Co-integration and expression of bacterial and genomic transgenes in the pancreatic and intestinal tissues of transgenic mice.
Previous studies in the mammary gland have reported the 'rescue' of poorly expressed cDNA transgenes by their co-integration with a genomic sequence specifically expressed in the mammary tissue. To determine whether a highly expressed genomic sequence co-integrated with a cDNA sequence can rescue expression in other tissues, the expression of a bacterial gene, celE', encoding endoglucanase E' (EGE'), was investigated in the pancreatic and intestinal epithelia of transgenic mice. To rescue pancreatic expression, the human growth hormone genomic sequence was co-integrated with the bacterial gene, whereas to rescue intestinal expression, the genomic sequence encoding the intestinal fatty acid binding protein was used. In both studies the number of transgenics expressing celE' was significantly increased (60%) by the use of a genomic sequence, but only in the intestinal tissues was the level of celE' expression improved. However, this improvement was modest, representing at maximum only a doubling in the levels of EGE'. Thus permissive integration or rescue may be general, but the overall level of rescue is often insubstantial compared to the endogenous expression of the transgene genomic DNA.
Ali
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S
Department of Biological and Nutritional Sciences, University of Newcastle upon Tyne, UK.
Fontes
C M
CM
Hazlewood
G P
GP
Hirst
B H
BH
Clark
A J
AJ
Gilbert
H J
HJ
Hall
J
J
D000818:Animals; D015152:Blotting, Northern; D002352:Carrier Proteins / Q000235:genetics; D002480:Cellulase / Q000235:genetics; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D018014:Gene Transfer Techniques; D019382:Human Growth Hormone / Q000235:genetics; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D008845:Microinjections; D018996:Myelin P2 Protein / Q000235:genetics; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D010179:Pancreas / Q000378:metabolism*; D010196:Pancreatic Elastase / Q000235:genetics; D051381:Rats; D019076:Transgenes; D025521:Tumor Suppressor Proteins
D002352:Carrier Proteins; C107608:FABP7 protein, human; C082667:Fabp5 protein, mouse; C086936:Fabp7 protein, mouse; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D025521:Tumor Suppressor Proteins; D019382:Human Growth Hormone; D002480:Cellulase; D010196:Pancreatic Elastase