We cloned the complete coding sequences of porcine Gpr3, Gpr6, and Gpr12 genes. Further, on the basis of their high levels of sequence similarity, these genes are identified as a subfamily of G protein-coupled recepto...We cloned the complete coding sequences of porcine Gpr3, Gpr6, and Gpr12 genes. Further, on the basis of their high levels of sequence similarity, these genes are identified as a subfamily of G protein-coupled receptors. These putative protein sequences also showed high sequence identity with other mammalian orthologs, including several highly conserved motifs. A wide expression of the Gpr3 gene in pigs was observed through tissue distribution analysis by reverse transcriptase-polymerase chain reaction （RT-PCR） and real-time PCR, specially in the brain, pituitary, fat, liver and oocyte, where its strong expression was observed. The Gpr3 gene was found to be located on chromosome 6 and a single exon coded for the entire open reading frame. Expression of porcine Gpr3 in HEK293 cells resulted in constitutive activation of adenylate cyclase （AC） similar in amplitude to that produced by fully stimulated Gs coupled receptors. Moreover, sphingosine 1-phosphate （S1P） could increase AC activation via the constitutively active Gpr3 receptor. When a Gpr3-green fluorescent protein （GFP） construct was expressed in HEK293 cells, GFP-labeled Gpr3 protein was shown to be localized in the plasmalemma and subcellular membranes. After S1P treatment, agonist-mediated internalization could be visualized by confocal microscopy. In short, our findings suggest the porcine Gpr3, Gpr6, and Gpr12 genes as a subfamily of G protein-coupled receptors, and porcine Gpr3 was a constitutively active G protein-coupled receptor. Constitutive activation of AG and agonist-mediated internalization of Gpr3 receptor could be modulated by the S1 P, suggesting that S1P might act as an activator for porcine Gpr3 receptor.展开更多
Hypoxia and aberrant activation of epidermal growth factor receptor(EGFR)are considered important features of various malignancies.However,whether hypoxia can directly trigger EGFR activation and its clinical implicat...Hypoxia and aberrant activation of epidermal growth factor receptor(EGFR)are considered important features of various malignancies.However,whether hypoxia can directly trigger EGFR activation and its clinical implications remain unclear.In this study,we demonstrated that in oral cancer,a typical hypoxic tumor,hypoxia can induce chronic but constitutive phosphorylation of wild-type EGFR in the absence of ligands.Oral cancer cell lines exhibit different EGFR phosphorylation responses to hypoxia.In hypoxic HN4 and HN6 cells,ubiquitination-mediated endocytosis,lysosomal sorting,and degradation lead to low levels of EGFR phosphorylation.However,in CAL-27 and HN30 cells,a novel HIF-1α-induced long noncoding RNA(lnc RNA),EUDAL,can compete with the E3 ligase/adaptor complex c-Cbl/Grb2 for binding to EGFR,stabilizing phosphorylated EGFR(p EGFR)and resulting in sustained activation of EGFR and its downstream STAT3/BNIP3 signaling.STAT3/BNIP3-mediated autophagy leads to antitumor drug resistance.A high EUDAL/EGFR/STAT3/autophagy pathway activation predicts poor response to chemotherapy in oral cancer patients.Collectively,hypoxia can induce noncanonical ligand-independent EGFR phosphorylation.High EUDAL expression facilitates sustained EGFR phosphorylation in hypoxic tumor cells and leads to autophagy-related drug resistance.展开更多
Hot deformation behavior of a novel Ni-Cr-Mo-B heavy plate steel was studied by hot compression tests,which were conducted on a Gleeble-3800thermo-mechanical simulator corresponding to the temperature range of850-1 15...Hot deformation behavior of a novel Ni-Cr-Mo-B heavy plate steel was studied by hot compression tests,which were conducted on a Gleeble-3800thermo-mechanical simulator corresponding to the temperature range of850-1 150℃ with the strain rates of 0.01-10s-1 and the true strain of 0.8.The results suggest that the majority of flow curves exhibit a typical dynamic recrystallization（DRX）behavior with an apparent single peak stress followed by agradual fall towards a steady-state stress.Important characteristic parameters of flow behavior as critical stress/strain for initiation of DRX and peak and steady-state