van Lohuizen M
Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
Cell Mol Life Sci. 1998 Jan;54(1):71-9. doi: 10.1007/s000180050126.
Two groups of genes, the Polycomb group (Pc-G) and trithorax group (trx-G), have been identified in Drosophila to provide a transcriptional memory mechanism. They ensure the maintenance of transcription patterns of key regulators such as the Hox genes and thereby the correct execution of developmental programmes. Recent data suggest that this memory mechanism is conserved in vertebrates and plants. Here we discuss current insights into the role of mouse Pc-G genes, with a particular focus on the best-studied Bmi1, Mel18 and M33 genes, as representative examples. Common phenotypes observed in knockout mice mutant for each of these genes indicate an important role for Pc-G genes not only in regulation of Hox gene expression and axial skeleton development but also in control of proliferation and survival of haematopoietic cell lineages. Proliferation defects are also observed in other cell lineages derived from these null-mutant mice, and provide new tools to study the impact of Pc-G deregulation on cell cycle control.
在果蝇中已鉴定出两组基因，即多梳基因家族（Pc-G）和三胸节基因家族（trx-G），它们可提供一种转录记忆机制。它们确保关键调节因子（如Hox基因）转录模式的维持，从而确保发育程序的正确执行。最近的数据表明，这种记忆机制在脊椎动物和植物中是保守的。在这里，我们讨论目前对小鼠Pc-G基因作用的见解，特别关注研究得最充分的Bmi1、Mel18和M33基因，作为代表性例子。在这些基因各自的基因敲除小鼠突变体中观察到的常见表型表明，Pc-G基因不仅在Hox基因表达调控和轴向骨骼发育中起重要作用，而且在造血细胞谱系的增殖和存活控制中也起重要作用。在源自这些基因敲除突变小鼠的其他细胞谱系中也观察到增殖缺陷，这为研究Pc-G失调对细胞周期控制的影响提供了新工具。
