Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression p...Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression profiles of paternally expressed imprinted genes have not been fully explored. In this study, three mouse pES cell lines were established and the differentiation potential of these cells in extended culture was evaluated. The undifferentiated cells had a normal karyotype and homozygous genome, and expressed ES-cell-specific molecular markers. The cells remained undifferentiated after more than 50 passages and exhibited pluripotent differentiation capacity. All three lines of the established ES cells produced teratomas; two lines of ES cells produced chimeras and germline transmission. Furthermore, activation of the paternally expressed imprinted genes Snrpn, U2afl-rsl, Peg3, Impact, Zfp127, Dlkl and Mest in these cells was detected. Some paternally expressed imprinted genes were found to be expressed in the blastocyst stage of parthenogenetically activated embryos in vitro and their expression level increased with extended pES cell culture. Furthermore, our data show that the activation of these paternally expressed imprinted genes in pES cells was associated with a change in the methylation of the related differentially methylated regions. These findings provide direct evidence for the pluripotency of pES cells and demonstrate the association between the DNA methylation pattern and the activa- tion of paternally expressed imprinted genes in pES cells. Thus, the established ES cell lines provide a valuable model for studying epigenetic regulation in mammalian development.展开更多
BACKGROUND: The effects of gangrenous cholecystitis (GC) and consequent surgical interventions on the clinical outcomes and prognosis of patients with severe acute pancreatitis are not clear. The present study was to ...BACKGROUND: The effects of gangrenous cholecystitis (GC) and consequent surgical interventions on the clinical outcomes and prognosis of patients with severe acute pancreatitis are not clear. The present study was to characterize the clinical outcomes of patients with severe acute pancreatitis complicated with GC. METHODS: We retrospectively analyzed 253 consecutive patients hospitalized for acute pancreatitis in intensive care unit. Among them, 68 were diagnosed as having severe acute pancreatitis; 10 out of the 68 patients had GC. We compared these 10 patients with GC and 58 patients without GC. The indices analyzed included sepsis/septic shock, pancreatic encephalopathy, acute respiratory distress syndrome, acute renal failure, multiple organ dysfunction syndrome, and death. RESULTS: Specific CT images of GC in patients with severe acute pancreatitis included enlarged and high-tensioned gallbladder, wall thickening, lumenal emphysema, discontinuous and/or irregular enhancement of mucosa, and pericholecystic effusion. The rates of severe sepsis/septic shock (70.0% vs 24.1%, P【0.01), pancreatic encephalopathy (50.0% vs 17.2%, P【0.05), acute respiratory distress syndrome (90.0% vs 41.4%, P【0.01), multiple organ dysfunction syndrome (70.0% vs 24.1%, P【0.01), acute renal failure (40.0% vs 27.6%, P【0.05), and death (40.0% vs 13.8%, P【0.05) were significantly higher in patients with GC than in those without GC.CONCLUSION: CT scans can help to identify early GC in patients with severe acute pancreatitis; early diagnosis and intervention for patients with GC can reduce morbidity and mortality.展开更多
γ-Aminobutyric acid and GABAergic receptors were previously reported to be distributed in reproductive systems besides CNS and predicted to participate in the modulation of testicular function. γ-Aminobutyric acid t...γ-Aminobutyric acid and GABAergic receptors were previously reported to be distributed in reproductive systems besides CNS and predicted to participate in the modulation of testicular function. γ-Aminobutyric acid transporter was implicated to be involved in this process. However, the potential role of γ-aminobutyric transporter in testis has not been explored. In this study, we investigated the existence of mouse γ-aminobutyric acid transporter subtype I (mGAT1) in testis. Wild-type and transgenic mice, which overexpressing mGAT1 in a variety of tissues, especially in testis, were primarily studied to approach the profile of mGAT1 in testis. Mice with overexpressed mGAT1 develop normally but with reduced mass and size of testis as compared with wild-type. Testicular morphology of transgenic mice exhibited overt abnormalities including focal damage of the spermatogenic epithelium accompanied by capillaries proliferation and increased diameter of seminiferous tubules lumen. Reduced number of spermatids was also found in some seminiferous tubules. Our results clearly demonstrate the presence of GAT1 in mouse testis and imply that GAT1 is possibly involved in testicular function.展开更多
