Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the...Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.展开更多
Protein phosphorylation plays an important role in physiological processes, such as muscle contraction. Phospho-specific antibodies have become powerful tools to study these processes. Cardiac myosin binding protein-C...Protein phosphorylation plays an important role in physiological processes, such as muscle contraction. Phospho-specific antibodies have become powerful tools to study these processes. Cardiac myosin binding protein-C (cMyBP-C) is one of the proteins that make up the contractile apparatus of cardiomyocytes. Phosphorylation of cMyBP-C is essential for normal cardiac function, since dephosphorylation of this protein leads to its degradation and has been associated with cardiomyopathy. One of the upstream kinases, which phosphorylate cMyBP-C, is protein kinase D (PKD). While studying the role of PKD in cMyBP-C phosphorylation, we tried to analyze phosphorylation of PKD with a phospho-specific PKD-Ser744/748 antibody. Contrary to the expected 115 kDa, a signal was found for a 150-kDa protein. By MALDI-TOF mass spectrometry, we identified this protein to be cMyBP-C. These data were confirmed by immunostaining using the p-PKD-Ser744/748 antibody, which displayed a striated pattern similar to the one observed for a regular cMyBP-C antibody. To our knowledge there are no antibodies commercially available for phosphorylated cMyBP-C. Thus, the p-PKD-Ser744/748 antibody can accelerate research into the role of cMyBP-C phosphorylation in cardiomyocytes.展开更多
Nucleosides were phosphorylated with different N- (O, O-diisopropyl) phosphoryl amino acids to give nucleoside mono phosphates in aqueous solution. 2', 3', and 5'-isomers had been confirmed by comparison w...Nucleosides were phosphorylated with different N- (O, O-diisopropyl) phosphoryl amino acids to give nucleoside mono phosphates in aqueous solution. 2', 3', and 5'-isomers had been confirmed by comparison with authentic samples on the basis of HPLC analysis. The conversion percentage of nucleoside indicated that N- (O, O-diisopropyl) phosphoryl aspartic acid reacted with adenosine and guanosine at a much higher rate than other kinds of N- phosphoryl amino acids. while phosphorylation of cytidine and uridine was relatively easy by using N- (O, O-diisopropyl) phosphoryl threonine. The result could give some clue to the prebiotic code origin of nucleic acid and protein.展开更多
It has been widely recognized that loess has a low stability and permeability,and it is susceptible to a sudden decrease in total volume or collapse upon wetting.When the railway subgrade was under the dynamic trainlo...It has been widely recognized that loess has a low stability and permeability,and it is susceptible to a sudden decrease in total volume or collapse upon wetting.When the railway subgrade was under the dynamic trainload,the loess subgrade was prone to instability and liquefaction.loess is higher than that of the cement modified loess,but lower than that of the MPG modified loess.However,the coefficient of permeability for the MPGcement modified loess has an opposite result,and the MPG-cement modified loess specimens have the best frost resistance.In addition,the mechanism of MPG-Bao Zhong railway is a key railway for Guyuan city,in Ningxia province of China,which is an important city of the Belt and Road.Due to the influence of largearea flood irrigation on the farmland,the subgrade had a degree of settlement.The settlement had not been alleviated after three treatments,which seriously affected the safety of the train.For this reason,cement,Modified Phospho Gypsum(MPG)and MPGcement were used to reinforce the subgrade loess,and the unconfined compressive strength test,permeability test and freeze-thaw cycle test were carried out.Then the compressive strength,impermeability and frost resistance of the three were analyzed and compared.The results indicate that the compressive strength of the MPG-cement modified cement modified loess is discussed.It is found that cement and MPG have two hydration reactions with water in loess.Ettringite,the hydration reaction product,which not only fills the pores,restricts the movement of the soil particles,but also acts as a connecting soil particle in the soil particles.Therefore,the strength of the modified loess continues to increase,and the physical properties of the modified loess are improved.展开更多
