Danielsen E M
Department of Biochemistry C, Panum Institute, University of Copenhagen, Denmark.
Biochem J. 1988 Aug 15;254(1):219-22. doi: 10.1042/bj2540219.
The effect of 2,6-dichloro-4-nitrophenol (DCNP), an inhibitor of phenol sulphotransferases (EC 2.8.2.-), on the biosynthesis of aminopeptidase N (EC 3.4.11.2) was studied in organ-cultured pig intestinal mucosal explants. At 50 microM DCNP did not affect protein synthesis but it decreased incorporation of [35S]sulphate into aminopeptidase N and other major microvillar hydrolases by 70-85% compared with controls, indicating an inhibition of their post-translational tyrosine sulphation. In labelling experiments with [35S]methionine from 0.5 to 5 h, DCNP was tested for its possible influence on synthesis, processing and microvillar expression of aminopeptidase N, but no effect on any of these parameters could be detected. It can therefore be concluded that tyrosine sulphation is not required (for instance as a sorting signal) for the targeting of newly synthesized enzymes to the microvillar membrane.
在器官培养的猪肠黏膜外植体中，研究了酚磺基转移酶（EC 2.8.2.-）的抑制剂2,6 - 二氯 - 4 - 硝基苯酚（DCNP）对氨肽酶N（EC 3.4.11.2）生物合成的影响。在50微摩尔浓度下，DCNP不影响蛋白质合成，但与对照组相比，它使[35S]硫酸盐掺入氨肽酶N和其他主要微绒毛水解酶的量减少了70 - 85%，表明其对这些酶的翻译后酪氨酸硫酸化有抑制作用。在用[35S]甲硫氨酸进行0.5至5小时的标记实验中，测试了DCNP对氨肽酶N的合成、加工和微绒毛表达的可能影响，但未检测到对这些参数有任何影响。因此可以得出结论，新合成的酶靶向微绒毛膜不需要酪氨酸硫酸化（例如作为分选信号）。
