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A new example of viral intein in Mimivirus.

ABSTRACT: BACKGROUND: Inteins are "protein introns" that remove themselves from their host proteins through an autocatalytic protein-splicing. After their discovery, inteins have been quickly identified in all domains of life, but only once to date in the genome of a eukaryote-infecting virus. RESULTS: Here we report the identification and bioinformatics characterization of an intein in the DNA polymerase PolB gene of amoeba infecting Mimivirus, the largest known double-stranded DNA virus, the origin of which has been proposed to predate the emergence of eukaryotes. Mimivirus intein exhibits canonical sequence motifs and clearly belongs to a subclass of archaeal inteins always found in the same location of PolB genes. On the other hand, the Mimivirus PolB is most similar to eukaryotic Poldelta sequences. CONCLUSIONS: The intriguing association of an extremophilic archaeal-type intein with a mesophilic eukaryotic-like PolB in Mimivirus is consistent with the hypothesis that DNA viruses might have been the central reservoir of inteins throughout the course of evolution.

SUBMITTER: Ogata H

PROVIDER: S-EPMC549080 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature

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A new example of viral intein in Mimivirus.

Ogata Hiroyuki H Raoult Didier D Claverie Jean-Michel JM

Virology journal 20050211

<h4>Background</h4>Inteins are "protein introns" that remove themselves from their host proteins through an autocatalytic protein-splicing. After their discovery, inteins have been quickly identified in all domains of life, but only once to date in the genome of a eukaryote-infecting virus.<h4>Results</h4>Here we report the identification and bioinformatics characterization of an intein in the DNA polymerase PolB gene of amoeba infecting Mimivirus, the largest known double-stranded DNA virus, th ...[more]

PMID: 15707490

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