Objective:Diffuse large B-cell lymphoma(DLBCL)is an aggressive type of non-Hodgkin lymphoma.Due to its genetic heterogeneity and abnormal metabolism,many DLBCL patients have a poor prognosis.This study investigated th...Objective:Diffuse large B-cell lymphoma(DLBCL)is an aggressive type of non-Hodgkin lymphoma.Due to its genetic heterogeneity and abnormal metabolism,many DLBCL patients have a poor prognosis.This study investigated the key metabolism-related genes and potential mechanisms.Methods:Differentially expressed genes,differentially expressed transcription factors(TFs),and differentially expressed metabolism-related genes(DEMRGs)of glucose and lipid metabolic processes were identified using the edgeR package.Key DEMRGs were screened by Lasso regression,and a prediction model was constructed.The cell type identification by estimating relative subsets of RNA transcripts algorithm was utilized to assess the fraction of immune cells,and Gene Set Enrichment Analysis was used to determine immune-related pathways.A regulatory network was constructed with significant co-expression interactions among TFs,DEMRGs,immune cells/pathways,and hallmark pathways.Results:A total of 1551 DEMRGs were identified.A prognostic model with a high applicability(area under the curve=0.921)was constructed with 13 DEMRGs.Tumorigenesis of DLBCL was highly related to the neutrophil count.Four DEMRGs(PRXL2AB,CCN1,DECR2 and PHOSPHO1)with 32 TF-DEMRG,36 DEMRG-pathway,14 DEMRG-immune-cell,9 DEMRG-immune-gene-set,and 67 DEMRG-protein-chip interactions were used to construct the regulatory network.Conclusion:We provided a prognostic prediction model based on 13 DEMRGs for DLBCL.We found that phosphatase,orphan 1(PHOSPHO1)is positively regulated by regulatory factor X5(RFX5)and mediates MYC proto-oncogene(MYC)targeting the V2 pathway and neutrophils.展开更多
The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl...The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl 2-perfluoroalkynoates 2a-c in the presence of K2CO3 at room temperature gives two adducts, (E)-methyl 3-per-fluoroalkyl-4-( 3-carboethoxy-2-furanyl )-2-triphenylphosphoranylidene-3-butenoates 3a-c and (E)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-4-triphenylphos-phoranylidene-2-butenoates 4a-c. (Z)-Methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c can be synthesized stereoselectively with high yields when an aqueous DMF solution of 3c, 4c or a mixture of 3a-b and 4a-b was heated at 140℃ for 8 h.展开更多
The risk of hepatocellular carcinoma(HCC) development increases as hepatitis virus C(HCV)-related liver diseases progress,especially in patients with active inflammation.Insight into hepatic carcinogenesis have emerge...The risk of hepatocellular carcinoma(HCC) development increases as hepatitis virus C(HCV)-related liver diseases progress,especially in patients with active inflammation.Insight into hepatic carcinogenesis have emerged from recent detailed analyses of transforming growth factor-β and c-Jun-N-terminal kinase signaling processes directed by multiple phosphorylated(phospho)-isoforms of a Smad3 mediator.In the course of HCV-related chronic liver diseases,chronic inflammation and host genetic/epigenetic alterations additively shift the hepatocytic Smad3 phospho-isoform signaling from tumor suppression to carcinogenesis,increasing the risk of HCC.Chronic inflammation represents an early carcinogenic step that provides a nonmutagenic tumor-promoting stimulus.After undergoing successful antiviral therapy,patients with chronic hepatitis C could experience a lower risk of HCC as Smad3 phospho-isoform signaling reverses from potential carcinogenesis to tumor suppression.Even after HCV clearance,however,patients with cirrhosis could still develop HCC because of sustained,intense carcinogenic Smad3 phospho-isoform signaling that is possibly caused by genetic or epigenetic alterations.Smad3 phospho-isoforms should assist with evaluating the effectiveness of interventions aimed at reducing human HCC.展开更多
