AIM： To approach the elusive function of the SLA/LP molecule, we have characterized genomic organization and conservation of the major antigenic and functional properties of the SLA/LP molecule in various species. ME...AIM： To approach the elusive function of the SLA/LP molecule, we have characterized genomic organization and conservation of the major antigenic and functional properties of the SLA/LP molecule in various species. METHODS： By means of computational biology, we have characterized the complete SLA/LP gene, mRNA and deduced protein sequences in man, mouse, zebrafish, fly, and worm. RESULTS： The human SLA/LP gene sequence of approximately 39 kb, which maps to chromosome 4p15.2, is organized in 11 exons, of which 10 or 11 are translated, depending on the splice variant. Homologous molecules were identified in several biological model organisms. The various homologous protein sequences showed a high degree of similarity or homology, notably at those residues that are of functional importance. The only domain of the human protein sequence that lacks significant homology with homologous sequences is the major antigenic epitope recognized by autoantibodies from autoimmune hepatitis （AIH） patients. CONCLUSION： The SLA/LP molecule and its functionally relevant residues have been highly conserved throughout the evoluti n, suggesting an indispensable function of the molecule. The finding that the only non-conserved domain is the dominant antigenic epitope of the human SLA/LP sequence, suggests that SLA/LP autoimmunity is autoantigen-driven rather than being driven by molecular mimicry.展开更多
AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/ reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury. METHODS...AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/ reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury. METHODS: Heterotopic segmental small bowel transplantation was performed in six rats with a sham operation and they were used as controls. Total RNA was extracted from the allografts (experimental group) and normal intestines (control group) 1 h after cold preservation/ reperfusion, and then purified to mRNA, which was then reversely transcribed to cDNA, and labeled with fluorescent Cy5-dUTP and Cy3-dUTP to prepare hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the fluorescent signals on cDNA microarray chip were scanned and analyzed. RESULTS: Among the 4 096 target genes, 82 differentially expressed genes were identified between the two groups. There were 18 novel genes, 33 expression sequence tags, and 31 previously reported genes. The selected genes may be divided into four classes: genes modulating cellular adhesion, genes regulating cellular energy, glucose and protein metabolism, early response genes and other genes. CONCLUSION: A total of 82 genes that may be relevant to cold preservation/reperfusion injury in small intestinal allografts are identified. Abnormal adhesion between polymorphonuclears and endothelia and failure in energy, glucose and protein metabolism of the grafts may contribute to preservation/reperfusion injury. The functions of the novel genes identified in our study need to be clarified further.展开更多
Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 ...Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 weeks. After blood glucose met the criteria of diabetes(over 16.7 mmol/L), mice were randomly divided into 3 groups: a control group(without any treatment), a rosiglitazone group(treated with rosiglitazone 12.5 mg/kg·d once per day), and a metformin group(treated with metformin 3 g/kg·d twice daily). After 4 weeks, we then determined the expression of PTEN and phosphoserine 473-Akt(pS473-Akt) in the epididymal adipose tissue with Western blots. The mice in each group were further divided into the insulin(-) subgroup and insulin(+) subgroup, which were intraperitoneally injected with saline and insulin(5 mU/g body weight), respectively. Results The expression of PTEN was elevated in the epididymal adipose tissue obtained from KKAy diabetic mice compared with that from the C57BL/6J mice(P<0.001). In accordance with the enhanced expression of PTEN, the level of pS473-Akt stimulated by insulin was decreased in the adipose tissue of KKAy mice compared to the C57BL/6J mice(P<0.001). Treatment with the insulin-sensitizing agents, rosiglitazone and metformin did not inhibit the elevated expression of PTEN in adipose tissue of KKAy diabetic mice. Conclusion PTEN may play an important role in the development of insulin resistance in adipose tissue of type 2 diabetes mice model.展开更多
