Fanti L, Giovinazzo G, Berloco M, Pimpinelli S
Istituto di Genetica, Università di Bari, Italy.
Mol Cell. 1998 Nov;2(5):527-38. doi: 10.1016/s1097-2765(00)80152-5.
HP1 (Heterochromatin protein 1) is a conserved, non-histone chromosomal protein that is best known for its preferential binding to pericentric heterochromatin and its role in position effect variegation in Drosophila. Using immunolocalization, we show that HP1 is a constant feature of the telomeres of interphase polytene and mitotic chromosomes. This localization does not require the presence of telomeric retrotransposons, since HP1 is also detected at the ends of terminally deleted chromosomes that lack these elements. Importantly, larvae expressing reduced or mutant versions of HP1 exhibit aberrant chromosome associations and multiple telomeric fusions in neuroblast cells, imaginal disks, and male meiotic cells. Taken together, these results provide evidence that HP1 plays a functional role in mediating normal telomere behavior in Drosophila.
异染色质蛋白1（HP1）是一种保守的非组蛋白染色体蛋白，因其优先结合着丝粒周围异染色质以及在果蝇位置效应斑驳中所起的作用而广为人知。通过免疫定位，我们发现HP1是间期多线染色体和有丝分裂染色体端粒的一个恒定特征。这种定位并不需要端粒逆转座子的存在，因为在缺乏这些元件的末端缺失染色体的末端也能检测到HP1。重要的是，表达HP1减少或突变版本的幼虫在神经母细胞、成虫盘和雄性减数分裂细胞中表现出异常的染色体关联和多个端粒融合。综上所述，这些结果提供了证据表明HP1在介导果蝇正常端粒行为中发挥功能作用。
