Excellent post.
There are more examples of recent activity in ERVs with phylogenetic implications for example polymorphic HERVs in humans
quote:
Turner G, Barbulescu M, Su M, Jensen-Seaman MI, Kidd KK, Lenz J.
Insertional polymorphisms of full-length endogenous retroviruses in humans.Curr Biol. 2001 Oct 2;11(19):1531-5.
An interesting HERV-K (one of the more active groups i.e. the Class II HERVs) that groups chimps and gorillas more closely than chimp to human.
quote:
Barbulescu M, Turner G, Su M, Kim R, Jensen-Seaman MI, Deinard AS, Kidd KK, Lenz J. A HERV-K provirus in chimpanzees, bonobos and gorillas, but not humans.
Curr Biol. 2001 May 15;11(10):779-83.
And human unique HERVs (again HERV-K)
quote:
Barbulescu M, Turner G, