A cosmid construct μLCRAγψβδβ were induced into mouse erythroleukemia cell lines 585 that expresses murine adult globin only and MEL GM 979 that expresses both murine embryonic and ad...A cosmid construct μLCRAγψβδβ were induced into mouse erythroleukemia cell lines 585 that expresses murine adult globin only and MEL GM 979 that expresses both murine embryonic and adult globins.Similar patterns of human globin gene expression were displayed in the two MEL cell lines transfected with the construct.Inducible expression of the Aγ and β gene was observed during induced cell differentiation.However,the expression level of the Aγ globin gene is much higher than that of the β globin gene in either uninduced or induced MEL transformants.No γ to β switching happened in the stable MEL transformants following a continuous culture.The much more effective enhance of the μLCR on the Aγ globin gene than that on the β globin gene is resulted probably from the fact that the distance between the LCR and the β globin gene is much longer than that between the LCR and the Aγ globin gene in the construct,in comparison with other constructs containing HS2 or μLCR linked to both of γ and β globin genes in different order.Two suggestions can be derived from these results:1) A competition between the γ and β globin gene for interaction with the LCR may indeed present,but only an enough long distance difference between the LCR to the γ and to the β gene can effectively influence the competition;2) Unlike transgenic mice,MEL cells are incapable of reconstructing the regulatory information involved in developmental control when it is provided by a fragment of the β globin gene cluster with limited length.展开更多
Severe acute respiratory syndrome(SARS)emerged in 2002 as a severe and highly contagious infectious disease that rapidly spread to a number of different countries.The collaborative efforts of the global scientific com...Severe acute respiratory syndrome(SARS)emerged in 2002 as a severe and highly contagious infectious disease that rapidly spread to a number of different countries.The collaborative efforts of the global scientific community have provided,within a short period of time,substantial insights into the molecular biology and immunology of SARS-CoV.Although the outbreak has been contained,there is continuous concern that the virus may resurface into the human population through seasonal changes,animal reservoirs or laboratory accidents.The severe morbidity and mortality associated with SARS make it imperative that an effective vaccine be developed to prevent reemergence and epidemics in the future.Cellular & Molecular Immunology.2005;2(2):101-105.展开更多
文摘A cosmid construct μLCRAγψβδβ were induced into mouse erythroleukemia cell lines 585 that expresses murine adult globin only and MEL GM 979 that expresses both murine embryonic and adult globins.Similar patterns of human globin gene expression were displayed in the two MEL cell lines transfected with the construct.Inducible expression of the Aγ and β gene was observed during induced cell differentiation.However,the expression level of the Aγ globin gene is much higher than that of the β globin gene in either uninduced or induced MEL transformants.No γ to β switching happened in the stable MEL transformants following a continuous culture.The much more effective enhance of the μLCR on the Aγ globin gene than that on the β globin gene is resulted probably from the fact that the distance between the LCR and the β globin gene is much longer than that between the LCR and the Aγ globin gene in the construct,in comparison with other constructs containing HS2 or μLCR linked to both of γ and β globin genes in different order.Two suggestions can be derived from these results:1) A competition between the γ and β globin gene for interaction with the LCR may indeed present,but only an enough long distance difference between the LCR to the γ and to the β gene can effectively influence the competition;2) Unlike transgenic mice,MEL cells are incapable of reconstructing the regulatory information involved in developmental control when it is provided by a fragment of the β globin gene cluster with limited length.
文摘Severe acute respiratory syndrome(SARS)emerged in 2002 as a severe and highly contagious infectious disease that rapidly spread to a number of different countries.The collaborative efforts of the global scientific community have provided,within a short period of time,substantial insights into the molecular biology and immunology of SARS-CoV.Although the outbreak has been contained,there is continuous concern that the virus may resurface into the human population through seasonal changes,animal reservoirs or laboratory accidents.The severe morbidity and mortality associated with SARS make it imperative that an effective vaccine be developed to prevent reemergence and epidemics in the future.Cellular & Molecular Immunology.2005;2(2):101-105.
