The characterization and functions of transmembrane protein 59-like(TMEM59L),a type I transmembrane protein,are not clearly understood until now.Some TMEM59L and fluorescent fusion proteins constructs were transfected...The characterization and functions of transmembrane protein 59-like(TMEM59L),a type I transmembrane protein,are not clearly understood until now.Some TMEM59L and fluorescent fusion proteins constructs were transfected in cell lines and liposomes,and their localization was observed.The effects of protein constructs were studied by fluorescence microscopy and western blotting.This study reports a novel function of human TMEM59L(hTMEM59L)related to the expression and location of some proteins.In addition,we report two novel splice variants of human TMEM59L(hTMEM59L).The localization of mutants of this protein,lacking a middle region,and a Cterminal deletion,markedly differed from that of full-length hTMEM59L.Intracellular movement assessment in living cells showed the localization of TMEM59L to vesicular structures in the Golgi bodies,and the cell membrane was observed in living cells.Overexpression of TMEM59L markedly increased the level of amyloid precursor protein because of TMEM59L-mediated inhibition of cell membrane transport but did not affect the expression of betasecretase 2.TMEM59L overexpression also significantly increased the levels of Rab GDP dissociation inhibitor alpha and Rab GDP dissociation inhibitor beta proteins.These results suggest that TMEM59L is involved in the packaging of acidic vesicles and thereby functions in the trafficking and processing of intracellular proteins.展开更多
Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely st...Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely studied model system for Coronavirus replication and pathogenesis. In this study,we created a MHV-A59 temperature sensitive (ts) mutant Wu"-ts18(cd) using the recombinant vaccinia reverse genetics system. Virus replication assay in 17C1-1 cells showed the plaque phenotype and replication characterization of constructed Wu"-ts18(cd) were indistinguishable from the reported ts mutant Wu"-ts18. Then we cultured the ts mutant Wu"-ts18(cd) at non-permissive temperature 39.5°C,which "forced" the ts recombinant virus to use second-site mutation to revert from a ts to a non-ts phenotype. Sequence analysis showed most of the revertants had the same single amino acid mutation at Nsp16 position 43. The single amino acid mutation at Nsp16 position 76 or position 130 could also revert the ts mutant Wu"-ts18 (cd) to non-ts phenotype,an additional independent mutation in Nsp13 position 115 played an important role on plaque size. The results provided us with genetic information on the functional determinants of Nsp16. This allowed us to build up a more reasonable model of CoVs replication-transcription complex.展开更多
OBJECTIVE: To assess complement-mediated myocardial injury on isolated guinea pig working hearts and cardioprotective effects of CD59. METHODS: Using a modified Langendorff apparatus, isolated guinea-pig working heart...OBJECTIVE: To assess complement-mediated myocardial injury on isolated guinea pig working hearts and cardioprotective effects of CD59. METHODS: Using a modified Langendorff apparatus, isolated guinea-pig working hearts were perfused with a modified Krebs Henseleit buffer containing 3% heat-inactivated human plasma and zymosan (IPZ) (control) (n = 10), 3% normal human plasma and zymosan (NPZ) (n = 10), or 3% normal human plasma and zymosan and 1.5 microg/ml CD59 (NPZC) (n = 10), respectively. Epicardial electrocardiogram (ECG), cardiac output (CO), coronary arterial flow (CF), maximum left ventricular developed pressure (LVP(max)), maximum left ventricular developed pressure increase rate (+ dp/dt(max)), maximum left ventricular developed pressure decrease rate (- dp/dt(max)) and heart rate (HR) were recorded at 0, 15, 30, 45 and 60 min of treatment. After the experiment, immunohistochemical examination was performed to detect the presence of C3a or C5b-9 in the myocardium of the isolated hearts. RESULTS: Compared the IPZ group, hearts treated with NPZ showed a slight depression on ST segments of epicardial ECG at 15 min, a significant elevation between 30 min to 60 min, a decrease in CF, CO, LVP(max), + dp/dt(max) and - dp/dt(max), and an increase in HR at 15 min. The observed alterations in CF, CO, LVP(max), + dp/dt(max) and - dp/dt(max) remained decreased, while the HR remained increased until the end of the protocol. The all above parameters of hearts treated with NPZC were similar to the control group (IPZ) at any given time. Immunohistochemical examination showed positive signals of C3a and C5b-9 in the myocardium of hearts treated with NPZ. C3a was positive in NPZC, and C3a and C5b-9 were negative in IPZ. CONCLUSIONS: Activated human complements directly damage isolated guinea pig working hearts, and CD59 offers a significant protection against the injuries.展开更多
