UbcD1, a Drosophila ubiquitin-conjugating enzyme required for proper telomere behavior
UbcD1, a Drosophila ubiquitin-conjugating enzyme required for proper telomere behavior
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DOI：
10.1101/gad.11.7.863
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发表时间：
1997-04-01
影响因子：
10.5
通讯作者：
Gatti, M
中科院分区：
文献类型：
--
作者：
Cenci, G;Rawson, RB;Gatti, M
在某些生物体的正常细胞以及衰老细胞和肿瘤细胞中已经观察到染色体通过其端粒的端对端缔合。这种现象背后的分子机制目前尚不清楚。我们在这里表明，五个独立的突变等位基因在果蝇UbcD1基因导致频繁的端粒端粒附件在有丝分裂和男性减数分裂，在野生型中没有看到。这些端粒的关联涉及到D.黑腹菌染色体互补，尽管频率不同。UbcD1突变体中观察到的端粒协会的模式强烈表明，野生型幼虫脑细胞的间期染色体保持Rabl方向的细胞核内，与端粒和着丝粒分离到细胞核的两侧。UbcD1基因编码I类泛素缀合（E2）酶。这表明，在果蝇细胞分裂过程中，通常需要泛素介导的蛋白水解来确保正确的端粒行为。因此，我们认为UbcD1泛素化的目标之一是端粒相关的多肽，可能有助于维持适当的染色体方向在间期。
The end-to-end association of chromosomes through their telomeres has been observed in normal cells of certain organisms, as well as in senescent and tumor cells. The molecular mechanisms underlying this phenomenon are currently unknown. We show here that five independent mutant alleles in the Drosophila UbcD1 gene cause frequent telomere-telomere attachments during both mitosis and male meiosis that are not seen in wild type. These telomeric associations involve all the telomeres of the D. melanogaster chromosome complement, albeit with different frequencies. The pattern of telomeric associations observed in UbcD1 mutants suggests strongly that the interphase chromosomes of wild-type larval brain cells maintain a Rabl orientation within the nucleus, with the telomeres and centromeres segregated to opposite sides of the nucleus. The UbcD1 gene encodes a class I ubiquitin-conjugating (E2) enzyme. This indicates that ubiquitin-mediated proteolysis is normally needed to ensure proper telomere behavior during Drosophila cell division. We therefore suggest that at least one of the targets of UbcD1 ubiquitination is a telomere-associated polypeptide that may help maintain proper chromosomal orientation during interphase.