Transcription in archaea: similarity to that in eucarya.
AUTOR(ES)
Langer, D
RESUMO
We present homologies between archaeal and eucaryal DNA-dependent RNA polymerase (RNAP) subunits and transcription factors. The sequences of the Sulfolobus acidocaldarius subunits D, E, and N and alignments with eucaryal homologs are presented here. The similarities between archaeal transcription factors and their eucaryal homologs TFIIB and TBP have been established in other laboratories. The archaeal RNAP subunits H, K, and N, respectively, show high sequence similarity to ABC27, ABC23, and ABC10 beta (found in all three eucaryal RNAPs); subunit D, to AC40 (common to polymerase II and polymerase III) and B44 (polymerase II); and subunit L, to AC19 and B12.5. The similarity of subunit D and its eucaryal homologs to bacterial alpha is limited to the "alpha-motif," which is also present in subunit L and its eucaryal homologs. Genes encoding homologs of the related eucaryal RNAP subunits A12.2/B12.6 and also homologs of eucaryal transcription elongation factors of the TFIIS family have been detected in Sulfolobus acidocaldarius and Thermococcus celer. In archaea, the protein is not an RNAP subunit. Together with the sequence similarities between archaeal box A-containing and eucaryal TATA box-containing promoters, this shows that the archaeal and eucaryal transcription systems are truly homologous and that they differ structurally and functionally from the bacterial transcription machinery. In contrast, however, a number of genes for the archaeal transcription apparatus are organized in clusters resembling the clusters of transcription-associated genes in Bacteria.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=41582Documentos Relacionados
- Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya.
- Color sensing in the Archaea: a eukaryotic-like receptor coupled to a prokaryotic transducer.
- Archaea: narrowing the gap between prokaryotes and eukaryotes.
- Size Comparisons among Integral Membrane Transport Protein Homologues in Bacteria, Archaea, and Eucarya
- Transcription factor IID in the Archaea: sequences in the Thermococcus celer genome would encode a product closely related to the TATA-binding protein of eukaryotes.