RESEARCH COMMONS
LIBRARY

Transposon Exaptation In Mammalian Evolution

ResearchCommons/Manakin Repository

Transposon Exaptation In Mammalian Evolution

Show full item record

Title: Transposon Exaptation In Mammalian Evolution
Author: Hucks, Donald
Abstract: A growing body of work suggests that the exaptation of transposon-derived sequences to perform beneficial cellular functions has played a significant role in eukaryotic evolution. In chapter 1, we present an analysis of 10 exapted pogo transposons in the human genome. We present evidence that all 10 are restricted to tetrapods, and that 8 of the 10 arose early in mammalian evolution, in several independent exaptation events involving diverse pogo lineages. We show that all 10 have been subject to stringent selection throughout mammalian evolution, with pseudogenization having occurred only infrequently. In 4 of these genes, we observed no cases of gene loss, consistent with a very high selective value for these genes. We also present evidence that all 10 genes encode sequence-specific DNA-binding proteins, each likely to bind a highly constrained, but as yet unknown, sequence somewhere within the mammalian genome. In chapter 2, we present evidence that a motif occurring within the terminal inverted repeats (TIRs) of Hsmar1 and made1 transposons is subject to purifying selection at a number of loci in anthropoid genomes as binding sites for SETMAR, the protein product of an anthropoid-specific gene formed some 50 mya by fusion of an Hsmar1 transposon with an extant histone methyltransferase gene. Together, our analyses support the notion that this complementary nature of transposon exaptation, the host recruitment of transposase as DNA-binding protein and non-coding transposon sequence as binding site, has been a recurrent theme in mammalian evolution.
URI: http://hdl.handle.net/10106/977
Date: 2008-08-08
External Link: https://www.uta.edu/ra/real/editprofile.php?onlyview=1&pid=15

Files in this item

Files Size Format View
umi-uta-2073.pdf 595.0Kb PDF View/Open
595.0Kb PDF View/Open

This item appears in the following Collection(s)

Show full item record

Browse

My Account

Statistics

About Us