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Identification of a family of group II introns encoding LAGLIDADG ORFs typical of group I introns.

ABSTRACT: Group I and group II introns are unrelated classes of introns that each encode proteins that facilitate intron splicing and intron mobility. Here we describe a new subfamily of nine introns in fungi that are group II introns but encode LAGLIDADG ORFs typical of group I introns. The introns have fairly standard group IIB1 RNA structures and are inserted into three different sites in SSU and LSU rRNA genes. Therefore, introns should not be assumed to be group I introns based solely on the presence of a LAGLIDADG ORF.

SUBMITTER: Toor N

PROVIDER: S-EPMC1370344 | biostudies-other | 2002 Nov

REPOSITORIES: biostudies-other

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Identification of a family of group II introns encoding LAGLIDADG ORFs typical of group I introns.

Toor Navtej N Zimmerly Steven S

RNA (New York, N.Y.) 20021101 11

Group I and group II introns are unrelated classes of introns that each encode proteins that facilitate intron splicing and intron mobility. Here we describe a new subfamily of nine introns in fungi that are group II introns but encode LAGLIDADG ORFs typical of group I introns. The introns have fairly standard group IIB1 RNA structures and are inserted into three different sites in SSU and LSU rRNA genes. Therefore, introns should not be assumed to be group I introns based solely on the presence ...[more]

PMID: 12458791

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