Dipartimento di Genetica e Biologia Molecolare Charles Darwin Sapienza, Università di Roma, Roma 00185, Italy.
Genes Dev. 2010 Aug 1;24(15):1596-601. doi: 10.1101/gad.574810.
Drosophila telomeres are elongated by transposition of specialized retroelements rather than telomerase activity, and are assembled independently of the terminal DNA sequence. Drosophila telomeres are protected by terminin, a complex that includes the HOAP (Heterochromatin Protein 1/origin recognition complex-associated protein) and Moi (Modigliani) proteins and shares the properties of human shelterin. Here we show that Verrocchio (Ver), an oligonucleotide/oligosaccharide-binding (OB) fold-containing protein related to Rpa2/Stn1, interacts physically with HOAP and Moi, is enriched only at telomeres, and prevents telomere fusion. These results indicate that Ver is a new terminin component; we speculate that, concomitant with telomerase loss, Drosophila evolved terminin to bind chromosome ends independently of the DNA sequence.
果蝇端粒通过特殊的反转录元件的转位而不是端粒酶活性来延长，并且与末端 DNA 序列无关而被组装。果蝇端粒由端粒蛋白复合体保护，该复合体包括 HOAP（异染色质蛋白 1/起始识别复合物相关蛋白）和 Moi（莫迪利亚尼）蛋白，并且具有人类庇护蛋白的特性。在这里，我们表明，与 Rpa2/Stn1 相关的寡核苷酸/寡糖结合（OB）折叠蛋白 Verrocchio（Ver）与 HOAP 和 Moi 物理相互作用，仅在端粒处富集，并防止端粒融合。这些结果表明，Ver 是一个新的端粒蛋白复合体成分；我们推测，随着端粒酶的丧失，果蝇进化出了端粒蛋白复合体，以独立于 DNA 序列的方式结合染色体末端。