stress/strain were derived from curves of strain hardening rate versus stress and stress versus strain,respectively.Material constants of the investigated steel were determined based on Arrhenius-type constitutive equation,and then the peak stress was predicted by the equation with the hot deformation activation energy of 379 139J/mol,and the predicted values agree well with the experimental values.Furthermore,the effect of Zener-Hollomon parameter on the characteristic points of flow curves was studied using the power law relation,and the ratio of critical stress and strain to peak stress and strain were found to be 0.91and0.46,respectively.展开更多
The 'earthquake nucleation' is discussed in this paper. The acceleration is a property of the nucleation phase and is a necessary condition of earthquake instability too. If the acceleration property of this n...The 'earthquake nucleation' is discussed in this paper. The acceleration is a property of the nucleation phase and is a necessary condition of earthquake instability too. If the acceleration property of this nucleating process is described by the equation dΩ/dt=C/(tf-t)n, the process can be summarized briefly that the rate of cumulative seismic release is proportional to the inverse power of the remaining time to failure. Based on this principle, the foreshock sequence of the 1975 Haicheng earthquake with Ms7.3, was analysed backward. It is stated clearly that the time-to-failure and magnitude of the mainshock can be predicted successfully if the coefficient r2 attains to the maximum. In the estimation of mainshock time, the error can generally be less than, or far less than,one-half the remaining time between the time of the last used data point and the mainshock.展开更多
Epigenetic modulators of the histone deacetylase(HDAC)family control key biological processes and are frequently dysregulated in cancer.There is superior activity of HDAC inhibitors(HDACi)in patients with myeloprolife...Epigenetic modulators of the histone deacetylase(HDAC)family control key biological processes and are frequently dysregulated in cancer.There is superior activity of HDAC inhibitors(HDACi)in patients with myeloproliferative neoplasms(MPNs)that carry the Janus kinase-2 point mutant JAK2^(V617F).This constitutively active tyrosine kinase activates signal-transducer-and-activator-of-transcription(STAT)transcription factors to promote cell proliferation and inflammatory processes.We reveal that the inhibition of HDAC1/HDAC2 with the clinically advanced HDACi romidepsin,the experimental HDACi entinostat and MERCK60,and genetic depletion of HDAC1/HDAC2 induce apoptosis and long-term growth arrest of primary and permanent MPN cells in vitro and in vivo.This treatment spares normal hematopoietic stem cells and does not compromise blood cell differentiation.At the molecular level,HDAC1 and HDAC2 control the protein stability of SIAH2 through acetylation.Genetic knockout experiments show that SIAH2 accelerates the proteasomal degradation of JAK2^(V617F)in conjunction with the E2 ubiquitin-conjugating enzyme UBCH8.SIAH2 binds to the surface-exposed SIAH degron motif VLP1002 in the catalytic domain of JAK2^(V617F).At the functional level,SIAH2 knockout MPN cells are significantly less sensitive to HDACi.Global RNA sequencing verifies that JAK-STAT signaling is a prime target of SIAH2.Moreover,HDAC1 is an adverse prognostic factor in patients with acute myeloid leukemia(n=150,p=0.02),being a possible complication of MPNs.These insights reveal a previously unappreciated link between HDAC1/HDAC2 as key molecular targets,the still undefined regulation of cytoplasmic-to-nuclear signaling by HDACs,and how HDACi kill JAK2^(V617F)-positive cells from MPN patients and mice with JAK2^(V617F)in vitro and in vivo.展开更多
基金Project supported by the National High-Tech R&D Program(863)of China(No.2006AA10Z136)a Grant-in-Aid for Innovative Training of Doctoral Students in Jiangsu Province of China(No.CXLX11-0701)
