Characterization of a differentiation-inhibitory activity from nondifferentiating mouse myeloid leukemia cells.
Characterization of a differentiation-inhibitory activity from nondifferentiating mouse myeloid leukemia cells.
复制标题
非分化小鼠骨髓性白血病细胞的分化抑制活性的表征。
作者：
J. Okabe‐Kado;M. Hayashi;Y. Honma;M. Hozumi
多种分化诱导剂诱导小鼠髓系白血病M1细胞分化。在对分化诱导剂有抗性的变异M1细胞克隆的条件培养基中发现了抑制M1细胞诱导分化的活性（i活性），并且这种i活性与细胞对分化诱导剂的抗性密切相关。本研究表明，抗性M1细胞条件培养基中的i -活性与羧甲基sepharose CL-6B结合，并用0.27-0.4 M NaCl洗脱。Sephadex G-200中i活性的凝胶过滤谱表明，具有i活性的分子具有相当大的异质性；主要i -活性的表观分子范围为60000 ~ 80000。在层析上，用Polybuffer 96-乙酸在pH 8.8-9.0洗脱i活性。胰酶处理或75℃加热30min使i活性失活。因此，主要的i活性似乎是由于一种基本蛋白(s)。
Mouse myeloid leukemic M1 cells are induced to differentiate by various differentiation inducers. Activity for inhibition of induction of differentiation of M1 cells (I-activity) has been found in conditioned medium of variant M1 cell clones resistant to differentiation inducers, and this I-activity has been shown to be closely associated with resistance of the cells to differentiation inducers. In this work, the I-activity in the conditioned medium of the resistant M1 cells was shown to bind to Carboxymethyl-Sepharose CL-6B and to be eluted with 0.27-0.4 M NaCl. The profile of gel filtration of I-activity from Sephadex G-200 indicated considerable heterogeneity in molecules with I-activity; the apparent molecular range of the main I-activity was 60,000-80,000. On chromatofocusing, the I-activity was eluted with Polybuffer 96-acetic acid at pH 8.8-9.0. The I-activity was inactivated by treatment with trypsin or by heating at 75 degrees C for 30 min. Therefore, the main I-activity seemed to be due to a basic protein(s).