Glutamate transporter EAACl removes excitatory neurotransmitter in central nervous system, and also absorbs glutamate in epithelia of intestine, kidney, liver and heart for normal cell growth. When a mouse cDNA was sc...Glutamate transporter EAACl removes excitatory neurotransmitter in central nervous system, and also absorbs glutamate in epithelia of intestine, kidney, liver and heart for normal cell growth. When a mouse cDNA was screened using EAACl cDNA fragment as probe in our lab, a transcript (GenBank U75214) encoding an EAACl protein with 148 residues truncated at N-terminal was cloned and named as EAAC2. Sequence analysis shows that EAAC2 has it's own start code and unique 5'UTR that is different from that of EAACl. A mouse genomic library was screened and a positive clone including EAACl CDS was sequenced (GenBank AF 322393) and indicates that normal EAACl transcript (GenBank U73521) is transcribed from 10 exons in terms of exon Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ, Ⅶ, Ⅷ,Ⅸ, Ⅹ, and EAAC2 transcript is consisted by exons from IV to IX as same as that of EAACl and with its unique exon β upstream to exon Ⅳ and exon δ downstream to IX. EAAC2 transcript has a cluster of transcriptional start sites not overlapping with the transcriptional start sites of EAACl. These results indicate that EAAC2 is transcribed from an independent promoter but not an alternative splicing event.展开更多
Transgenic mice ubiquitously overexpressing murine γ aminobutyric acid transporter subtype Ⅰ were created. Unexpectedly, these mice markedly exhibited heritable obesity, which features significantly increased body w...Transgenic mice ubiquitously overexpressing murine γ aminobutyric acid transporter subtype Ⅰ were created. Unexpectedly, these mice markedly exhibited heritable obesity, which features significantly increased body weight and fat deposition. Behavioral examination revealed that transgeinc mice have slightly reduced spontaneous locomotive capacity and altered feeding pattern. Tills preliminary finding indicates that the inappropriate level of γ-aminobutyric acid transporters may be directly or indirectly involved in the pathogenic mechanism underlying certain types of obesity.展开更多
The norepinephrine transporter(NET) is a member of the Na+/Cl- dependent neurotransmitter transporter family and constitutes the target of several clinically important antidepressants. To delineate the critical amino ...The norepinephrine transporter(NET) is a member of the Na+/Cl- dependent neurotransmitter transporter family and constitutes the target of several clinically important antidepressants. To delineate the critical amino acid residues and the function of C-terminal in regulating transport activity of NET, here we constructed two site mutants (V70F, F72V; V70I, F72V) and one C-terminal truncated mutant (△611-617). The wild type and mutants of NET were expressed in Xenopus oocytes by injection of their cRNA. We found that all of these mutants lost their transport activity. These results indicate that the amino acid residues of V70 and F72 3 and the last seven amino acids of C-terminal are essential to the transport activity of NET.展开更多
BACKGROUND The recognized pattern of cervical lymph node metastasis(CLNM)of papillary thyroid carcinoma involves a stepwise route.Contralateral lymph node skip metastasis is very rare.In addition,the patient in our ca...BACKGROUND The recognized pattern of cervical lymph node metastasis(CLNM)of papillary thyroid carcinoma involves a stepwise route.Contralateral lymph node skip metastasis is very rare.In addition,the patient in our case report also suffered from a breast carcinoma accompanied by left supraclavicular lymphadenopathy,which made it difficult to distinguish the origin of the CLNM.Based on this case,we recommended that more detailed physical and imaging examinations are needed for patients with uncommon cervical lymphatic metastasis of primary cancer.CASE SUMMARY A 53-year-old women was admitted to the hospital for a neck mass in the left cervical region that had existed for 2 mo.The neck mass was suspected to be an enlarged lateral LN originating from papillary thyroid microcarcinoma of the contralateral thyroid lobe,according to ultrasound and ultrasound-guided fine needle aspiration biopsy.The patient underwent