文摘We cloned the complete coding sequences of porcine Gpr3, Gpr6, and Gpr12 genes. Further, on the basis of their high levels of sequence similarity, these genes are identified as a subfamily of G protein-coupled receptors. These putative protein sequences also showed high sequence identity with other mammalian orthologs, including several highly conserved motifs. A wide expression of the Gpr3 gene in pigs was observed through tissue distribution analysis by reverse transcriptase-polymerase chain reaction （RT-PCR） and real-time PCR, specially in the brain, pituitary, fat, liver and oocyte, where its strong expression was observed. The Gpr3 gene was found to be located on chromosome 6 and a single exon coded for the entire open reading frame. Expression of porcine Gpr3 in HEK293 cells resulted in constitutive activation of adenylate cyclase （AC） similar in amplitude to that produced by fully stimulated Gs coupled receptors. Moreover, sphingosine 1-phosphate （S1P） could increase AC activation via the constitutively active Gpr3 receptor. When a Gpr3-green fluorescent protein （GFP） construct was expressed in HEK293 cells, GFP-labeled Gpr3 protein was shown to be localized in the plasmalemma and subcellular membranes. After S1P treatment, agonist-mediated internalization could be visualized by confocal microscopy. In short, our findings suggest the porcine Gpr3, Gpr6, and Gpr12 genes as a subfamily of G protein-coupled receptors, and porcine Gpr3 was a constitutively active G protein-coupled receptor. Constitutive activation of AG and agonist-mediated internalization of Gpr3 receptor could be modulated by the S1 P, suggesting that S1P might act as an activator for porcine Gpr3 receptor.
基金supported by the National Natural Science Foundation of China(82273095,82203614)the Shanghai Sailing Program(22YF1421600)。
文摘Hypoxia and aberrant activation of epidermal growth factor receptor(EGFR)are considered important features of various malignancies.However,whether hypoxia can directly trigger EGFR activation and its clinical implications remain unclear.In this study,we demonstrated that in oral cancer,a typical hypoxic tumor,hypoxia can induce chronic but constitutive phosphorylation of wild-type EGFR in the absence of ligands.Oral cancer cell lines exhibit different EGFR phosphorylation responses to hypoxia.In hypoxic HN4 and HN6 cells,ubiquitination-mediated endocytosis,lysosomal sorting,and degradation lead to low levels of EGFR phosphorylation.However,in CAL-27 and HN30 cells,a novel HIF-1α-induced long noncoding RNA(lnc RNA),EUDAL,can compete with the E3 ligase/adaptor complex c-Cbl/Grb2 for binding to EGFR,stabilizing phosphorylated EGFR(p EGFR)and resulting in sustained activation of EGFR and its downstream STAT3/BNIP3 signaling.STAT3/BNIP3-mediated autophagy leads to antitumor drug resistance.A high EUDAL/EGFR/STAT3/autophagy pathway activation predicts poor response to chemotherapy in oral cancer patients.Collectively,hypoxia can induce noncanonical ligand-independent EGFR phosphorylation.High EUDAL expression facilitates sustained EGFR phosphorylation in hypoxic tumor cells and leads to autophagy-related drug resistance.
基金Sponsored by National Natural Science Foundation of China(51071019,51371030)National High Technology Research and Development Program of China(2013AA031601)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2011BAE25B01)
文摘Hot deformation behavior of a novel Ni-Cr-Mo-B heavy plate steel was studied by hot compression tests,which were conducted on a Gleeble-3800thermo-mechanical simulator corresponding to the temperature range of850-1 150℃ with the strain rates of 0.01-10s-1 and the true strain of 0.8.The results suggest that the majority of flow curves exhibit a typical dynamic recrystallization（DRX）behavior with an apparent single peak stress followed by agradual fall towards a steady-state stress.Important characteristic parameters of flow behavior as critical stress/strain for initiation of DRX and peak and steady-state stress/strain were derived from curves of strain hardening rate versus stress and stress versus strain,respectively.Material constants of the investigated steel were determined based on Arrhenius-type constitutive equation,and then the peak stress was predicted by the equation with the hot deformation activation energy of 379 139J/mol,and the predicted values agree well with the experimental values.Furthermore,the effect of Zener-Hollomon parameter on the characteristic points of flow curves was studied using the power law relation,and the ratio of critical stress and strain to peak stress and strain were found to be 0.91and0.46,respectively.
