Transposable element fragments in protein-coding regions and their contributions to human functional proteins.

Institute of Bioinformatics, MOE Key Laboratory of Bioinformatics, State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
Gene (Impact Factor: 2.08). 11/2007; 401(1-2):165-71. DOI: 10.1016/j.gene.2007.07.012
Source: PubMed

ABSTRACT Transposable elements (TEs) and their contributions to protein-coding regions are of particular interest. Here we searched for TE fragments in Homo sapiens at both the transcript and protein levels. We found evidence in support of TE exonization and its association with alternative splicing. Despite recent findings that long evolutionary times are required to incorporate TE into proteins, we found many functional proteins with translated TE cassettes derived from young TEs. Analyses of two Bcl-family proteins and Alu-encoded segments suggest the coding and functional potential of TE sequences.

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