The Contribution of Transposable Elements to Human Proteins

Jean‐Nicolas Volff, Institut de Génomique Fonctionnelle de Lyon, Lyon, France

Published online: March 2008

DOI: 10.1002/9780470015902.a0020793

The human genome contains hundreds of genes with protein-coding exons and even complete open reading frames derived from transposable elements. These genes are involved in major biological processes such as immunity, replication, reproduction, cell proliferation and apoptosis. This demonstrates the importance of transposable elements as a genomic pool of coding sequences for the creation and evolution of gene functions.

Keywords: transposable elements; human genome; molecular domestication; exonization; evolution

Figure 1. Possible events towards the exaptation of a transposable element-derived exon. Some of these events might not be required. For example, mutational activation of cryptic splice sites is not required if functional sites are already present in the transposable element sequence, mutational shaping of the open reading frame might not be necessary and alternative splice variants with exonized transposable element will not always supplant the ancestral splice form and become constitutive.
Figure 2. Schematic representation of transposable element genes exapted during the evolution of the human lineage. ORF, open reading frame; EN, endonuclease; RT, reverse transcriptase; PR, protease; RH, ribonuclease H; IN, integrase; ENV, envelope and LTR, long terminal repeat.
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    Volff JN (2006) Turning junk into gold: domestication of transposable elements and the creation of new genes in eukaryotes. BioEssays 28: 913–922.

Related Sub-Topics:

Evolutionary Genomics | Molecular Evolution | Evolutionary Processes | Protein Evolution
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Article Title: The Contribution of Transposable Elements to Human Proteins
 
How to Cite close
Volff, Jean‐Nicolas(Mar 2008) The Contribution of Transposable Elements to Human Proteins. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0020793]