A rat gastrin-human gastrin chimeric transgene directs antral G cell-specific expression in transgenic mice.
A rat gastrin-human gastrin chimeric transgene directs antral G cell-specific expression in transgenic mice.
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大鼠胃泌素-人胃泌素嵌合转基因指导转基因小鼠胃窦 G 细胞特异性表达。
DOI：
10.1152/ajpgi.1995.268.6.g1025
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Schmidt,EV
中科院分区：
文献类型：
--
作者：
Wang,TC;Babyatsky,MW;Oates,PS;Zhang,Z;Tillotson,L;Chulak,M;Brand,SJ;Schmidt,EV
胃肠道中胃泌素基因的表达受到发育和空间调节。在成熟动物中，胃泌素是壁酸分泌的重要调节剂，主要在胃窦的 G 细胞中表达。为了确定特定的启动子元件是否可以在体内指导表达到胃窦，克隆了近端大鼠胃泌素启动子的450个核苷酸，并用于构建大鼠胃泌素-人胃泌素报告基因嵌合转基因，将其注射到小鼠种系中。 Northern印迹分析、原位杂交和双标记免疫细胞化学研究证明转基因在胃窦G细胞中特异性表达。在回肠和结肠中观察到低水平的转基因表达，免疫组织化学研究表明在表达肽 YY 的肠内分泌细胞中存在共定位。同样的 450 个核苷酸的大鼠胃泌素启动子，当与人类生长激素基因连接时，不会导致胃窦表达。类似地，人胃泌素-人胃泌素报告基因转基因也没有实现胃窦表达，尽管它确实在肝脏中表达。这些结果表明，基础450个核苷酸的大鼠胃泌素启动子和人胃泌素基因的基因内序列中存在的顺式作用元件对于指导转基因特异性表达至胃窦G细胞是必需的。
Gastrin gene expression in the gastrointestinal tract is under both developmental and spatial regulation. In the mature animal, gastrin, an important regulator of parietal acid secretion, is expressed primarily in G cells of the antrum. To determine whether specific promoter elements can direct expression to the gastric antrum in vivo, 450 nucleotides of the proximal rat gastrin promoter were cloned and used to construct a rat gastrin-human gastrin reporter chimeric transgene, which was injected into the mouse germ line. Northern blot analysis, in situ hybridization, and double-label immunocytochemistry studies demonstrated expression of the transgene specifically in antral G cells. Low levels of transgene expression were observed in the ileum and colon, where immunohistochemical studies demonstrated colocalization in enteroendocrine cells expressing peptide YY. The same 450-nucleotide rat gastrin promoter, when joined to the human growth hormone gene, did not result in antral expression. Similarly, a human gastrin-human gastrin reporter transgene also did not achieve antral expression, although it did express in the liver. These results suggest that cis-acting elements present in both the basal 450-nucleotide rat gastrin promoter and the intragenic sequences of the human gastrin gene are necessary to direct expression of a transgene specifically to antral G cells.