摘要
将编码人组织型纤溶酶原激活剂（ｔＰＡ） 的１７６６ｂｐ 基因片段插入大鼠β－乳酪蛋白 （β－Ｃａｓｅｉｎ） 启动子的下游及ｐＳＶＬ质粒的ＰｏｌｙＡ上游。构建了ｐβ－Ｃａｓｅｉｎ－ＰＡ１、ｐβ－Ｃａｓｅｉｎ－ＰＡ２ 两个乳腺定位表达载体。将其分别与脂质体混合制备转染液后， 直接注入妊娠２９ 天的青紫蓝母兔乳腺中。结果表明：两种载体均能在乳腺中表达，且具有溶纤活性，表达量在２００—５００ｎｇ／ｍ ｌ之间。这不仅证明了所构建载体可用于转基因乳腺生物反应器的建立， 而且提示，
The human tissue plasminogen activator (tPA) cDNA with the length of 1766bp gene which encodes the complete tPA was inserted into the downstream of rat beta casein and upstream of the poly(A) of pSVL plasmid to construct mammary gland expressing vectors. The DNA/liposome complex was injected into mammary glands of pregnant rabbit through duct of mammary gland. The results showed that both of the two vectors could efficiently express tPA with the activities of lysis of fibrin clot in the milk. The expressing quantity was between 200-500ng/ml. These results showed that these two vectors could be expressed in cells of mammary gland in high level and they could be used to establish transgenic animals. It also suggested that the direct injection of gene into mammary gland may become a simple and efficient method to produce proteins with biological activities.
出处
《高技术通讯》
EI
CAS
CSCD
1999年第10期52-56,共5页
Chinese High Technology Letters
基金
863计划资助