Drug repurposing offers an efficient approach to therapeutic development.In this study,our bioinformatic analysis first predicted an association between obesity and lansoprazole(LPZ),a commonly prescribed drug for gas...Drug repurposing offers an efficient approach to therapeutic development.In this study,our bioinformatic analysis first predicted an association between obesity and lansoprazole(LPZ),a commonly prescribed drug for gastrointestinal ulcers.We went on to show that LPZ treatment increased energy expenditure and alleviated the high-fat diet-induced obesity,insulin resistance,and hepatic stea-tosis in mice.Treatment with LPZ elicited thermogenic gene expression and mitochondrial respiration in primary adipocytes,and induced cold tolerance in cold-exposed mice,suggesting the activity of LPZ in promoting adipose thermogenesis and energy metabolism.Mechanistically,LPZ is an efficient inhibitor of adipose phosphocholine phosphatase 1(PHOSPHOI)and produces metabolic benefits in a PHOS-PHO1-dependent manner.Our results suggested that LPZ may stimulate adipose thermogenesis by inhi-biting the conversion of 2-arachidonoylglycerol-lysophosphatidic acid(2-AG-LPA)to 2-arachidonoylglycerol(2-AG)and reduce the activity of the thermogenic-suppressive cannabinoid recep-tor signaling.In summary,we have uncovered a novel therapeutic indication and mechanism of LPZ in managing obesity and its related metabolic syndrome,and identified a potential metabolic basis by which LPZ improves energy metabolism.展开更多
An efficient phospho-aldol reaction of aldehydes catalyzed by N-heterocyclic carbenes （NHCs） has been developed. With 10 mol% stable NHC 1,3-bis（2,6-diisopropylphenyl）imidazol-2-ylidene, various aldehydes reacted ...An efficient phospho-aldol reaction of aldehydes catalyzed by N-heterocyclic carbenes （NHCs） has been developed. With 10 mol% stable NHC 1,3-bis（2,6-diisopropylphenyl）imidazol-2-ylidene, various aldehydes reacted with dialkylphosphites smoothly to provide a-hydroxy phosphonates in 59%--99% yield. In this process, NHC was assumed to function as a carbon-centered bronsted base.展开更多
Dawdle （DDL） is a microRNA processing protein essential for the development of Arabidopsis. DDL contains a putative nuclear localization signal at its amino-terminus and forkhead-associated （FHA） domain at the car...Dawdle （DDL） is a microRNA processing protein essential for the development of Arabidopsis. DDL contains a putative nuclear localization signal at its amino-terminus and forkhead-associated （FHA） domain at the carboxyl-termi- nus. Here, we report the crystal structure of the FHA domain of Arabidopsis Dawdle, determined by multiple-wavelength anomalous dispersion method at 1.7-A resolution. DDL FHA structure displays a seven-stranded 13-sandwich architec- ture that contains a unique structural motif comprising two long anti-parallel strands. Strikingly, crystal packing of the DDL FHA domain reveals that a glutamate residue from the symmetry-related DDL FHA domain, a structural mimic of the phospho-threonine, is specifically recognized by the structurally conserved phospho-threonine binding cleft. Consistently with the structural observations, co-immuno-precipitation experiments performed in Nicotiana benthami- ana show that the DDL FHA domain co-immuno-precipitates with DCL1 fragments containing the predicted pThr＋3（lle/ Val/Leu/Asp） motif. Taken together, we count the recognition of the target residue by the canonical binding cleft of the DDL FHA domain as the key molecular event to instate FHA domain-mediated protein-protein interaction in plant miRNA processing.展开更多
Abnormal expression and dysfunction of methyl-CpG binding protein 2 （MeCP2） cause Rett syndrome （RTT）. The diverse phosphorylation modifications modulate MeCP2 function in neural cells. Using western blot and immu...Abnormal expression and dysfunction of methyl-CpG binding protein 2 （MeCP2） cause Rett syndrome （RTT）. The diverse phosphorylation modifications modulate MeCP2 function in neural cells. Using western blot and immunohistochemistry, we examined the expression patterns of MeCP2 and three phospho-MeCP2s （pMeCP2s） in the developing rat brain. The expression of MeCP2 and phospho-S80 （pS80） MeCP2 increased while pS421 MeCP2 and pS292 MeCP2 decreased