total thyroidectomy and radical cervical LN dissection.Postoperative pathology confirmed the diagnosis of papillary thyroid microcarcinoma with contralateral lymphatic skip metastasis.Unfortunately,a breast cancer was discovered 4 mo later,which was accompanied by ipsilateral supraclavicular LN metastasis.She accepted neoadjuvant chemotherapy and subsequent left modified radical mastectomy for treatment.The patient is currently receiving postoperative radiotherapy,and no local recurrence was observed in the 6-mo follow-up after surgery.CONCLUSIONWe present a rare case of papillary thyroid microcarcinoma with contralateral lymphatic skipmetastasis and breast cancer with supraclavicular lymphatic metastasis.展开更多
The human norepinephrine transporter(NET) gene was cloned and structurally analyzed. The far 5’ fragment containing exon 1 (a non-coding exon) and exon 2 was sequenced. The transcription start site of the gene in hum...The human norepinephrine transporter(NET) gene was cloned and structurally analyzed. The far 5’ fragment containing exon 1 (a non-coding exon) and exon 2 was sequenced. The transcription start site of the gene in human brain stem tissue was determined by primer extension analysis. It was found that the gene could be transcribed from multiple starting points. The 5’ flanking sequence contains a proximal G-C rich region, one possible GSG elemeflt and several SP1 sites. However it does not contain TATA box and CAAT box motifS. Gel shift analysis with nuclear extracts from different tissues of mouse shows that the G-C rich region may be involved in tissue specific expression of the gene.展开更多
A cDNA molecule encoding a major part of the hu-man Norepinephrine transporter(hNET) was synthesized by means of Polymerase Chain Reaction(PCR) technique and used as a probe for selecting the human genomic NET gene. A...A cDNA molecule encoding a major part of the hu-man Norepinephrine transporter(hNET) was synthesized by means of Polymerase Chain Reaction(PCR) technique and used as a probe for selecting the human genomic NET gene. A positive clone harbouring the whole gene was ob-tained from a human lymphocyte genomic library through utilizing the "genomic walking" technique. The clone, des-ignated as phNET, harbours a DNA fragment of about 59 kb in length inserted into BamH Ⅰ site in cosmid pWE15.The genomic clone contains 14 exons encoding all amino acid residues in the protein. A single exon encodes a dis-tinct transmembrane domaill, except for transmembrane domain 10 and 11, which are encoded by part of two ex-ons respectively, and exon 12, which encodes part of do-main 11 and all of domain 12. These results imply that there is a close relationship between exon splicing of a gene and structural domains of the protein, as is the case for the human γ-aminobutyric acid transporter(hGAT) and a number of other membrane proteins.展开更多
DNA methyltransferase 3A (Dnmt3a), a de novo methyltransferase, has attracted a great deal of attention for its important role played in tumorigenesis. We have previously demonstrated that melanoma is unable to grow i...DNA methyltransferase 3A (Dnmt3a), a de novo methyltransferase, has attracted a great deal of attention for its important role played in tumorigenesis. We have previously demonstrated that melanoma is unable to grow in-vivo in conditions of Dnmt3a depletion in a mouse model. In this study, we cultured the Dnmt3a depletion B16 melanoma (Dnmt3a-D) cell line to conduct a comparative analysis of protein expression con-comitant with Dnmt3a depletion in a melanoma cell line. After two-dimensional separation, by gel electro-phoresis and liquid chromatography, combined with mass spectrometry analysis (1DE-LC-MS/MS), the re-sults demonstrated that 467 proteins were up-regulated and 535 proteins were down-regulated in the Dnmt3a-D cell line compared to the negative control (NC) cell line. The Genome Ontology (GO) and KEGG pathway were used to further analyze the altered proteins. KEGG pathway analysis indicated that the MAPK signaling pathway exhibited a greater alteration in proteins, an interesting finding due to the close relation-ship with tumorigenesis. The results strongly suggested that Dnmt3a potentially controls the process of tu-morigenesis through the regulation of the proteins (JNK1, p38α, ERK1, ERK2, and BRAF) involved in tu-mor-related pathways, such as the MAPK signaling pathway and melanoma pathway.展开更多
