Sakamoto N, Saiga H, Yasugi S
Department of Biology, Faculty of Science, Tokyo Metropolitan University, Japan.
Biochem Biophys Res Commun. 1998 Sep 18;250(2):420-4. doi: 10.1006/bbrc.1998.9290.
Three groups of pepsinogens exist in vertebrates, namely, pepsinogen A, pepsinogen C, and prochymosin, which are produced at different developmental stages. In the chicken, prochymosin is expressed only in the embryonic stage, while pepsinogens A and C are secreted from adult chicken proventricular (glandular stomach) mucosa. In order to understand the mechanism of transcriptional regulation of these genes, we have cloned the genes encoding chicken pepsinogens A and C and analyzed the sequences possibly involved in their regulation. 5'-Upstream sequences of both genes contain putative binding motifs for transcription factors such as GATA, Sox, and HNF-3 beta, which are expressed in the chicken gut epithelium. Moreover, we found seven putative binding motifs for human MZF-1 in intron 8 of pepsinogen A gene. These transcription factors may act as regulators of expression of chicken pepsinogen genes.
脊椎动物体内存在三类胃蛋白酶原，即胃蛋白酶原A、胃蛋白酶原C和凝乳酶原，它们在不同的发育阶段产生。在鸡体内，凝乳酶原仅在胚胎期表达，而胃蛋白酶原A和C则由成年鸡腺胃黏膜分泌。为了了解这些基因的转录调控机制，我们克隆了编码鸡胃蛋白酶原A和C的基因，并分析了可能参与其调控的序列。这两个基因的5'上游序列包含转录因子如GATA、Sox和HNF-3β的假定结合基序，这些转录因子在鸡肠道上皮中表达。此外，我们在胃蛋白酶原A基因的第8内含子中发现了7个人类MZF-1的假定结合基序。这些转录因子可能作为鸡胃蛋白酶原基因表达的调节因子。