with brain maturation. In contrast to the nuclear localization of MeCP2 and pS80 MeCP2, pS421 MeCP2 and pS292 MeCP2 were mainly expressed in the cytoplasmic com- partment. Apart from their distribution in neurons, they were also detected at a low level in astrocytes. Postnatallyinitiated MeCP2 deficiency affected cerebellar neural cell development, as determined by the abnormal expression of GFAP, DCX, Tuj 1, MAP-2, and calbindin-D28k. Together, these results demonstrate that MeCP2 and diverse pMeCP2s have distinct features of spatio-temporal expression in the rat brain, and that the precise levels of MeCP2 in the postnatal period are vital to cerebellar neural cell development.展开更多
Background：The phosphorylation ofp70S6 kinase （p70S6K） represents an important target for sensitive detection on pharmacodynamic effects of sirolimus,but the methods of assessing p70S6K phosphorylation are still un...Background：The phosphorylation ofp70S6 kinase （p70S6K） represents an important target for sensitive detection on pharmacodynamic effects of sirolimus,but the methods of assessing p70S6K phosphorylation are still unclear.The aim of this study was to investigate p70S6K phosphorylation located down-stream of the mammalian target ofrapamycin （mTOR） pathway in peripheral blood mononuclear cells （PBMCs） of liver transplant patients through different methods.Methods：Seventy-five liver transplant recipients from Beijing Chaoyang Hospital of the Capital Medical University were analyzed in this study.Patients were divided into three groups,patient treated with sirolimus （n =22）,patient treated with tacrolimus （n =30）,patient treated with cyclosporine （n =23）.The p70S6K phosphorylation of PBMCs in patients and healthy control （HC,n =12） were analyzed by phospho-flow cytometry and Western blotting.A correlation analysis of data from phospho-flow cytometry and Western blotting was performed.Intra-assay variability of p70S6K phosphorylation in HC and different patients were measured.Results：Intra-assay variability ofp70S6K phosphorylation in phospho-flow cytometry was from 4.1% to 8.4% and in Western blotting was from 8.2% to 18%.The p70S6K phosphorylation in patients receiving a sirolimus （19.5 ± 7.7） was significantly lower than in HC （50.1 ± 11.3,P 〈 0.001）,tacrolimus （37.7 ± 15.7,P 〈 0.001） or cyclosporine treated patients （41.7 ± 11.7,P 〈 0.001）.The p70S6K phosphorylation in HC （50.1± 11.3） was significantly higher than in tacrolimus （37.7 ± 15.7,P 〈 0.01） or cyclosporine-treated patients （41.7 ± 11.7,P 〈 0.01）.There was correlation between data from phospho-flow cytometry and data from Westem blotting （r =0.88,P 〈 0.001）.Conclusions：The degree of mTOR inhibition by assessing p70S6K phosphorylation was established by phospho-flow cytometry and Westem blotting.Assessment of p70S6K phosphorylation may play an adjunct role to on pharmacodynamically guide and individualize sirolimus based on immunosuppression.展开更多
文摘Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
文摘Protein phosphorylation plays an important role in physiological processes, such as muscle contraction. Phospho-specific antibodies have become powerful tools to study these processes. Cardiac myosin binding protein-C (cMyBP-C) is one of the proteins that make up the contractile apparatus of cardiomyocytes. Phosphorylation of cMyBP-C is essential for normal cardiac function, since dephosphorylation of this protein leads to its degradation and has been associated with cardiomyopathy. One of the upstream kinases, which phosphorylate cMyBP-C, is protein kinase D (PKD). While studying the role of PKD in cMyBP-C phosphorylation, we tried to analyze phosphorylation of PKD with a phospho-specific PKD-Ser744/748 antibody. Contrary to the expected 115 kDa, a signal was found for a 150-kDa protein. By MALDI-TOF mass spectrometry, we identified this protein to be cMyBP-C. These data were confirmed by immunostaining using the p-PKD-Ser744/748 antibody, which displayed a striated pattern similar to the one observed for a regular cMyBP-C antibody. To our knowledge there are no antibodies commercially available for phosphorylated cMyBP-C. Thus, the p-PKD-Ser744/748 antibody can accelerate research into the role of cMyBP-C phosphorylation in cardiomyocytes.