Background： The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin （DC-SIGN） in renal tubular epithelial cells has been thought to be highly correlated with the occurrence ...Background： The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin （DC-SIGN） in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases, but whether it takes place in renal tissues during hemorrhagic shock （HS） is unknown. The present study airned to investigate this phenomenon and the inhibitory effect of Vitamin C （VitC）. Methods： A Sprague Dawley rat HS model was established in vivo in this study. The expression level and location of DC-SIGN were observed in kidneys. Also, the degree of histological damage, the concentrations of tumor necrosis factor-or and interleukin-6 in the renal tissues, and the serum concentration of blood urea nitrogen and creatinine at different times （2-24 h） alter HS （six rats in each group）, with or without VitC treatment belbre resuscitation, were evaluated. Results： HS induced DC-SIGN expression in rat tubular epithelial cells. The proinflarnmatory cytokine concentration, histological damage scores, and functional injury of kidneys had increased. All these phenornena induced by HS were relieved when the rats were treated with VitC before resuscitation. Conclusions： The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN, and the levels of proinflarnmatory cytokines in the kidney tissues improved correspondingly. The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney.展开更多
Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated Rdh13 knockout mice and showed that R...Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated Rdh13 knockout mice and showed that Rdh13 deficiency causes severe acute retinal light damage. In this study, considering that Rdh13 is highly expressed in mouse liver, we further evaluated the potential effect of Rdh13 on liver injury induced by carbon tetrachloride (CC14). Although Rdh13 deficiency showed no significant effect on liver histology and physiological functions under regular culture, the Rdh13^-/- mice displayed an attenuated response to CCl4-induced liver injury. Their livers also exhibited less histological changes and contained lower levels of liver-related metabolism enzymes compared with the livers of wild-type (WT) mice. Furthermore, the Rdhl3 1 mice had Rdh13 deficiency and thus their liver cells were protected from apoptosis, and the quantity of their proliferative cells became lower than that in WT after CC14 exposure. The ablation of Rdhl3 gene decreased the expression levels of thyroid hormone-inducible nuclear protein 14 (Spot14) and cytochrome P450 (Cyp2el) in the liver, especially after CC14 treatment for 48 h. These data suggested that the alleviated liver damage induced by CC14 in Rdh13^-/- mice was caused by Cyp2el enzymes, which promoted reductive CC14 metabolism by altering the status of thyroxine metabolism. This result further implicated Rdhl3 as a potential drug target in preventing chemically induced liver injury.展开更多
文摘Parthenogenetic embryonic stem （pES） cells provide a valuable in vitro model system for studying the molecular mechanisms that underlie genomic imprinting. However, the pluripotency of pES cells and the expression profiles of paternally expressed imprinted genes have not been fully explored. In this study, three mouse pES cell lines were established and the differentiation potential of these cells in extended culture was evaluated. The undifferentiated cells had a normal karyotype and homozygous genome, and expressed ES-cell-specific molecular markers. The cells remained undifferentiated after more than 50 passages and exhibited pluripotent differentiation capacity. All three lines of the established ES cells produced teratomas; two lines of ES cells produced chimeras and germline transmission. Furthermore, activation of the paternally expressed imprinted genes Snrpn, U2afl-rsl, Peg3, Impact, Zfp127, Dlkl and Mest in these cells was detected. Some paternally expressed imprinted genes were found to be expressed in the blastocyst stage of parthenogenetically activated embryos in vitro and their expression level increased with extended pES cell culture. Furthermore, our data show that the activation of these paternally expressed imprinted genes in pES cells was associated with a change in the methylation of the related differentially methylated regions. These findings provide direct evidence for the pluripotency of pES cells and demonstrate the association between the DNA methylation pattern and the activa- tion of paternally expressed imprinted genes in pES cells. Thus, the established ES cell lines provide a valuable model for studying epigenetic regulation in mammalian development.
