Yamada O, Mizoguchi H
Department of Hematology, Tokyo Women's Medical College.
Nihon Rinsho. 1998 May;56(5):1322-7.
By using three hematopoietic cell lineages including myelomonocytic, erythroblastic and megakaryocytic differentiation, downregulation of telomerase activity was found to be a general response to the induction of differentiation. The decrease in telomerase activity occurred as early as 24h when HL-60 and K562 cells were cultured in the presence of VD3, ATRA and hemin and completely disappeared after 3 days. On the other hand MEG-01 cells showed dramatic inhibition of telomerase activity after 6 days of culture with TPA. Analysis of telomeric DNA in HL-60 cells and K562 cells demonstrated no remarkable loss of telomeric DNA with cellular differentiation while loosing telomerase activity. The repression of telomerase is one of many molecular events during the complex process of cellular differentiation, and testing of additional cell lines that are capable of differentiation will be helpful for understanding the mechanisms of telomerase control.
通过使用包括髓单核细胞、成红细胞和巨核细胞分化在内的三种造血细胞谱系，发现端粒酶活性下调是分化诱导的普遍反应。当HL-60和K562细胞在维生素D3、全反式维甲酸和氯化血红素存在的情况下培养时，端粒酶活性早在24小时就开始下降，并在3天后完全消失。另一方面，MEG-01细胞在用佛波酯培养6天后，端粒酶活性受到显著抑制。对HL-60细胞和K562细胞中的端粒DNA分析表明，随着细胞分化端粒酶活性丧失，但端粒DNA没有明显丢失。端粒酶的抑制是细胞分化复杂过程中的众多分子事件之一，测试其他能够分化的细胞系将有助于理解端粒酶控制机制。
