RecA family recombinases play essential roles in maintaining genome integrity. A group of RecA-like proteins named RadC are present in all archaea, but their in vivo functions remain unclear. In this study, we perform...RecA family recombinases play essential roles in maintaining genome integrity. A group of RecA-like proteins named RadC are present in all archaea, but their in vivo functions remain unclear. In this study, we performed phylogenetic and genetic analysis of two RadC proteins from Sulfolobus islandicus. RadC is closer to the KaiC lineage of cyanobacteria and proteobacteria than to the lineage of the recombinases （RecA, RadA, and Rad51） and the recombinase paralogs （e.g., RadB, Rad55, and Rad51B）. Using the recently- established S. islandicus genetic system, we constructed deletion and over-expression strains of radC1 and radC2. Deletion of radC1 rendered the cells more sensitive to DNA damaging agents, methyl methanesulfonate （MMS）, hydroxyurea （HU）, and ultraviolet （UV） radiation, than the wild type, and a AradCIAradC2 double deletion strain was more sensitive to cisplatin and MMS than the AradC1 single deletion mutant. In addition, ectopic expression of His-tagged RadC 1 revealed that RadC I was co-purified with a putative structure-specific nuclease and ATPase, which is highly conserved in archaea. Our results indicate that both RadCI and RadC2 are involved in DNA repair. RadCl may play a general or primary role in DNA repair, while RadC2 plays a role in DNA repair in response to specific DNA damages.展开更多
Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting ...Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting swarming migration in collectivity. On the contrary, recently it has been described that RecA promotes cellular apoptotic-like death (ALD), a pathway of programmed cellular death (PCD). In fact, RecA has been dubbed as the major apoptotic executor in E. coli. From these studies, RecA emerges as a prototypical Gin/Gan protein that despite of their intrinsic vital and lethal anfi-funcionality becomes in a WISE factor: a Worker to Integrate Survival and Evolution in E. coli evolving populations living in community. Here, I provide a review of recent experimental and conceptual advances trying to understand these RecA’s antagonistic roles in appearance contradictory under a unified biological vision.展开更多
基金supported by the grants from the National Natural Science Foundation of China(Nos.3093002 and 31170072) to Y.SDanish Council of Independent Research(No.FTP/11-106683) to Q.S
文摘RecA family recombinases play essential roles in maintaining genome integrity. A group of RecA-like proteins named RadC are present in all archaea, but their in vivo functions remain unclear. In this study, we performed phylogenetic and genetic analysis of two RadC proteins from Sulfolobus islandicus. RadC is closer to the KaiC lineage of cyanobacteria and proteobacteria than to the lineage of the recombinases （RecA, RadA, and Rad51） and the recombinase paralogs （e.g., RadB, Rad55, and Rad51B）. Using the recently- established S. islandicus genetic system, we constructed deletion and over-expression strains of radC1 and radC2. Deletion of radC1 rendered the cells more sensitive to DNA damaging agents, methyl methanesulfonate （MMS）, hydroxyurea （HU）, and ultraviolet （UV） radiation, than the wild type, and a AradCIAradC2 double deletion strain was more sensitive to cisplatin and MMS than the AradC1 single deletion mutant. In addition, ectopic expression of His-tagged RadC 1 revealed that RadC I was co-purified with a putative structure-specific nuclease and ATPase, which is highly conserved in archaea. Our results indicate that both RadCI and RadC2 are involved in DNA repair. RadCl may play a general or primary role in DNA repair, while RadC2 plays a role in DNA repair in response to specific DNA damages.
文摘Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting swarming migration in collectivity. On the contrary, recently it has been described that RecA promotes cellular apoptotic-like death (ALD), a pathway of programmed cellular death (PCD). In fact, RecA has been dubbed as the major apoptotic executor in E. coli. From these studies, RecA emerges as a prototypical Gin/Gan protein that despite of their intrinsic vital and lethal anfi-funcionality becomes in a WISE factor: a Worker to Integrate Survival and Evolution in E. coli evolving populations living in community. Here, I provide a review of recent experimental and conceptual advances trying to understand these RecA’s antagonistic roles in appearance contradictory under a unified biological vision.
