ISSN:
1573-9368
Keywords:
bovine αS1-casein gene
;
DNA methylation
;
transgenic mice
;
mammary gland
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract In the lactating cow, mammary gland-specific hypomethylation occurs at twoHpa II sites in the 5′-flanking region of the αS1-casein gene, and one in the 3′-region. These sites, A, B. and C, are at nucleotide position −1388, −774 and +18034, respectively, relative to the major transcription start site. Site B was hypomethylated when the αS1-casein gene was expressed, and methylated when not expressed. In transgenic mice containing the bovine αS1-casein 5′ and 3′ regulatory elements fused to the human lactoferrin (hLF) cDNA, in some cases similar methylation patterns of sites A and B, as compared to the situation in the cow, were observed. In five mouse lines (out of the seven analysed) expressing the transgene in the milk, site B was hypomethylated in the mammary gland, while it was methylated in liver. In the two other mouse lines, no correlation was found between transgene expression and mammary gland-specific hypomethylation of site B. One of the five mouse lines with transgene expression and showing mammary-gland-specific hypomethylation of site B was studied in detail. In this mouse line, induction of transgene expression preceded hypomethylation of site B.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01980207
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