基金supported by a grant from Science and Technology Commission of Shanghai Municipality (12411950500)
文摘BACKGROUND: The effects of gangrenous cholecystitis (GC) and consequent surgical interventions on the clinical outcomes and prognosis of patients with severe acute pancreatitis are not clear. The present study was to characterize the clinical outcomes of patients with severe acute pancreatitis complicated with GC. METHODS: We retrospectively analyzed 253 consecutive patients hospitalized for acute pancreatitis in intensive care unit. Among them, 68 were diagnosed as having severe acute pancreatitis; 10 out of the 68 patients had GC. We compared these 10 patients with GC and 58 patients without GC. The indices analyzed included sepsis/septic shock, pancreatic encephalopathy, acute respiratory distress syndrome, acute renal failure, multiple organ dysfunction syndrome, and death. RESULTS: Specific CT images of GC in patients with severe acute pancreatitis included enlarged and high-tensioned gallbladder, wall thickening, lumenal emphysema, discontinuous and/or irregular enhancement of mucosa, and pericholecystic effusion. The rates of severe sepsis/septic shock (70.0% vs 24.1%, P【0.01), pancreatic encephalopathy (50.0% vs 17.2%, P【0.05), acute respiratory distress syndrome (90.0% vs 41.4%, P【0.01), multiple organ dysfunction syndrome (70.0% vs 24.1%, P【0.01), acute renal failure (40.0% vs 27.6%, P【0.05), and death (40.0% vs 13.8%, P【0.05) were significantly higher in patients with GC than in those without GC.CONCLUSION: CT scans can help to identify early GC in patients with severe acute pancreatitis; early diagnosis and intervention for patients with GC can reduce morbidity and mortality.
基金grants from National Science Foundation!No.39630140
文摘γ-Aminobutyric acid and GABAergic receptors were previously reported to be distributed in reproductive systems besides CNS and predicted to participate in the modulation of testicular function. γ-Aminobutyric acid transporter was implicated to be involved in this process. However, the potential role of γ-aminobutyric transporter in testis has not been explored. In this study, we investigated the existence of mouse γ-aminobutyric acid transporter subtype I (mGAT1) in testis. Wild-type and transgenic mice, which overexpressing mGAT1 in a variety of tissues, especially in testis, were primarily studied to approach the profile of mGAT1 in testis. Mice with overexpressed mGAT1 develop normally but with reduced mass and size of testis as compared with wild-type. Testicular morphology of transgenic mice exhibited overt abnormalities including focal damage of the spermatogenic epithelium accompanied by capillaries proliferation and increased diameter of seminiferous tubules lumen. Reduced number of spermatids was also found in some seminiferous tubules. Our results clearly demonstrate the presence of GAT1 in mouse testis and imply that GAT1 is possibly involved in testicular function.
基金This research was supported by foundations fromChinese Academy of Sciences and Special Funds forMajor State Basic Research of China (G19990539).
文摘Glutamate transporter EAACl removes excitatory neurotransmitter in central nervous system, and also absorbs glutamate in epithelia of intestine, kidney, liver and heart for normal cell growth. When a mouse cDNA was screened using EAACl cDNA fragment as probe in our lab, a transcript (GenBank U75214) encoding an EAACl protein with 148 residues truncated at N-terminal was cloned and named as EAAC2. Sequence analysis shows that EAAC2 has it's own start code and unique 5'UTR that is different from that of EAACl. A mouse genomic library was screened and a positive clone including EAACl CDS was sequenced (GenBank AF 322393) and indicates that normal EAACl transcript (GenBank U73521) is transcribed from 10 exons in terms of exon Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ, Ⅶ, Ⅷ,Ⅸ, Ⅹ, and EAAC2 transcript is consisted by exons from IV to IX as same as that of EAACl and with its unique exon β upstream to exon Ⅳ and exon δ downstream to IX. EAAC2 transcript has a cluster of transcriptional start sites not overlapping with the transcriptional start sites of EAACl. These results indicate that EAAC2 is transcribed from an independent promoter but not an alternative splicing event.
文摘Transgenic mice ubiquitously overexpressing murine γ aminobutyric acid transporter subtype Ⅰ were created. Unexpectedly, these mice markedly exhibited heritable obesity, which features significantly increased body weight and fat deposition. Behavioral examination revealed that transgeinc mice have slightly reduced spontaneous locomotive capacity and altered feeding pattern. Tills preliminary finding indicates that the inappropriate level of γ-aminobutyric acid transporters may be directly or indirectly involved in the pathogenic mechanism underlying certain types of obesity.
