Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of str...Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of structure and expression of the transgene, accurate extrachromosomal homologous recombination (ECR) between the two overlapping DNA fragments was found. Different levels of CAT activity were detected in milk from these lines. The highest CAT activity was about 25-50μg/mL milk. In some mice. CAT activity was found in salvia gland, thymus and spleen extracts. The high frequency and accuracy of ECR reported here will be applicable in the experimental manipulation for generation of relatively large transgene.展开更多
DNA of human cytomegalovirus (HCMV) contains three transforming fragments, which have been mapped in the long unique region of the viral genome(see Fig.1). A minimal region of 558 base pairs(bp) (pCM4127) was localize...DNA of human cytomegalovirus (HCMV) contains three transforming fragments, which have been mapped in the long unique region of the viral genome(see Fig.1). A minimal region of 558 base pairs(bp) (pCM4127) was localized in the XbaI-Hindlll fragment of HCMV strain AD169 (mapunit 0.123—0.140)and designated morphological transforming region Ⅰ (mtrⅠ). MtrⅠwas reported to cause one-step focal transformation of primary展开更多
基金Project supported by the National Gongguan Program.
文摘Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of structure and expression of the transgene, accurate extrachromosomal homologous recombination (ECR) between the two overlapping DNA fragments was found. Different levels of CAT activity were detected in milk from these lines. The highest CAT activity was about 25-50μg/mL milk. In some mice. CAT activity was found in salvia gland, thymus and spleen extracts. The high frequency and accuracy of ECR reported here will be applicable in the experimental manipulation for generation of relatively large transgene.
文摘DNA of human cytomegalovirus (HCMV) contains three transforming fragments, which have been mapped in the long unique region of the viral genome(see Fig.1). A minimal region of 558 base pairs(bp) (pCM4127) was localized in the XbaI-Hindlll fragment of HCMV strain AD169 (mapunit 0.123—0.140)and designated morphological transforming region Ⅰ (mtrⅠ). MtrⅠwas reported to cause one-step focal transformation of primary