Stalled Xenopus RNA polymerase I (pol I) elongation complexes bearing a 52-nucleotide RNA were prepared by promoter-initiated transcription in the absence of UTP. When such complexes were isolated and incubated in the presence of Mg2+, the associated RNA was shortened from the 3'-end, and mono- and dinucleotides were released. Shortened transcripts were still associated with the DNA and were quantitatively reelongated upon addition of NTPs. The cleavage activity could be removed from the pol I-ternary complex with buffers containing 0.25% Sarkosyl. These findings indicate that a factor with characteristics similar to elongation factor TFIIS is associated with the pol I elongation complex. However, addition of recombinant Xenopus TFIIS to Sarkosyl-washed pol I elongation complexes had no effect, whereas it showed the expected effects in control reactions with identically prepared pol II elongation complexes. The results thus suggest the existence of a pol I-specific cleavage/elongation factor. I also report the sequence of a novel type of Xenopus TFIIS. The predicted amino acid sequences of the present and previously identified Xenopus TFIIS are less than 65% conserved. Thus, like mammalian species, Xenopus has at least two highly divergent forms of TFIIS.
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http://purl.uniprot.org/cit... | rdf:type | uniprot:Journal_Citation | lld:uniprot |
http://purl.uniprot.org/cit... | rdfs:comment | Stalled Xenopus RNA polymerase I (pol I) elongation complexes bearing a 52-nucleotide RNA were prepared by promoter-initiated transcription in the absence of UTP. When such complexes were isolated and incubated in the presence of Mg2+, the associated RNA was shortened from the 3'-end, and mono- and dinucleotides were released. Shortened transcripts were still associated with the DNA and were quantitatively reelongated upon addition of NTPs. The cleavage activity could be removed from the pol I-ternary complex with buffers containing 0.25% Sarkosyl. These findings indicate that a factor with characteristics similar to elongation factor TFIIS is associated with the pol I elongation complex. However, addition of recombinant Xenopus TFIIS to Sarkosyl-washed pol I elongation complexes had no effect, whereas it showed the expected effects in control reactions with identically prepared pol II elongation complexes. The results thus suggest the existence of a pol I-specific cleavage/elongation factor. I also report the sequence of a novel type of Xenopus TFIIS. The predicted amino acid sequences of the present and previously identified Xenopus TFIIS are less than 65% conserved. Thus, like mammalian species, Xenopus has at least two highly divergent forms of TFIIS. | lld:uniprot |
http://purl.uniprot.org/cit... | skos:exactMatch | http://purl.uniprot.org/pub... | lld:uniprot |
http://purl.uniprot.org/cit... | skos:exactMatch | http://purl.uniprot.org/med... | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:name | J. Biol. Chem. | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:author | Labhart P. | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:date | 1997 | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:pages | 9055-9061 | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:title | Transcript cleavage in an RNA polymerase I elongation complex. Evidence for a dissociable activity similar to but distinct from TFIIS. | lld:uniprot |
http://purl.uniprot.org/cit... | uniprot:volume | 272 | lld:uniprot |
uniprot-protein:Q91692 | uniprot:citation | http://purl.uniprot.org/cit... | lld:uniprot |
http://linkedlifedata.com/r... | uniprot:citation | http://purl.uniprot.org/cit... | lld:uniprot |
http://linkedlifedata.com/r... | rdf:object | http://purl.uniprot.org/cit... | lld:uniprot |