A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandii Llpmann. After analysis by matrix-assisted laser desorptlon ionization tim...A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandii Llpmann. After analysis by matrix-assisted laser desorptlon ionization time-of-flight mass spectrometry, the protein was Identified as the product of a predicted gene. Thus, the protein was tentatively called HBP59. Its absorption spectra （ABS） In the reduced state exhibited three peaks at 421,517, and 556 nm and the maximal peak was shifted from 421 to 413 nm after exposure of HBP59 to air. The Soret circular dichrolsm （CD） spectrum of HBP59 In the reduced state displayed four positive peaks at 364, 382, 406, and 418 nm and two negative peaks at 398 and 433 nm; the △ε （CD extinction coefficient） values of these peaks were found to be 0.92, 0.58, 0.87, 0.72, -0.65 and -1.12 L/mol per cm, respectively. Titration with heme showed that the protein has 0.1 heme molecules/protein molecule. After HBP59 had fully Interacted with heme, Its maximal ABS value and Soret CD Intensity were increased by approximately 10-fold compared with values before Interaction. Therefore, It seems that one molecule of HBP59 can be interacted with only one heme. These results indicate that HBP59 contains heme with low spin and may be Involved In heme utilization or adhesion.展开更多
基金This work was supported by the Science and Technology Development Plan of Kaifeng in 2020(2003048)the National Natural Science Foundation of China(Grant No.31070954).
文摘The characterization and functions of transmembrane protein 59-like(TMEM59L),a type I transmembrane protein,are not clearly understood until now.Some TMEM59L and fluorescent fusion proteins constructs were transfected in cell lines and liposomes,and their localization was observed.The effects of protein constructs were studied by fluorescence microscopy and western blotting.This study reports a novel function of human TMEM59L(hTMEM59L)related to the expression and location of some proteins.In addition,we report two novel splice variants of human TMEM59L(hTMEM59L).The localization of mutants of this protein,lacking a middle region,and a Cterminal deletion,markedly differed from that of full-length hTMEM59L.Intracellular movement assessment in living cells showed the localization of TMEM59L to vesicular structures in the Golgi bodies,and the cell membrane was observed in living cells.Overexpression of TMEM59L markedly increased the level of amyloid precursor protein because of TMEM59L-mediated inhibition of cell membrane transport but did not affect the expression of betasecretase 2.TMEM59L overexpression also significantly increased the levels of Rab GDP dissociation inhibitor alpha and Rab GDP dissociation inhibitor beta proteins.These results suggest that TMEM59L is involved in the packaging of acidic vesicles and thereby functions in the trafficking and processing of intracellular proteins.
基金Research Grants from State Key Laboratory of Pathogen and Biosecurity (SKLPBS0918)
文摘Coronaviruses (CoVs) are generally associated with respiratory and enteric infections and have long been recognized as important pathogens of livestock and companion animals. Mouse hepatitis virus (MHV) is a widely studied model system for Coronavirus replication and pathogenesis. In this study,we created a MHV-A59 temperature sensitive (ts) mutant Wu"-ts18(cd) using the recombinant vaccinia reverse genetics system. Virus replication assay in 17C1-1 cells showed the plaque phenotype and replication characterization of constructed Wu"-ts18(cd) were indistinguishable from the reported ts mutant Wu"-ts18. Then we cultured the ts mutant Wu"-ts18(cd) at non-permissive temperature 39.5°C,which "forced" the ts recombinant virus to use second-site mutation to revert from a ts to a non-ts phenotype. Sequence analysis showed most of the revertants had the same single amino acid mutation at Nsp16 position 43. The single amino acid mutation at Nsp16 position 76 or position 130 could also revert the ts mutant Wu"-ts18 (cd) to non-ts phenotype,an additional independent mutation in Nsp13 position 115 played an important role on plaque size. The results provided us with genetic information on the functional determinants of Nsp16. This allowed us to build up a more reasonable model of CoVs replication-transcription complex.