基金This prqiect was supported by the National Natural Science Foundation of China, National Science Technology Committee of Chi
文摘Nucleosides were phosphorylated with different N- (O, O-diisopropyl) phosphoryl amino acids to give nucleoside mono phosphates in aqueous solution. 2', 3', and 5'-isomers had been confirmed by comparison with authentic samples on the basis of HPLC analysis. The conversion percentage of nucleoside indicated that N- (O, O-diisopropyl) phosphoryl aspartic acid reacted with adenosine and guanosine at a much higher rate than other kinds of N- phosphoryl amino acids. while phosphorylation of cytidine and uridine was relatively easy by using N- (O, O-diisopropyl) phosphoryl threonine. The result could give some clue to the prebiotic code origin of nucleic acid and protein.
文摘It has been widely recognized that loess has a low stability and permeability,and it is susceptible to a sudden decrease in total volume or collapse upon wetting.When the railway subgrade was under the dynamic trainload,the loess subgrade was prone to instability and liquefaction.loess is higher than that of the cement modified loess,but lower than that of the MPG modified loess.However,the coefficient of permeability for the MPGcement modified loess has an opposite result,and the MPG-cement modified loess specimens have the best frost resistance.In addition,the mechanism of MPG-Bao Zhong railway is a key railway for Guyuan city,in Ningxia province of China,which is an important city of the Belt and Road.Due to the influence of largearea flood irrigation on the farmland,the subgrade had a degree of settlement.The settlement had not been alleviated after three treatments,which seriously affected the safety of the train.For this reason,cement,Modified Phospho Gypsum(MPG)and MPGcement were used to reinforce the subgrade loess,and the unconfined compressive strength test,permeability test and freeze-thaw cycle test were carried out.Then the compressive strength,impermeability and frost resistance of the three were analyzed and compared.The results indicate that the compressive strength of the MPG-cement modified cement modified loess is discussed.It is found that cement and MPG have two hydration reactions with water in loess.Ettringite,the hydration reaction product,which not only fills the pores,restricts the movement of the soil particles,but also acts as a connecting soil particle in the soil particles.Therefore,the strength of the modified loess continues to increase,and the physical properties of the modified loess are improved.
基金supported in part by the National Natural ScienceFoundation of China(No.81702849).
文摘Objective:Diffuse large B-cell lymphoma(DLBCL)is an aggressive type of non-Hodgkin lymphoma.Due to its genetic heterogeneity and abnormal metabolism,many DLBCL patients have a poor prognosis.This study investigated the key metabolism-related genes and potential mechanisms.Methods:Differentially expressed genes,differentially expressed transcription factors(TFs),and differentially expressed metabolism-related genes(DEMRGs)of glucose and lipid metabolic processes were identified using the edgeR package.Key DEMRGs were screened by Lasso regression,and a prediction model was constructed.The cell type identification by estimating relative subsets of RNA transcripts algorithm was utilized to assess the fraction of immune cells,and Gene Set Enrichment Analysis was used to determine immune-related pathways.A regulatory network was constructed with significant co-expression interactions among TFs,DEMRGs,immune cells/pathways,and hallmark pathways.Results:A total of 1551 DEMRGs were identified.A prognostic model with a high applicability(area under the curve=0.921)was constructed with 13 DEMRGs.Tumorigenesis of DLBCL was highly related to the neutrophil count.Four DEMRGs(PRXL2AB,CCN1,DECR2 and PHOSPHO1)with 32 TF-DEMRG,36 DEMRG-pathway,14 DEMRG-immune-cell,9 DEMRG-immune-gene-set,and 67 DEMRG-protein-chip interactions were used to construct the regulatory network.Conclusion:We provided a prognostic prediction model based on 13 DEMRGs for DLBCL.We found that phosphatase,orphan 1(PHOSPHO1)is positively regulated by regulatory factor X5(RFX5)and mediates MYC proto-oncogene(MYC)targeting the V2 pathway and neutrophils.
