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U12 intron positions are more strongly conserved between animals and plants than U2 intron positions.

ABSTRACT: We report that the positions of minor, U12 introns are conserved in orthologous genes from human and Arabidopsis to an even greater extent than the positions of the major, U2 introns. The U12 introns, especially, conserved ones are concentrated in 5'-portions of plant and animal genes, where the U12 to U2 conversions occurs preferentially in the 3'-portions of genes. These results are compatible with the hypothesis that the high level of conservation of U12 intron positions and their persistence in genomes despite the unidirectional U12 to U2 conversion are explained by the role of the slowly excised U12 introns in down-regulation of gene expression.

SUBMITTER: Basu MK

PROVIDER: S-EPMC2426677 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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U12 intron positions are more strongly conserved between animals and plants than U2 intron positions.

Basu Malay Kumar MK Makalowski Wojciech W Rogozin Igor B IB Koonin Eugene V EV

Biology direct 20080514

We report that the positions of minor, U12 introns are conserved in orthologous genes from human and Arabidopsis to an even greater extent than the positions of the major, U2 introns. The U12 introns, especially, conserved ones are concentrated in 5'-portions of plant and animal genes, where the U12 to U2 conversions occurs preferentially in the 3'-portions of genes. These results are compatible with the hypothesis that the high level of conservation of U12 intron positions and their persistence ...[more]

PMID: 18479526

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