title: Regulation of expression of a sheep metallothionein 1a-sheep growth hormone fusion gene in transgenic mice.
abstract: Transgenic mice containing a sheep metallothionein 1a-sheep growth hormone fusion gene exhibited low, tissue-specific basal levels of transgene mRNA expression, resulting in slightly elevated levels of circulating growth hormone that did not lead to a detectable increase in growth. After zinc stimulation, high levels of transgene mRNA expression were induced in a number of tissues; these levels correlated with increased levels of circulating growth hormone, resulting in growth increases of up to 1.5 times the levels of controls and unstimulated transgenic mice. After removal of the zinc stimulus, transgene expression and circulating growth hormone concentrations returned to basal levels. Additional evidence from the pattern of developmental expression of the transgene suggests that zinc is the main regulator of this promoter in mice. The demonstrated regulation and low basal level of expression of the sheep metallothionein 1a promoter make it a candidate for use in other mouse transgenic studies and for use in transgenic livestock, in which regulation of expression is essential.
authors: Division of Animal Production, Commonwealth Scientific and Industrial Research Organization, Blacktown, New South Wales, Australia.
authors: C M
authors: CM
authors: Shanahan
authors: N W
authors: NW
authors: Rigby
authors: J D
authors: JD
authors: Murray
authors: J T
authors: JT
authors: Marshall
authors: C A
authors: CA
authors: Townrow
authors: C D
authors: CD
authors: Nancarrow
authors: K A
authors: KA
authors: Ward
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D005260:Female; D005786:Gene Expression Regulation; D005796:Genes / Q000187:drug effects; D013006:Growth Hormone / Q000096:biosynthesis / Q000097:blood / Q000235:genetics*; D008297:Male; D008668:Metallothionein / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008822:Mice, Transgenic / Q000254:growth & development*; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000032:analysis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D015183:Restriction Mapping; D012756:Sheep; D014158:Transcription, Genetic; D015032:Zinc / Q000494:pharmacology
chemical_list: D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D012313:RNA; D013006:Growth Hormone; D008668:Metallothionein; D015032:Zinc