文摘The 'earthquake nucleation' is discussed in this paper. The acceleration is a property of the nucleation phase and is a necessary condition of earthquake instability too. If the acceleration property of this nucleating process is described by the equation dΩ/dt=C/(tf-t)n, the process can be summarized briefly that the rate of cumulative seismic release is proportional to the inverse power of the remaining time to failure. Based on this principle, the foreshock sequence of the 1975 Haicheng earthquake with Ms7.3, was analysed backward. It is stated clearly that the time-to-failure and magnitude of the mainshock can be predicted successfully if the coefficient r2 attains to the maximum. In the estimation of mainshock time, the error can generally be less than, or far less than,one-half the remaining time between the time of the last used data point and the mainshock.
基金funded by the German Academic Exchange Service/Deutscher Akademischer Austauschdienst(DAAD)the German Research Foundation/Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)KR2291/12-1/12-2,project number 445785155.O.H.K+13 种基金funding from the DFG–project number 393547839–SFB 1361,sub-project 11KR2291/14-1,project number 469954457KR2291/15-1,project number 495271833KR2291/16-1,project number 496927074KR2291/16-1,project number 496927074KR2291/17-1,project number 502534123KR2291/18-1,project number 528202295funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)–Project-ID 393547839–SFB 1361the Brigitte und Dr.Konstanze Wegener-Stiftungthe Walter Schulz-Stiftungthe José Carreras Leukemia FoundationSupport by the IMB Genomics Core Facility and the use of its NextSeq500 funded by the(DFG–329045328)funding by DFG Project-ID 318346496-SFB1292 TP21Nsupported by grants from the German Research Council(DFG):HE6233/15-1 and 16-1,project number 517204983 and HE6233/4-2,project number 320028127.
文摘Epigenetic modulators of the histone deacetylase(HDAC)family control key biological processes and are frequently dysregulated in cancer.There is superior activity of HDAC inhibitors(HDACi)in patients with myeloproliferative neoplasms(MPNs)that carry the Janus kinase-2 point mutant JAK2^(V617F).This constitutively active tyrosine kinase activates signal-transducer-and-activator-of-transcription(STAT)transcription factors to promote cell proliferation and inflammatory processes.We reveal that the inhibition of HDAC1/HDAC2 with the clinically advanced HDACi romidepsin,the experimental HDACi entinostat and MERCK60,and genetic depletion of HDAC1/HDAC2 induce apoptosis and long-term growth arrest of primary and permanent MPN cells in vitro and in vivo.This treatment spares normal hematopoietic stem cells and does not compromise blood cell differentiation.At the molecular level,HDAC1 and HDAC2 control the protein stability of SIAH2 through acetylation.Genetic knockout experiments show that SIAH2 accelerates the proteasomal degradation of JAK2^(V617F)in conjunction with the E2 ubiquitin-conjugating enzyme UBCH8.SIAH2 binds to the surface-exposed SIAH degron motif VLP1002 in the catalytic domain of JAK2^(V617F).At the functional level,SIAH2 knockout MPN cells are significantly less sensitive to HDACi.Global RNA sequencing verifies that JAK-STAT signaling is a prime target of SIAH2.Moreover,HDAC1 is an adverse prognostic factor in patients with acute myeloid leukemia(n=150,p=0.02),being a possible complication of MPNs.These insights reveal a previously unappreciated link between HDAC1/HDAC2 as key molecular targets,the still undefined regulation of cytoplasmic-to-nuclear signaling by HDACs,and how HDACi kill JAK2^(V617F)-positive cells from MPN patients and mice with JAK2^(V617F)in vitro and in vivo.