基金Supported by the National Natural Science Foundation of ChinaFor part XVII of the series, see Chinese J. of Chem. (to be published)
文摘The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl 2-perfluoroalkynoates 2a-c in the presence of K2CO3 at room temperature gives two adducts, (E)-methyl 3-per-fluoroalkyl-4-( 3-carboethoxy-2-furanyl )-2-triphenylphosphoranylidene-3-butenoates 3a-c and (E)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-4-triphenylphos-phoranylidene-2-butenoates 4a-c. (Z)-Methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c can be synthesized stereoselectively with high yields when an aqueous DMF solution of 3c, 4c or a mixture of 3a-b and 4a-b was heated at 140℃ for 8 h.
文摘The risk of hepatocellular carcinoma(HCC) development increases as hepatitis virus C(HCV)-related liver diseases progress,especially in patients with active inflammation.Insight into hepatic carcinogenesis have emerged from recent detailed analyses of transforming growth factor-β and c-Jun-N-terminal kinase signaling processes directed by multiple phosphorylated(phospho)-isoforms of a Smad3 mediator.In the course of HCV-related chronic liver diseases,chronic inflammation and host genetic/epigenetic alterations additively shift the hepatocytic Smad3 phospho-isoform signaling from tumor suppression to carcinogenesis,increasing the risk of HCC.Chronic inflammation represents an early carcinogenic step that provides a nonmutagenic tumor-promoting stimulus.After undergoing successful antiviral therapy,patients with chronic hepatitis C could experience a lower risk of HCC as Smad3 phospho-isoform signaling reverses from potential carcinogenesis to tumor suppression.Even after HCV clearance,however,patients with cirrhosis could still develop HCC because of sustained,intense carcinogenic Smad3 phospho-isoform signaling that is possibly caused by genetic or epigenetic alterations.Smad3 phospho-isoforms should assist with evaluating the effectiveness of interventions aimed at reducing human HCC.
基金This work was supported by the Beijing Municipal Natural Science Foundation Grant 7212148(to Mengxi Jiang,China)the National Natural Science Foundation of China Grant 82000807(to Mengxi Jiang,China)the Beijing Municipal Education Commission Grant KM202110025023(to Mengxi Jiang,China).
文摘Drug repurposing offers an efficient approach to therapeutic development.In this study,our bioinformatic analysis first predicted an association between obesity and lansoprazole(LPZ),a commonly prescribed drug for gastrointestinal ulcers.We went on to show that LPZ treatment increased energy expenditure and alleviated the high-fat diet-induced obesity,insulin resistance,and hepatic stea-tosis in mice.Treatment with LPZ elicited thermogenic gene expression and mitochondrial respiration in primary adipocytes,and induced cold tolerance in cold-exposed mice,suggesting the activity of LPZ in promoting adipose thermogenesis and energy metabolism.Mechanistically,LPZ is an efficient inhibitor of adipose phosphocholine phosphatase 1(PHOSPHOI)and produces metabolic benefits in a PHOS-PHO1-dependent manner.Our results suggested that LPZ may stimulate adipose thermogenesis by inhi-biting the conversion of 2-arachidonoylglycerol-lysophosphatidic acid(2-AG-LPA)to 2-arachidonoylglycerol(2-AG)and reduce the activity of the thermogenic-suppressive cannabinoid recep-tor signaling.In summary,we have uncovered a novel therapeutic indication and mechanism of LPZ in managing obesity and its related metabolic syndrome,and identified a potential metabolic basis by which LPZ improves energy metabolism.
基金the National Natural Science Foundation of China，the Team Innovation Project of Shihezi University
文摘An efficient phospho-aldol reaction of aldehydes catalyzed by N-heterocyclic carbenes （NHCs） has been developed. With 10 mol% stable NHC 1,3-bis（2,6-diisopropylphenyl）imidazol-2-ylidene, various aldehydes reacted with dialkylphosphites smoothly to provide a-hydroxy phosphonates in 59%--99% yield. In this process, NHC was assumed to function as a carbon-centered bronsted base.
