Gibert Jean-Michel, Karch François
Department of Zoology and Animal Biology, University of Geneva, Switzerland.
Chromosoma. 2011 Jun;120(3):297-307. doi: 10.1007/s00412-011-0312-2. Epub 2011 Feb 19.
CRAMPED (CRM), conserved from plants to animals, was previously characterized genetically as a repressive factor involved in the formation of facultative and constitutive heterochromatin (Polycomb silencing, position effect variegation). We show that crm is dynamically regulated during replication and identify the Histone gene cluster (His-C) as a major CRM target. Surprisingly, CRM is specifically required for the expression of the Histone H1 gene, like the promoter-bound transcription factor TRF2. Consistently with this, CRM genetically interacts and co-immunoprecipitates with TRF2. However, the Polycomb phenotypes observed in crm mutants are not observed in TRF2 hypomorphic mutants, suggesting that they correspond to independent roles of CRM. CRM is thus a highly pleiotropic factor involved in both activation and repression.
CRAMPED（CRM）从植物到动物都保守存在，以前在遗传学上被表征为一种参与兼性和组成型异染色质形成（多梳抑制、位置效应斑驳）的抑制因子。我们发现crm在复制过程中受到动态调控，并确定组蛋白基因簇（His-C）是CRM的主要靶点。令人惊讶的是，与启动子结合的转录因子TRF2一样，Histone H1基因的表达特别需要CRM。与此一致的是，CRM与TRF2发生遗传相互作用并进行共免疫沉淀。然而，在crm突变体中观察到的多梳表型在TRF2亚效突变体中未观察到，这表明它们对应于CRM的独立作用。因此，CRM是一种涉及激活和抑制的高度多效性因子。
