morpholino-l-propanol （D-threo-PDMP） derivatives. This synthetic strategy includes facile preparation of versatile azido intermediate （5） in a relatively short sequence and the subsequent derivatization of 5, which led to a series of sulfonamide, urea and heterocycle substituted PDMP analogs （10 and 10＇）. With this method, a 5280-member compound library has been successfully built by IRORI Nanokan system.
基金funded by the National Natural Science Foundation of China(32372114,31971984)the Special Fund for Youth Team of the Southwest Universities(SWU-XJPY202306)+1 种基金the Chongqing Graduate Scientific Research Innovation Project(CYS23239)the Genetically Modified Organisms Breeding Major Project of China(2018ZX0800921B)。
文摘Sphingolipids are not only a pivotal component of membranes but also act as bioactive molecules.Cotton fiber is one of the longest plant cells and sphingolipids are closely associated with the development of cotton fiber cells.However,their function in cotton fiber cell development and its action mechanism is unclear.Through cotton genetic transformation and chemistry biological approach,we identified the function and action mechanism of the glucosylceramide synthase gene GhGCS1 and its product glucosylceramide(GluCer)in cotton fiber growth.GhGCS1 was preferentially expressed at the stage of fiber elongation and localized in the endoplasmic reticulum.Overexpression of GhGCS1 promoted GluCer synthesis and fiber elongation,which was consistent with the exogenous application of GluCer(FA-C22)(containing very long-acyl-chain fatty acid)to cotton fiber in ovule culture system in vitro.Contrarily,suppressing GhGCS1 expression inhibited GluCer synthesis and fiber elongation,which was similar as the exogenous application of GluCer synthesis inhibitor,PDMP.Transcriptome analysis revealed that the fiber elongation regulated by GhGCS1 was associated with brassinosteroid(BR)synthesis and signaling related gene expression.Meanwhile,we detected the BL content of control and transgenic fiber cells.The BL content significantly increased and decreased in up-and down-regulated transgenic fibers when compared with control fibers,respectively.Furthermore,we found that PDMP treatment blocked BR synthesis and signal transduction,while exogenous application of GluCer could enhance BR synthesis and signaling.Overall,our results revealed that GhGCS1 and GluCer regulated cotton fiber elongation by influencing BR synthesis and signaling.Our study shed a novel insight on regulatory mechanism of cotton fiber elongation and provides theoretical support,genetic resources and novel transgenic materials for improvement of crop quality.
基金Supported by the National Natural Science Foundation of China (Grant No. 10871102)National Basic Research Program of China (973 Program) 2007CB814905
文摘In this paper we consider a risk model with two kinds of claims, whose claims number processes are Poisson process and ordinary renewal process respectively. For this model, the surplus process is not Markovian, however, it can be Markovianized by introducing a supplementary process, We prove the Markov property of the related vector processes. Because such obtained processes belong to the class of the so-called piecewise-deterministic Markov process, the extended infinitesimal generator is derived, exponential martingale for the risk process is studied. The exponential bound of ruin probability in iafinite time horizon is obtained.
