Expression of human growth hormone in the milk of transgenic rabbits with transgene mapped to the telomere region of chromosome 7q.
The advent of transgenic technology has provided methods for the production of pharmaceuticals by the isolation of these proteins from transgenic animals. The mammary gland has been focused on as a bioreactor, since milk is easily collected from lactating animals and protein production can be expressed at very high levels, including hormones and enzymes. We demonstrate here the expression pattern of recombinant human growth hormone (rhGH) in transgenic rabbits carrying hGH genomic sequences driven by the rat whey acidic protein (WAP) promoter. The transgene was mapped to the q26-27 telomere region of chromosome 7q by fluorescence in situ hybridization (FISH). Nearly 30 % of the F1 generation demonstrated the presence of transgene. The recombinant growth hormone was detected in the milk of the transgenic rabbit females, but not in serum, up to the level of 10 μg/ml. Ectopic expression of the transgene in the brain, heart, kidney, liver, and salivary gland was not observed, indicating that a short sequence of rat WAP promoter (969 bp) contained essential sequences directing expression exclusively to the mammary gland. The biological activity of recombinant growth hormone was measured by immunoreactivity and the capability to stimulate growth of the hormone-dependent Nb211 cell line.
Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632, Poznan, Poland.
Daniel
D
Lipinski
Joanna
J
Zeyland
Marlena
M
Szalata
Andrzej
A
Plawski
Malgorzata
M
Jarmuz
Jacek
J
Jura
Aleksandra
A
Korcz
Zdzislaw
Z
Smorag
Marek
M
Pienkowski
Ryszard
R
Slomski
D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics / Q000378:metabolism*; D002874:Chromosome Mapping / Q000379:methods*; D033481:Chromosomes, Mammalian; D005260:Female; D005786:Gene Expression Regulation; D019382:Human Growth Hormone / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D015592:Immunoradiometric Assay; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008321:Mammary Glands, Animal / Q000737:chemistry; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D011817:Rabbits; D051381:Rats; D016615:Telomere / Q000235:genetics*; D019076:Transgenes
D008894:Milk Proteins; C024471:whey acidic proteins; D019382:Human Growth Hormone