Imbra R J, Karin M
Mol Cell Biol. 1987 Apr;7(4):1358-63. doi: 10.1128/mcb.7.4.1358-1363.1987.
The exact physiological role of metallothionein (MT) is not clear. It has been suggested that these low-molecular-weight, highly inducible, heavy-metal-binding proteins serve in the regulation of intracellular Zn metabolism. Among the Zn-requiring systems are several enzymes involved in DNA replication and repair. Therefore, during periods of active DNA synthesis there is likely to be an increased demand for Zn, which could be met by elevated MT synthesis. For that reason, we examined whether stimulation of cellular proliferation leads to increased expression of MT. We report here that treatment of cultured mammalian cells with serum growth factors and activators of protein kinase C, all of which are known to have growth stimulatory activity, led to induction of MT mRNA. One of the required steps in the signal transduction pathways triggered by these agents, ending in MT induction, appears to be the activation of protein kinase C.
金属硫蛋白（MT）的确切生理作用尚不清楚。有人提出，这些低分子量、高度可诱导的重金属结合蛋白在细胞内锌代谢的调节中发挥作用。需要锌的系统中有几种参与DNA复制和修复的酶。因此，在活跃的DNA合成期间，对锌的需求可能会增加，这可以通过增加MT的合成来满足。出于这个原因，我们研究了细胞增殖的刺激是否会导致MT表达增加。我们在此报告，用血清生长因子和蛋白激酶C激活剂处理培养的哺乳动物细胞，所有这些都已知具有生长刺激活性，导致MT mRNA的诱导。这些试剂触发的信号转导途径中导致MT诱导的必要步骤之一似乎是蛋白激酶C的激活。
