Woodbury R G, Gruzenski G M, Lagunoff D
Proc Natl Acad Sci U S A. 1978 Jun;75(6):2785-9. doi: 10.1073/pnas.75.6.2785.
An intracellular serine protease, which is believed to initiate the degradation of several intracellular pyridoxal phosphate-dependent enzymes, was localized by immunofluorescence in atypical mast cells of the lamina propria and in intraepithelial cells of the rat small intestine. Some mucus-secreting goblet cells also contained the protease antigen. Atypical mast cells containing the enzyme were present in large numbers beneath the epithelium of bronchioles. All atypical mast cells also contained low levels of the chymotrypsin-like protease of normal mast cells. Both enzymes were consistently present in normal connective tissue mast cells. Amino acid content, molecular weight, and lack of immunologic crossreactivity indicate that the two enzymes are similar but not identical. The cell-specific localization of the intestinal serine protease makes it unlikely that the enzyme has any general role in the degradation of pyridoxal phosphate-dependent enzymes. The function of the enzyme in mast cells, atypical mast cells, and intestinal goblet cells is not known.
一种细胞内丝氨酸蛋白酶被认为可启动几种细胞内磷酸吡哆醛依赖性酶的降解，通过免疫荧光法将其定位在固有层的非典型肥大细胞和大鼠小肠的上皮内细胞中。一些分泌黏液的杯状细胞也含有该蛋白酶抗原。含有这种酶的非典型肥大细胞大量存在于细支气管上皮下方。所有非典型肥大细胞还含有低水平的正常肥大细胞的类胰凝乳蛋白酶。这两种酶在正常结缔组织肥大细胞中始终存在。氨基酸含量、分子量以及缺乏免疫交叉反应表明这两种酶相似但不相同。肠道丝氨酸蛋白酶的细胞特异性定位表明该酶不太可能在磷酸吡哆醛依赖性酶的降解中起任何普遍作用。该酶在肥大细胞、非典型肥大细胞和肠道杯状细胞中的功能尚不清楚。
