title: Potential multiple endonuclease functions and a ribonuclease H encoded in retroposon genomes.
abstract: Among the retroposons, the source of the endonuclease activity is known to be variable and can be provided as either a retroviral-like integrase or a protein similar to the cellular apurinic-apyrimidinic endonuclease. It has also been reported that other retroposon and retrointron sequences have limited similarity to various eubacterial endonucleases. We investigated whether any retroposon genomes possibly encode multiple endonuclease functions. Amino acid alignments were generated and analyzed for the presence of the characterized ordered-series-of-motifs (OSM) representative of four different endonuclease functions. The results indicate that SLACS, CZAR, CRE1, CRE2, and some Trypanosoma brucei retroposon sequences encode multiple putative endonuclease functions. Interestingly, one of the endonuclease functions is embedded within the potential ribonuclease H sequence found in SLACS, CZAR, CRE1, CRE2, and R2BM retroposons.
authors.affiliation: Department of Microbiology, Montana State University, Bozeman, Montana 59717, USA. mars@parvati.msu.montana.edu
authors.forename: Marcella A
authors.initials: MA
authors.lastname: McClure
authors.forename: Eric
authors.initials: E
authors.lastname: Donaldson
authors.forename: Seanna
authors.initials: S
authors.lastname: Corro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019757:Carbon-Oxygen Lyases / Q000235:genetics; D003001:Cloning, Molecular; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D004268:DNA-Binding Proteins / Q000235:genetics; D004720:Endonucleases / Q000235:genetics / Q000502:physiology*; D005656:Fungal Proteins; D016680:Genome, Bacterial; D015894:Genome, Human; D018745:Genome, Plant; D018503:Genome, Protozoan; D016679:Genome, Viral; D006801:Humans; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics; D015221:Potassium Channels / Q000235:genetics; D000081033:Potassium Channels, Sodium-Activated; D012097:Repressor Proteins / Q000235:genetics; D018626:Retroelements / Q000502:physiology*; D016914:Ribonuclease H / Q000235:genetics / Q000502:physiology*; D016335:Zinc Fingers / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009419:Nerve Tissue Proteins; D015221:Potassium Channels; D000081033:Potassium Channels, Sodium-Activated; D012097:Repressor Proteins; D018626:Retroelements; C000626167:kcnt1 protein, rat; D004720:Endonucleases; D016914:Ribonuclease H; D019757:Carbon-Oxygen Lyases; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase