Characterization of somatostatin transactivating factor-1, a novel homeobox factor that stimulates somatostatin expression in pancreatic islet cells.
Characterization of somatostatin transactivating factor-1, a novel homeobox factor that stimulates somatostatin expression in pancreatic islet cells.
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DOI：
10.1210/mend.7.10.7505393
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发表时间：
1993-10
影响因子：
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通讯作者：
J. Leonard;Bernard Peers;T. Johnson;K. Ferreri;Soon Lee;M. Montminy
中科院分区：
文献类型：
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作者：
J. Leonard;Bernard Peers;T. Johnson;K. Ferreri;Soon Lee;M. Montminy
内分泌胰腺由几种分化的细胞类型组成，这些细胞类型的区别在于它们选择性表达肽激素，如胰岛素、胰高血糖素和生长抑素。虽然已经提出了一些同源异型因子作为胰腺中单个肽基因的关键调节因子，但它们的细胞分布和相对丰度仍然没有表征。此外，它们重叠的DNA结合特异性进一步模糊了这些因子在发育过程中的调节功能。在这份报告中，我们描述了一种新的同源异型生长抑素反式激活因子称为STF-1，这是均匀的内分泌胰腺和小肠的细胞中表达。由283个氨基酸组成的STF-1蛋白与生长抑素启动子内的组织特异性元件结合，并在体内和体外刺激生长抑素基因表达。值得注意的是，STF-1在产生生长激素抑制素的胰岛细胞的核提取物中具有主要的组织特异性元素结合活性，这表明该蛋白质可能在调节肽激素表达和指定发育肠道中的内分泌细胞谱系方面发挥主要作用。
The endocrine pancreas consists of several differentiated cell types that are distinguished by their selective expression of peptide hormones such as insulin, glucagon, and somatostatin. Although a number of homeobox-type factors have been proposed as key regulators of individual peptide genes in the pancreas, their cellular distribution and relative abundance remain uncharacterized. Also, their overlapping DNA binding specificities have further obscured the regulatory functions these factors perform during development. In this report we characterize a novel homeobox-type somatostatin transactivating factor termed STF-1, which is uniformly expressed in cells of the endocrine pancreas and small intestine. The 283-amino acid STF-1 protein binds to tissue-specific elements within the somatostatin promoter and stimulates somatostatin gene expression both in vivo and in vitro. Remarkably, STF-1 comprises the predominant tissue-specific element-binding activity in nuclear extracts from somatostatin-producing pancreatic islet cells, suggesting that this protein may have a primary role in regulating peptide hormone expression and specifying endocrine cell lineage in the developing gut.