Abstract: The mammary gland-specific expression systems developed by the present inventors, named pGbc, pGbc_L and pGbc_S were deposited under the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for the Purpose of Patent Procedure in the Korean Collection for Type Cultures (KCTC), Korean Research Institute of Bioscience and Biotechnology at 52, Oun-dong, Yusong-Ku, Taejon 305–333, Republic of Korea, on Aug. 17, 1998, and the accession deposit Nos. KCTC 0515BP, 0514BP and 0513BP were issued, respectively. All restructions on the availability to the public of the deposited materials will be irrevocably removed upon the granting of a patent.

Abstract: There are disclosed mammary gland tissue-specific expression systems using the promoter site for the &bgr;-casein gene of Korean native goats, by use of which physiological activating substances can be produced. In each of the expression systems, that is, novel plasmids pGbc, pGbc_L and pGbc_S (deposition Nos. KCTC 0515BP, 0514BP and 0513BP, respectively), a &bgr;-casein gene expression-regulating region, a physiological activating substance gene and a termination-regulating region are linked. Human granulocyte colony stimulating factor (hG-CSF) or human granulocyte macrophage colony stimulating factor (hGM-CSF) can be produced in HC11 cells, a mouse mammary gland tissue-derived cell line, and in the milk secreted from the transgenic mice by use of a hG-CSF or hGM-CSF gene-carrying pGbc, pGbc_L or pGbc_S in transfection into cell and microinjection to mouse. The proteins are those which experience the posttranslational modification and maintain their normal activity in the human body.

Abstract: There are disclosed mammary gland tissue-specific expression systems using the promoter site for the &bgr;-casein gene of Korean native goats, by use of which physiological activating substances can be produced. In each of the expression systems, that is, novel plasmids pGbc, pGbc_L and pGbc_S (deposition Nos. KCTC 0515BP, 0514BP and 0513BP, respectively), a &bgr;-casein gene expression-regulating region, a physiological activating substance gene and a termination-regulating region are linked. Human granulocyte colony stimulating factor (hG-CSF) or human granulocyte macrophage colony stimulating factor (hGM-CSF) can be produced in HC11 cells, a mouse mammary gland tissue-derived cell line, and in the milk secreted from the transgenic mice by use of a hG-CSF or hGM-CSF gene-carrying pGbc, pGbc_L or pGbc_S in transfection into cell and microinjection to mouse. The proteins are those which experience the posttranslational modification and maintain their normal activity in the human body.

Abstract: A transgenic goat zygote is developed from a goat zygote comprising a nucleic acid construct containing a nucleotide sequence of a goat &bgr;-casein promoter and a nucleotide sequence encoding hG-CSF, which produces milk containing a high concentration of biologically active hG-CSF.