基金theScientificResearchFoundationoftheMinistryofHealth ,China (No .96 1115 )
文摘OBJECTIVE: To assess complement-mediated myocardial injury on isolated guinea pig working hearts and cardioprotective effects of CD59. METHODS: Using a modified Langendorff apparatus, isolated guinea-pig working hearts were perfused with a modified Krebs Henseleit buffer containing 3% heat-inactivated human plasma and zymosan (IPZ) (control) (n = 10), 3% normal human plasma and zymosan (NPZ) (n = 10), or 3% normal human plasma and zymosan and 1.5 microg/ml CD59 (NPZC) (n = 10), respectively. Epicardial electrocardiogram (ECG), cardiac output (CO), coronary arterial flow (CF), maximum left ventricular developed pressure (LVP(max)), maximum left ventricular developed pressure increase rate (+ dp/dt(max)), maximum left ventricular developed pressure decrease rate (- dp/dt(max)) and heart rate (HR) were recorded at 0, 15, 30, 45 and 60 min of treatment. After the experiment, immunohistochemical examination was performed to detect the presence of C3a or C5b-9 in the myocardium of the isolated hearts. RESULTS: Compared the IPZ group, hearts treated with NPZ showed a slight depression on ST segments of epicardial ECG at 15 min, a significant elevation between 30 min to 60 min, a decrease in CF, CO, LVP(max), + dp/dt(max) and - dp/dt(max), and an increase in HR at 15 min. The observed alterations in CF, CO, LVP(max), + dp/dt(max) and - dp/dt(max) remained decreased, while the HR remained increased until the end of the protocol. The all above parameters of hearts treated with NPZC were similar to the control group (IPZ) at any given time. Immunohistochemical examination showed positive signals of C3a and C5b-9 in the myocardium of hearts treated with NPZ. C3a was positive in NPZC, and C3a and C5b-9 were negative in IPZ. CONCLUSIONS: Activated human complements directly damage isolated guinea pig working hearts, and CD59 offers a significant protection against the injuries.
基金Supported by the State Key Basic Research and Development Plan of China （001CB1089-06） and the National Natural Science Foundation of China （30270296）.Acknowledgements The authors thank Professors YX Jing and JG Li for their valuable advice.
文摘A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandii Llpmann. After analysis by matrix-assisted laser desorptlon ionization time-of-flight mass spectrometry, the protein was Identified as the product of a predicted gene. Thus, the protein was tentatively called HBP59. Its absorption spectra （ABS） In the reduced state exhibited three peaks at 421,517, and 556 nm and the maximal peak was shifted from 421 to 413 nm after exposure of HBP59 to air. The Soret circular dichrolsm （CD） spectrum of HBP59 In the reduced state displayed four positive peaks at 364, 382, 406, and 418 nm and two negative peaks at 398 and 433 nm; the △ε （CD extinction coefficient） values of these peaks were found to be 0.92, 0.58, 0.87, 0.72, -0.65 and -1.12 L/mol per cm, respectively. Titration with heme showed that the protein has 0.1 heme molecules/protein molecule. After HBP59 had fully Interacted with heme, Its maximal ABS value and Soret CD Intensity were increased by approximately 10-fold compared with values before Interaction. Therefore, It seems that one molecule of HBP59 can be interacted with only one heme. These results indicate that HBP59 contains heme with low spin and may be Involved In heme utilization or adhesion.
