Archaea
Max Planck Society - Press Release: "Archaea, small single-celled organisms, are particularly interesting for scientists because they are able to live under extreme environmental conditions, for instance under high salt concentrations, high pH-values, or high temperatures. Nature's masters of adaptation, they are model organisms from which researchers can draw conclusions about the first organisms on earth. "
Transcriptional response to DNA damage in the archaeon Sulfolobus solfataricus -- Salerno et al. 31 (21): 6127 -- Nucleic Acids Research: "Genomic sequencing has revealed the presence of archaeal genes homologous to components of the eucaryal nucleotide excision repair (NER) pathway, which is involved in the repair of ultraviolet (UV) light-induced DNA damage. . . The cell response to UV irradiation includes transcriptional regulation of genes encoding two DNA binding proteins involved in chromosome dynamics. Moreover, several of these genes are also strongly induced by the intercalating agent actinomycin D. Thus, response to DNA damage in S.solfataricus has features essentially conserved in all three domains of life. "
archeal/eukaryal replication fork
"Interestingly, phylogenetic data suggest that the specific attributes of the eukaryal machinery could date back to an archaeal ancestor containing a rudimentary form of chromatin structure. Since nucleosomes form only on double stranded DNA, greater symmetry of the ancestral eukaryal/archaeal replication fork could facilitate the emergence of chromatin structure. "
Transcriptional response to DNA damage in the archaeon Sulfolobus solfataricus -- Salerno et al. 31 (21): 6127 -- Nucleic Acids Research: "Genomic sequencing has revealed the presence of archaeal genes homologous to components of the eucaryal nucleotide excision repair (NER) pathway, which is involved in the repair of ultraviolet (UV) light-induced DNA damage. . . The cell response to UV irradiation includes transcriptional regulation of genes encoding two DNA binding proteins involved in chromosome dynamics. Moreover, several of these genes are also strongly induced by the intercalating agent actinomycin D. Thus, response to DNA damage in S.solfataricus has features essentially conserved in all three domains of life. "
archeal/eukaryal replication fork
"Interestingly, phylogenetic data suggest that the specific attributes of the eukaryal machinery could date back to an archaeal ancestor containing a rudimentary form of chromatin structure. Since nucleosomes form only on double stranded DNA, greater symmetry of the ancestral eukaryal/archaeal replication fork could facilitate the emergence of chromatin structure. "