Gutowski J K, Cohen S
Cell Immunol. 1983 Feb 1;75(2):300-11. doi: 10.1016/0008-8749(83)90328-3.
Cytoplasmic extracts, prepared from continuously proliferating lymphoblastoid cells, as well as mitogen-activated normal lymphocytes, contain an extractable factor capable of inducing DNA synthesis in isolated quiescent nuclei. This factor is not detectable in resting cells. It is nondialyzable, precipitable by 30-50% saturated ammonium sulfate, and inactivated by trypsin. It is heat sensitive, but stable to cold and lyophilization. The molecular weight of the factor is greater than 100,000. This cytoplasmic activator of nuclear DNA replication is not released from the cell, and has no effect on intact cells. This suggests that it serves as an intracellular mitogenic signal in replicating cells.
从持续增殖的淋巴母细胞以及有丝分裂原激活的正常淋巴细胞制备的细胞质提取物，含有一种可提取因子，该因子能够诱导分离的静止细胞核中的DNA合成。在静止细胞中无法检测到这种因子。它不能透析，可被30 - 50%饱和度的硫酸铵沉淀，并且可被胰蛋白酶灭活。它对热敏感，但对冷和冻干稳定。该因子的分子量大于100,000。这种核DNA复制的细胞质激活剂不会从细胞中释放出来，并且对完整细胞没有作用。这表明它在复制细胞中作为一种细胞内有丝分裂信号起作用。