文摘Dawdle （DDL） is a microRNA processing protein essential for the development of Arabidopsis. DDL contains a putative nuclear localization signal at its amino-terminus and forkhead-associated （FHA） domain at the carboxyl-termi- nus. Here, we report the crystal structure of the FHA domain of Arabidopsis Dawdle, determined by multiple-wavelength anomalous dispersion method at 1.7-A resolution. DDL FHA structure displays a seven-stranded 13-sandwich architec- ture that contains a unique structural motif comprising two long anti-parallel strands. Strikingly, crystal packing of the DDL FHA domain reveals that a glutamate residue from the symmetry-related DDL FHA domain, a structural mimic of the phospho-threonine, is specifically recognized by the structurally conserved phospho-threonine binding cleft. Consistently with the structural observations, co-immuno-precipitation experiments performed in Nicotiana benthami- ana show that the DDL FHA domain co-immuno-precipitates with DCL1 fragments containing the predicted pThr＋3（lle/ Val/Leu/Asp） motif. Taken together, we count the recognition of the target residue by the canonical binding cleft of the DDL FHA domain as the key molecular event to instate FHA domain-mediated protein-protein interaction in plant miRNA processing.
基金supported by a grant from the National Natural Science Foundation of China(81030020)
文摘Abnormal expression and dysfunction of methyl-CpG binding protein 2 （MeCP2） cause Rett syndrome （RTT）. The diverse phosphorylation modifications modulate MeCP2 function in neural cells. Using western blot and immunohistochemistry, we examined the expression patterns of MeCP2 and three phospho-MeCP2s （pMeCP2s） in the developing rat brain. The expression of MeCP2 and phospho-S80 （pS80） MeCP2 increased while pS421 MeCP2 and pS292 MeCP2 decreased with brain maturation. In contrast to the nuclear localization of MeCP2 and pS80 MeCP2, pS421 MeCP2 and pS292 MeCP2 were mainly expressed in the cytoplasmic com- partment. Apart from their distribution in neurons, they were also detected at a low level in astrocytes. Postnatallyinitiated MeCP2 deficiency affected cerebellar neural cell development, as determined by the abnormal expression of GFAP, DCX, Tuj 1, MAP-2, and calbindin-D28k. Together, these results demonstrate that MeCP2 and diverse pMeCP2s have distinct features of spatio-temporal expression in the rat brain, and that the precise levels of MeCP2 in the postnatal period are vital to cerebellar neural cell development.
文摘Background：The phosphorylation ofp70S6 kinase （p70S6K） represents an important target for sensitive detection on pharmacodynamic effects of sirolimus,but the methods of assessing p70S6K phosphorylation are still unclear.The aim of this study was to investigate p70S6K phosphorylation located down-stream of the mammalian target ofrapamycin （mTOR） pathway in peripheral blood mononuclear cells （PBMCs） of liver transplant patients through different methods.Methods：Seventy-five liver transplant recipients from Beijing Chaoyang Hospital of the Capital Medical University were analyzed in this study.Patients were divided into three groups,patient treated with sirolimus （n =22）,patient treated with tacrolimus （n =30）,patient treated with cyclosporine （n =23）.The p70S6K phosphorylation of PBMCs in patients and healthy control （HC,n =12） were analyzed by phospho-flow cytometry and Western blotting.A correlation analysis of data from phospho-flow cytometry and Western blotting was performed.Intra-assay variability of p70S6K phosphorylation in HC and different patients were measured.Results：Intra-assay variability ofp70S6K phosphorylation in phospho-flow cytometry was from 4.1% to 8.4% and in Western blotting was from 8.2% to 18%.The p70S6K phosphorylation in patients receiving a sirolimus （19.5 ± 7.7） was significantly lower than in HC （50.1 ± 11.3,P 〈 0.001）,tacrolimus （37.7 ± 15.7,P 〈 0.001） or cyclosporine treated patients （41.7 ± 11.7,P 〈 0.001）.The p70S6K phosphorylation in HC （50.1± 11.3） was significantly higher than in tacrolimus （37.7 ± 15.7,P 〈 0.01） or cyclosporine-treated patients （41.7 ± 11.7,P 〈 0.01）.There was correlation between data from phospho-flow cytometry and data from Westem blotting （r =0.88,P 〈 0.001）.Conclusions：The degree of mTOR inhibition by assessing p70S6K phosphorylation was established by phospho-flow cytometry and Westem blotting.Assessment of p70S6K phosphorylation may play an adjunct role to on pharmacodynamically guide and individualize sirolimus based on immunosuppression.
