Familari M, Cook G A, Taupin D R, Marryatt G, Yeomans N D, Giraud A S
The University of Melbourne, Department of Medicine, Western Hospital, Footscray, Australia.
Int J Dev Biol. 1998 Sep;42(6):783-9.
Trefoil peptides are members of a unique family of proteins found predominately throughout the gastrointestinal tract, whose proposed functions include mucus stabilization, stimulation and/or differentiation of epithelial cells during wound repair. Recent trefoil knockout studies have reported delays in epithelial cell migration or maturation pathways together with almost a complete lack of mucus. In order to fully explore the role of trefoil peptides in gastrointestinal maturation, these studies were undertaken to accurately characterize the expression of trefoil peptides in the developing rat gut. The results of RPA suggest that trefoil mRNA's are expressed as early as 15 days post coitus (dpc) in the intestine and stomach. Proteins are detected at 17 dpc by radioimmunoassay and immunohistochemical studies, which localize trefoil peptide expression to the lumenal surface of epithelial cells. At 17 dpc the gut is lined by pseudo-stratified, undifferentiated epithelial cells. Polarized, columnar cells are not detected until at least 18 dpc, with sparse mucus staining and parietal cell markers not being detected until 18 and 19 dpc respectively. This data demonstrates that trefoil peptides are early markers of epithelial cell maturation in the developing rat gut. The time course of their expression, well before the mucus cell type is specified, suggests a potential role in epithelial cell differentiation.
三叶肽是一类独特蛋白质家族的成员，主要存在于整个胃肠道，其推测的功能包括在伤口修复过程中稳定黏液、刺激和/或分化上皮细胞。最近的三叶肽基因敲除研究报告称，上皮细胞迁移或成熟途径出现延迟，同时几乎完全缺乏黏液。为了全面探究三叶肽在胃肠道成熟过程中的作用，开展了这些研究以准确描述三叶肽在发育中的大鼠肠道中的表达情况。核糖核酸酶保护分析（RPA）结果表明，三叶肽信使核糖核酸（mRNA）早在交配后15天（dpc）就在肠道和胃中表达。通过放射免疫分析和免疫组织化学研究在17 dpc检测到蛋白质，这些研究将三叶肽表达定位在上皮细胞的腔面。在17 dpc时，肠道由假复层未分化上皮细胞构成。直到至少18 dpc才检测到极化的柱状细胞，直到18 dpc和19 dpc才分别检测到稀疏的黏液染色和壁细胞标记物。该数据表明，三叶肽是发育中的大鼠肠道上皮细胞成熟的早期标志物。它们的表达时间进程远早于黏液细胞类型确定的时间，提示其在上皮细胞分化中可能发挥作用。