基金Supported by Shanghai Municipal Health Bureau FoundationNo.2010037+2 种基金the National Natural Science Foundation of ChinaNos.3090015681071444 and 31000986
文摘AIM: To generate a Gpr128 gene knockout mouse model and to investigate its phenotypes and the biological function of the Gpr128 gene.
文摘The norepinephrine transporter(NET) is a member of the Na+/Cl- dependent neurotransmitter transporter family and constitutes the target of several clinically important antidepressants. To delineate the critical amino acid residues and the function of C-terminal in regulating transport activity of NET, here we constructed two site mutants (V70F, F72V; V70I, F72V) and one C-terminal truncated mutant (△611-617). The wild type and mutants of NET were expressed in Xenopus oocytes by injection of their cRNA. We found that all of these mutants lost their transport activity. These results indicate that the amino acid residues of V70 and F72 3 and the last seven amino acids of C-terminal are essential to the transport activity of NET.
基金Supported by The Project of Shanghai Municipal Health Commission,No. 20214Y0223
文摘BACKGROUND The recognized pattern of cervical lymph node metastasis(CLNM)of papillary thyroid carcinoma involves a stepwise route.Contralateral lymph node skip metastasis is very rare.In addition,the patient in our case report also suffered from a breast carcinoma accompanied by left supraclavicular lymphadenopathy,which made it difficult to distinguish the origin of the CLNM.Based on this case,we recommended that more detailed physical and imaging examinations are needed for patients with uncommon cervical lymphatic metastasis of primary cancer.CASE SUMMARY A 53-year-old women was admitted to the hospital for a neck mass in the left cervical region that had existed for 2 mo.The neck mass was suspected to be an enlarged lateral LN originating from papillary thyroid microcarcinoma of the contralateral thyroid lobe,according to ultrasound and ultrasound-guided fine needle aspiration biopsy.The patient underwent total thyroidectomy and radical cervical LN dissection.Postoperative pathology confirmed the diagnosis of papillary thyroid microcarcinoma with contralateral lymphatic skip metastasis.Unfortunately,a breast cancer was discovered 4 mo later,which was accompanied by ipsilateral supraclavicular LN metastasis.She accepted neoadjuvant chemotherapy and subsequent left modified radical mastectomy for treatment.The patient is currently receiving postoperative radiotherapy,and no local recurrence was observed in the 6-mo follow-up after surgery.CONCLUSIONWe present a rare case of papillary thyroid microcarcinoma with contralateral lymphatic skipmetastasis and breast cancer with supraclavicular lymphatic metastasis.
文摘The human norepinephrine transporter(NET) gene was cloned and structurally analyzed. The far 5’ fragment containing exon 1 (a non-coding exon) and exon 2 was sequenced. The transcription start site of the gene in human brain stem tissue was determined by primer extension analysis. It was found that the gene could be transcribed from multiple starting points. The 5’ flanking sequence contains a proximal G-C rich region, one possible GSG elemeflt and several SP1 sites. However it does not contain TATA box and CAAT box motifS. Gel shift analysis with nuclear extracts from different tissues of mouse shows that the G-C rich region may be involved in tissue specific expression of the gene.
文摘A cDNA molecule encoding a major part of the hu-man Norepinephrine transporter(hNET) was synthesized by means of Polymerase Chain Reaction(PCR) technique and used as a probe for selecting the human genomic NET gene. A positive clone harbouring the whole gene was ob-tained from a human lymphocyte genomic library through utilizing the "genomic walking" technique. The clone, des-ignated as phNET, harbours a DNA fragment of about 59 kb in length inserted into BamH Ⅰ site in cosmid pWE15.The genomic clone contains 14 exons encoding all amino acid residues in the protein. A single exon encodes a dis-tinct transmembrane domaill, except for transmembrane domain 10 and 11, which are encoded by part of two ex-ons respectively, and exon 12, which encodes part of do-main 11 and all of domain 12. These results imply that there is a close relationship between exon splicing of a gene and structural domains of the protein, as is the case for the human γ-aminobutyric acid transporter(hGAT) and a number of other membrane proteins.
