Showing papers by "Stephen D. Bell published in 2004"
TL;DR: This work describes the identification of two active origins of replication in the single chromosome of the hyperthermophilic archaeon Sulfolobus solfataricus and identifies conserved sequence motifs within the origins that are recognized by a family of three Sulfoobus proteins that are homologous to the eukaryotic initiator proteins Orc1 and Cdc6.
263 citations
TL;DR: It is revealed that the two-subunit DNA-dependent primase possesses a template-independent 3'-terminal nucleotidyl transferase activity, which is crucial for nucleic acid synthesis and residues important for the binding of free nucleotides.
76 citations
TL;DR: The potential for promoter melting by SSB is demonstrated, suggesting a plausible basis for the stimulation of transcription and revealing an unexpected role for single-stranded DNA-binding proteins in transcription in archaea.
Abstract: Archaeal transcription utilizes a complex multisubunit RNA polymerase and the basal transcription factors TBP and TF(II)B, closely resembling its eukaryal counterpart. We have uncovered a tight physical and functional interaction between RNA polymerase and the single-stranded DNA-binding protein SSB in Sulfolobus solfataricus. SSB stimulates transcription from promoters in vitro under TBP-limiting conditions and supports transcription in the absence of TBP. SSB also rescues transcription from repression by reconstituted chromatin. We demonstrate the potential for promoter melting by SSB, suggesting a plausible basis for the stimulation of transcription. This stimulation requires both the single-stranded DNA-binding domain and the acidic C-terminal tail of the SSB. The tail forms a stable interaction with RNA polymerase. These data reveal an unexpected role for single-stranded DNA-binding proteins in transcription in archaea.
60 citations
TL;DR: Structural details of the interaction of the ring-shaped sliding clamp and the clamp loader in the process of DNA replication are revealed.
Abstract: Among the numerous molecular machines involved in the process of DNA replication are the ring-shaped sliding clamp and the clamp loader. Intriguing structural details of their interaction are now revealed.
5 citations