Hamvas R M, Reik W, Gaunt S J, Brown S D, Singh P B
Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, London, UK.
Mamm Genome. 1992;2(1):72-5. doi: 10.1007/BF00570443.
Modifiers of position-effect-variegation in Drosophila are thought to encode proteins that are either structural components of heterochromatin or enzymes that modify these components. We have recently shown that a sequence motif found in one Drosophila modifier gene, Heterochromatin protein 1 (HP1), is conserved in a wide variety of animal and plant species (Singh et al. 1991). Using this motif, termed chromo box, we have cloned a mouse candidate modifier gene, M31, that also shows considerable sequence homology to Drosophila HP1. Here we report evidence of at least four independently segregating loci in the mouse homologous to the M31 cDNA. One of these loci--Cbx-rs1--maps to the X Chromosome (Chr), 1 cM proximal to Amg and outside the X-inactivation center region.
果蝇中位置效应斑驳的修饰因子被认为编码的蛋白质要么是异染色质的结构成分，要么是修饰这些成分的酶。我们最近发现，在一个果蝇修饰基因异染色质蛋白1（HP1）中发现的一个序列基序，在多种动植物物种中都保守存在（辛格等人，1991年）。利用这个被称为染色体框的基序，我们克隆了一个小鼠候选修饰基因M31，它与果蝇HP1也有相当程度的序列同源性。在此我们报告，在小鼠中至少有四个与M31 cDNA同源的独立分离位点的证据。其中一个位点——Cbx-rs1——定位于X染色体（Chr），在Amg近端1厘摩处，且在X染色体失活中心区域之外。
