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Parallel relaxation of stringent RNA recognition in plant and mammalian L1 retrotransposons.

ABSTRACT: L1 elements are mammalian non-long terminal repeat retrotransposons, or long interspersed elements (LINEs), that significantly influence the dynamics and fluidity of the genome. A series of observations suggest that plant L1-clade LINEs, just as mammalian L1s, mobilize both short interspersed elements (SINEs) and certain messenger RNA by recognizing the 3'-poly(A) tail of RNA. However, one L1 lineage in monocots was shown to possess a conserved 3'-end sequence with a solid RNA structure also observed in maize and sorghum SINEs. This strongly suggests that plant LINEs require a particular 3'-end sequence during initiation of reverse transcription. As one L1-clade LINE was also found to share the 3'-end sequence with a SINE in a green algal genome, I propose that the ancestral L1-clade LINE in the common ancestor of green plants may have recognized the specific RNA template, with stringent recognition then becoming relaxed during the course of plant evolution.

SUBMITTER: Ohshima K

PROVIDER: S-EPMC3472496 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Parallel relaxation of stringent RNA recognition in plant and mammalian L1 retrotransposons.

Ohshima Kazuhiko K

Molecular biology and evolution 20120605 11

L1 elements are mammalian non-long terminal repeat retrotransposons, or long interspersed elements (LINEs), that significantly influence the dynamics and fluidity of the genome. A series of observations suggest that plant L1-clade LINEs, just as mammalian L1s, mobilize both short interspersed elements (SINEs) and certain messenger RNA by recognizing the 3'-poly(A) tail of RNA. However, one L1 lineage in monocots was shown to possess a conserved 3'-end sequence with a solid RNA structure also obs ...[more]

PMID: 22675029

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