A novel mitogenic protein that is highly expressed in cells of the gastric antrum mucosa
A novel mitogenic protein that is highly expressed in cells of the gastric antrum mucosa
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DOI：
10.1152/ajpgi.00453.2002
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发表时间：
2003-08-01
影响因子：
4.5
通讯作者：
Toback, FG
中科院分区：
文献类型：
--
作者：
Martin, TE;Powell, CT;Toback, FG
人类和猪的新型胃蛋白 cDNA 已得到表征，该蛋白是一种在胃窦粘膜细胞中高水平表达的基因的产物。基因组 DNA 的一般外显子/内含子结构在人类和小鼠中是保守的。人类和小鼠 mRNA 的预测蛋白质序列分别包含 185 个和 184 个氨基酸。从猪胃提取物中分离出的蛋白质具有 NH2 末端，与 20 个氨基酸信号肽的裂解一致。人类 cDNA 在大肠杆菌中表达，产生用于抗体生产的蛋白质抗原。抗体在所有测试的哺乳动物物种的胃窦提取物中检测到 18 kDa 的多肽。免疫细胞化学将胃窦粘膜蛋白 (AMP)-18 定位于小鼠胃窦的表面粘膜细胞，特别是分泌颗粒，表明它与粘蛋白共同分泌。胃窦提取物和重组人 AMP-18 对上皮细胞具有促进生长的活性，这种活性可以被特异性抗血清阻断。我们认为AMP-18是一种维持胃粘膜上皮完整性的“胃因子”。
Human and pig cDNAs for a novel stomach protein, the product of a gene expressed at high levels specifically in cells of the antrum mucosa, have been characterized. The general exon/intron structure of the genomic DNA is conserved in humans and mice. The predicted protein sequences of the human and mouse mRNAs contain 185 and 184 amino acids, respectively. The protein isolated from pig antral extracts has an NH2 terminus consistent with cleavage of a 20-amino acid signal peptide. Human cDNA was expressed in E. coli to generate a protein antigen for antibody production. The antibodies detected polypeptides of 18 kDa in antrum extracts from all mammalian species tested. Immunocytochemistry located antrum mucosal protein (AMP)-18 to surface mucosal cells of the mouse antrum and, specifically, to secretion granules, suggesting that it is cosecreted with mucins. Antrum extracts and recombinant human AMP-18 exhibit growth-promoting activity on epithelial cells that can be blocked by the specific antisera. We suggest that AMP-18 is a "gastrokine" that maintains the integrity of the gastric mucosal epithelium.