Humphreys-Beher M G, Schneyer C A
Department of Microbiology, University of Alabama, Birmingham 35294.
Biochem J. 1987 Sep 1;246(2):387-91. doi: 10.1042/bj2460387.
Maintenance of rats for 2 weeks on a diet consisting of 50% inert cellulose and 50% laboratory chow resulted in hypertrophy of the parotid gland and a 4-fold increase in total membrane-associated 4 beta-galactosyltransferase enzyme activity (EC 2.4.1.38). Localization of the increased specific activity to the cell surface of the enlarged gland was shown by subcellular fractionation of Golgi and plasma membranes. This observation was confirmed by enzyme assays of intact cells; quantification of immunofluorescence was made by using a fluorescence activated cell sorter. Parotid gland hypertrophy was inhibited by the administration of the specific modifier protein alpha-lactalbumin as well as by a monospecific antibody for 4 beta-galactosyltransferase. These agents also inhibited the incorporation of thymidine into DNA.
将大鼠置于由50%惰性纤维素和50%实验室饲料组成的饮食中饲养2周，导致腮腺肥大，且与膜相关的总4-β-半乳糖基转移酶活性（EC 2.4.1.38）增加了4倍。通过高尔基体膜和质膜的亚细胞分级分离表明，增加的比活性定位于增大腺体的细胞表面。完整细胞的酶分析证实了这一观察结果；使用荧光激活细胞分选仪对免疫荧光进行定量。腮腺肥大受到特异性修饰蛋白α-乳白蛋白以及4-β-半乳糖基转移酶单特异性抗体的抑制。这些试剂也抑制了胸腺嘧啶核苷掺入DNA。