文摘DNA methyltransferase 3A (Dnmt3a), a de novo methyltransferase, has attracted a great deal of attention for its important role played in tumorigenesis. We have previously demonstrated that melanoma is unable to grow in-vivo in conditions of Dnmt3a depletion in a mouse model. In this study, we cultured the Dnmt3a depletion B16 melanoma (Dnmt3a-D) cell line to conduct a comparative analysis of protein expression con-comitant with Dnmt3a depletion in a melanoma cell line. After two-dimensional separation, by gel electro-phoresis and liquid chromatography, combined with mass spectrometry analysis (1DE-LC-MS/MS), the re-sults demonstrated that 467 proteins were up-regulated and 535 proteins were down-regulated in the Dnmt3a-D cell line compared to the negative control (NC) cell line. The Genome Ontology (GO) and KEGG pathway were used to further analyze the altered proteins. KEGG pathway analysis indicated that the MAPK signaling pathway exhibited a greater alteration in proteins, an interesting finding due to the close relation-ship with tumorigenesis. The results strongly suggested that Dnmt3a potentially controls the process of tu-morigenesis through the regulation of the proteins (JNK1, p38α, ERK1, ERK2, and BRAF) involved in tu-mor-related pathways, such as the MAPK signaling pathway and melanoma pathway.
文摘Background： The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin （DC-SIGN） in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases, but whether it takes place in renal tissues during hemorrhagic shock （HS） is unknown. The present study airned to investigate this phenomenon and the inhibitory effect of Vitamin C （VitC）. Methods： A Sprague Dawley rat HS model was established in vivo in this study. The expression level and location of DC-SIGN were observed in kidneys. Also, the degree of histological damage, the concentrations of tumor necrosis factor-or and interleukin-6 in the renal tissues, and the serum concentration of blood urea nitrogen and creatinine at different times （2-24 h） alter HS （six rats in each group）, with or without VitC treatment belbre resuscitation, were evaluated. Results： HS induced DC-SIGN expression in rat tubular epithelial cells. The proinflarnmatory cytokine concentration, histological damage scores, and functional injury of kidneys had increased. All these phenornena induced by HS were relieved when the rats were treated with VitC before resuscitation. Conclusions： The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN, and the levels of proinflarnmatory cytokines in the kidney tissues improved correspondingly. The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney.
基金grants from the National Natural Science Foundation of China (No.81430028)the Ministry of Science and Technology of China (No.2011BAI15B02)+1 种基金the grants from the Science and Technology Commission of Shanghai Municipality (Nos.13DZ2280600 and 15DZ2290800)the grant from Shanghai First People's Hospital Affiliated to Shanghai Jiao Tong University (No.81300776).
文摘Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated Rdh13 knockout mice and showed that Rdh13 deficiency causes severe acute retinal light damage. In this study, considering that Rdh13 is highly expressed in mouse liver, we further evaluated the potential effect of Rdh13 on liver injury induced by carbon tetrachloride (CC14). Although Rdh13 deficiency showed no significant effect on liver histology and physiological functions under regular culture, the Rdh13^-/- mice displayed an attenuated response to CCl4-induced liver injury. Their livers also exhibited less histological changes and contained lower levels of liver-related metabolism enzymes compared with the livers of wild-type (WT) mice. Furthermore, the Rdhl3 1 mice had Rdh13 deficiency and thus their liver cells were protected from apoptosis, and the quantity of their proliferative cells became lower than that in WT after CC14 exposure. The ablation of Rdhl3 gene decreased the expression levels of thyroid hormone-inducible nuclear protein 14 (Spot14) and cytochrome P450 (Cyp2el) in the liver, especially after CC14 treatment for 48 h. These data suggested that the alleviated liver damage induced by CC14 in Rdh13^-/- mice was caused by Cyp2el enzymes, which promoted reductive CC14 metabolism by altering the status of thyroxine metabolism. This result further implicated Rdhl3 as a potential drug target in preventing chemically induced liver injury.
