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Eukaryotic RNAse H shares a conserved domain with caulimovirus proteins that facilitate translation of polycistronic RNA.

ABSTRACT: RNAse H (RNH1 protein) from the trypanosomatid Crithidia fasciculata has a functionally uncharacterized N-terminal domain dispensable for the RNAse H activity. Using computer methods for database search and multiple alignment, we show that the N-terminal domains of RNH1 and its homologue encoded by a cDNA from chicken lens are related to the conserved domain in caulimovirus ORF VI product that facilitates translation of polycistronic virus RNA in plant cells. We hypothesize that the N-terminal domain of eukaryotic RNAse H performs an as yet uncharacterized regulatory function, possibly in mRNA translation or turnover.

SUBMITTER: Mushegian AR

PROVIDER: S-EPMC331909 | biostudies-other | 1994 Oct

REPOSITORIES: biostudies-other

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Eukaryotic RNAse H shares a conserved domain with caulimovirus proteins that facilitate translation of polycistronic RNA.

Mushegian A R AR Edskes H K HK Koonin E V EV

Nucleic acids research 19941001 20

RNAse H (RNH1 protein) from the trypanosomatid Crithidia fasciculata has a functionally uncharacterized N-terminal domain dispensable for the RNAse H activity. Using computer methods for database search and multiple alignment, we show that the N-terminal domains of RNH1 and its homologue encoded by a cDNA from chicken lens are related to the conserved domain in caulimovirus ORF VI product that facilitates translation of polycistronic virus RNA in plant cells. We hypothesize that the N-terminal d ...[more]

PMID: 7937142

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