Feng Wang, Qing He, Nina Y. Yao, Michael E. O’Donnell, Huilin Li
{"title":"人类 ATAD5 已进化出独特的结构元素,专门作为 PCNA 卸载器发挥作用","authors":"Feng Wang, Qing He, Nina Y. Yao, Michael E. O’Donnell, Huilin Li","doi":"10.1038/s41594-024-01332-4","DOIUrl":null,"url":null,"abstract":"<p>Humans have three different proliferating cell nuclear antigen (PCNA) clamp-loading complexes: RFC and CTF18-RFC load PCNA onto DNA, but ATAD5-RFC can only unload PCNA from DNA. The underlying structural basis of ATAD5-RFC unloading is unknown. We show here that ATAD5 has two unique locking loops that appear to tie the complex into a rigid structure, and together with a domain that plugs the DNA-binding chamber, prevent conformation changes required for DNA binding, likely explaining why ATAD5-RFC is exclusively a PCNA unloader. These features are conserved in the yeast PCNA unloader Elg1-RFC. We observe intermediates in which PCNA bound to ATAD5-RFC exists as a closed planar ring, a cracked spiral or a gapped spiral. Surprisingly, ATAD5-RFC can open a PCNA gap between PCNA protomers 2 and 3, different from the PCNA protomers 1 and 3 gap observed in all previously characterized clamp loaders.</p>","PeriodicalId":18822,"journal":{"name":"Nature structural & molecular biology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The human ATAD5 has evolved unique structural elements to function exclusively as a PCNA unloader\",\"authors\":\"Feng Wang, Qing He, Nina Y. Yao, Michael E. O’Donnell, Huilin Li\",\"doi\":\"10.1038/s41594-024-01332-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Humans have three different proliferating cell nuclear antigen (PCNA) clamp-loading complexes: RFC and CTF18-RFC load PCNA onto DNA, but ATAD5-RFC can only unload PCNA from DNA. The underlying structural basis of ATAD5-RFC unloading is unknown. We show here that ATAD5 has two unique locking loops that appear to tie the complex into a rigid structure, and together with a domain that plugs the DNA-binding chamber, prevent conformation changes required for DNA binding, likely explaining why ATAD5-RFC is exclusively a PCNA unloader. These features are conserved in the yeast PCNA unloader Elg1-RFC. We observe intermediates in which PCNA bound to ATAD5-RFC exists as a closed planar ring, a cracked spiral or a gapped spiral. Surprisingly, ATAD5-RFC can open a PCNA gap between PCNA protomers 2 and 3, different from the PCNA protomers 1 and 3 gap observed in all previously characterized clamp loaders.</p>\",\"PeriodicalId\":18822,\"journal\":{\"name\":\"Nature structural & molecular biology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-06-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Nature structural & molecular biology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1038/s41594-024-01332-4\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nature structural & molecular biology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1038/s41594-024-01332-4","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
The human ATAD5 has evolved unique structural elements to function exclusively as a PCNA unloader
Humans have three different proliferating cell nuclear antigen (PCNA) clamp-loading complexes: RFC and CTF18-RFC load PCNA onto DNA, but ATAD5-RFC can only unload PCNA from DNA. The underlying structural basis of ATAD5-RFC unloading is unknown. We show here that ATAD5 has two unique locking loops that appear to tie the complex into a rigid structure, and together with a domain that plugs the DNA-binding chamber, prevent conformation changes required for DNA binding, likely explaining why ATAD5-RFC is exclusively a PCNA unloader. These features are conserved in the yeast PCNA unloader Elg1-RFC. We observe intermediates in which PCNA bound to ATAD5-RFC exists as a closed planar ring, a cracked spiral or a gapped spiral. Surprisingly, ATAD5-RFC can open a PCNA gap between PCNA protomers 2 and 3, different from the PCNA protomers 1 and 3 gap observed in all previously characterized clamp loaders.