Tsukahara T, Ishiura S, Kominami E, Sugita H
National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.
Exp Cell Res. 1990 May;188(1):111-6. doi: 10.1016/0014-4827(90)90284-h.
Changes in intracellular proteinase activities were examined during DMSO-induced differentiation of murine erythroleukemia cells. Suc-APA-MCA hydrolytic activity was significantly decreased, and apparent ATP-dependent multicatalytic proteinase activity was also decreased with MEL cell differentiation. Cathepsin B and L activity was mainly present in the microsomal fraction of control cells, but a part of this activity had shifted to the lysosomal fraction of differentiated cells. With the translocation of cathepsin B from the microsomal to the lysosomal fraction, the pro-enzyme form of cathepsin B was converted into the mature enzyme. These results suggest that the lysosomal pathway contributes to the degradation of specific proteins with cell differentiation.
在二甲基亚砜诱导的小鼠红白血病细胞分化过程中，对细胞内蛋白酶活性的变化进行了检测。Suc-APA-MCA水解活性显著降低，且随着MEL细胞分化，明显的ATP依赖性多催化蛋白酶活性也降低。组织蛋白酶B和L活性主要存在于对照细胞的微粒体部分，但该活性的一部分已转移至分化细胞的溶酶体部分。随着组织蛋白酶B从微粒体部分转运至溶酶体部分，组织蛋白酶B的酶原形式转化为成熟酶。这些结果表明，溶酶体途径有助于细胞分化过程中特定蛋白质的降解。
