Evolutionary connection between the catalytic subunits of DNA-dependent RNA polymerases and eukaryotic RNA-dependent RNA polymerases and the origin of RNA polymerases.
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ABSTRACT:
SUBMITTER: Iyer LM
PROVIDER: S-EPMC151600 | biostudies-literature | 2003 Jan
REPOSITORIES: biostudies-literature
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Evolutionary connection between the catalytic subunits of DNA-dependent RNA polymerases and eukaryotic RNA-dependent RNA polymerases and the origin of RNA polymerases.
Iyer Lakshminarayan M LM Koonin Eugene V EV Aravind L L
BMC structural biology 20030128
<h4>Background</h4>The eukaryotic RNA-dependent RNA polymerase (RDRP) is involved in the amplification of regulatory microRNAs during post-transcriptional gene silencing. This enzyme is highly conserved in most eukaryotes but is missing in archaea and bacteria. No evolutionary relationship between RDRP and other polymerases has been reported so far, hence the origin of this eukaryote-specific polymerase remains a mystery.<h4>Results</h4>Using extensive sequence profile searches, we identified ba ...[more]
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