Ho-Chen Lin, Mary M Golic, Hunter J Hill, Katherine F Lemons, Truc T Vuong, Madison Smith, Forrest T Golic, Kent G Golic
{"title":"果蝇环状染色体与姐妹染色单体和同源染色体相互作用,在有丝分裂过程中产生无丝分裂桥。","authors":"Ho-Chen Lin, Mary M Golic, Hunter J Hill, Katherine F Lemons, Truc T Vuong, Madison Smith, Forrest T Golic, Kent G Golic","doi":"10.1101/2024.08.08.607186","DOIUrl":null,"url":null,"abstract":"Ring chromosomes are known in many eukaryotic organisms, including humans. They are typically associated with a variety of maladies, including abnormal development and lethality. Underlying these phenotypes are anaphase chromatin bridges that can lead to chromosome loss, nondisjunction and breakage. By cytological examination of ring chromosomes in Drosophila melanogaster we identified five causes for anaphase bridges produced by ring chromosomes. Catenation of sister chromatids is the most common cause and these bridges frequently resolve during anaphase, presumably by the action of topoisomerase II. Sister chromatid exchange and chromosome breakage followed by sister chromatid union also produce anaphase bridges. Mitotic recombination with the homolog was rare, but was another route to generation of anaphase bridges. Most surprising, was the discovery of homolog capture, where the ring chromosome was connected to its linear homolog in anaphase. We hypothesize that this is a remnant of mitotic pairing and that the linear chromosome is connected to the ring by multiple wraps produced through the action of topoisomerase II during establishment of homolog pairing. In support, we showed that in a ring/ring homozygote the two rings are frequently catenated in mitotic metaphase, a configuration that requires breaking and rejoining of at least one chromosome.","PeriodicalId":501246,"journal":{"name":"bioRxiv - Genetics","volume":"19 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Drosophila ring chromosomes interact with sisters and homologs to produce anaphase bridges in mitosis.\",\"authors\":\"Ho-Chen Lin, Mary M Golic, Hunter J Hill, Katherine F Lemons, Truc T Vuong, Madison Smith, Forrest T Golic, Kent G Golic\",\"doi\":\"10.1101/2024.08.08.607186\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Ring chromosomes are known in many eukaryotic organisms, including humans. They are typically associated with a variety of maladies, including abnormal development and lethality. Underlying these phenotypes are anaphase chromatin bridges that can lead to chromosome loss, nondisjunction and breakage. By cytological examination of ring chromosomes in Drosophila melanogaster we identified five causes for anaphase bridges produced by ring chromosomes. Catenation of sister chromatids is the most common cause and these bridges frequently resolve during anaphase, presumably by the action of topoisomerase II. Sister chromatid exchange and chromosome breakage followed by sister chromatid union also produce anaphase bridges. Mitotic recombination with the homolog was rare, but was another route to generation of anaphase bridges. Most surprising, was the discovery of homolog capture, where the ring chromosome was connected to its linear homolog in anaphase. We hypothesize that this is a remnant of mitotic pairing and that the linear chromosome is connected to the ring by multiple wraps produced through the action of topoisomerase II during establishment of homolog pairing. In support, we showed that in a ring/ring homozygote the two rings are frequently catenated in mitotic metaphase, a configuration that requires breaking and rejoining of at least one chromosome.\",\"PeriodicalId\":501246,\"journal\":{\"name\":\"bioRxiv - Genetics\",\"volume\":\"19 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-08-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"bioRxiv - Genetics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1101/2024.08.08.607186\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"bioRxiv - Genetics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1101/2024.08.08.607186","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
包括人类在内的许多真核生物都存在环状染色体。环状染色体通常与多种疾病相关,包括发育异常和致死。这些表型的基础是可导致染色体缺失、非连接和断裂的无丝分裂染色质桥。通过对黑腹果蝇的环状染色体进行细胞学检查,我们确定了环状染色体产生无丝期桥的五种原因。姐妹染色单体的卡合是最常见的原因,这些桥经常在无丝分裂过程中消失,可能是在拓扑异构酶 II 的作用下消失的。姐妹染色单体交换和染色体断裂后姐妹染色单体结合也会产生无丝分裂桥。同源染色体的有丝分裂重组很少见,但这是产生无丝分裂桥的另一个途径。最令人惊讶的是同源物捕获的发现,即环状染色体在无丝分裂期与其线性同源物相连。我们推测,这是有丝分裂配对的残余,在同源染色体配对建立过程中,通过拓扑异构酶 II 的作用,线性染色体与环状染色体通过多重缠绕连接在一起。作为佐证,我们发现在环/环同源基因中,两个环经常在有丝分裂分裂相中结合,这种构型需要至少一条染色体的断裂和重合。
Drosophila ring chromosomes interact with sisters and homologs to produce anaphase bridges in mitosis.
Ring chromosomes are known in many eukaryotic organisms, including humans. They are typically associated with a variety of maladies, including abnormal development and lethality. Underlying these phenotypes are anaphase chromatin bridges that can lead to chromosome loss, nondisjunction and breakage. By cytological examination of ring chromosomes in Drosophila melanogaster we identified five causes for anaphase bridges produced by ring chromosomes. Catenation of sister chromatids is the most common cause and these bridges frequently resolve during anaphase, presumably by the action of topoisomerase II. Sister chromatid exchange and chromosome breakage followed by sister chromatid union also produce anaphase bridges. Mitotic recombination with the homolog was rare, but was another route to generation of anaphase bridges. Most surprising, was the discovery of homolog capture, where the ring chromosome was connected to its linear homolog in anaphase. We hypothesize that this is a remnant of mitotic pairing and that the linear chromosome is connected to the ring by multiple wraps produced through the action of topoisomerase II during establishment of homolog pairing. In support, we showed that in a ring/ring homozygote the two rings are frequently catenated in mitotic metaphase, a configuration that requires breaking and rejoining of at least one chromosome.