基金Supported by the Deutsche Forschungsgemeinschaft(SFB 548)
文摘AIM： To approach the elusive function of the SLA/LP molecule, we have characterized genomic organization and conservation of the major antigenic and functional properties of the SLA/LP molecule in various species. METHODS： By means of computational biology, we have characterized the complete SLA/LP gene, mRNA and deduced protein sequences in man, mouse, zebrafish, fly, and worm. RESULTS： The human SLA/LP gene sequence of approximately 39 kb, which maps to chromosome 4p15.2, is organized in 11 exons, of which 10 or 11 are translated, depending on the splice variant. Homologous molecules were identified in several biological model organisms. The various homologous protein sequences showed a high degree of similarity or homology, notably at those residues that are of functional importance. The only domain of the human protein sequence that lacks significant homology with homologous sequences is the major antigenic epitope recognized by autoantibodies from autoimmune hepatitis （AIH） patients. CONCLUSION： The SLA/LP molecule and its functionally relevant residues have been highly conserved throughout the evoluti n, suggesting an indispensable function of the molecule. The finding that the only non-conserved domain is the dominant antigenic epitope of the human SLA/LP sequence, suggests that SLA/LP autoimmunity is autoantigen-driven rather than being driven by molecular mimicry.
基金Supported by the National Natural Science Foundation of China,No. 30271275
文摘AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/ reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury. METHODS: Heterotopic segmental small bowel transplantation was performed in six rats with a sham operation and they were used as controls. Total RNA was extracted from the allografts (experimental group) and normal intestines (control group) 1 h after cold preservation/ reperfusion, and then purified to mRNA, which was then reversely transcribed to cDNA, and labeled with fluorescent Cy5-dUTP and Cy3-dUTP to prepare hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the fluorescent signals on cDNA microarray chip were scanned and analyzed. RESULTS: Among the 4 096 target genes, 82 differentially expressed genes were identified between the two groups. There were 18 novel genes, 33 expression sequence tags, and 31 previously reported genes. The selected genes may be divided into four classes: genes modulating cellular adhesion, genes regulating cellular energy, glucose and protein metabolism, early response genes and other genes. CONCLUSION: A total of 82 genes that may be relevant to cold preservation/reperfusion injury in small intestinal allografts are identified. Abnormal adhesion between polymorphonuclears and endothelia and failure in energy, glucose and protein metabolism of the grafts may contribute to preservation/reperfusion injury. The functions of the novel genes identified in our study need to be clarified further.
基金Supported by National Natural Science Foundation of China(81270878)National Key Program of Clinical Science of China(WBYZ2011-873)
文摘Objective To investigate the expression of phosphatase and tension homolog(PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes. Methods KKAy diabetic mice were fed with high fat diet for 4 weeks. After blood glucose met the criteria of diabetes(over 16.7 mmol/L), mice were randomly divided into 3 groups: a control group(without any treatment), a rosiglitazone group(treated with rosiglitazone 12.5 mg/kg·d once per day), and a metformin group(treated with metformin 3 g/kg·d twice daily). After 4 weeks, we then determined the expression of PTEN and phosphoserine 473-Akt(pS473-Akt) in the epididymal adipose tissue with Western blots. The mice in each group were further divided into the insulin(-) subgroup and insulin(+) subgroup, which were intraperitoneally injected with saline and insulin(5 mU/g body weight), respectively. Results The expression of PTEN was elevated in the epididymal adipose tissue obtained from KKAy diabetic mice compared with that from the C57BL/6J mice(P<0.001). In accordance with the enhanced expression of PTEN, the level of pS473-Akt stimulated by insulin was decreased in the adipose tissue of KKAy mice compared to the C57BL/6J mice(P<0.001). Treatment with the insulin-sensitizing agents, rosiglitazone and metformin did not inhibit the elevated expression of PTEN in adipose tissue of KKAy diabetic mice. Conclusion PTEN may play an important role in the development of insulin resistance in adipose tissue of type 2 diabetes mice model.
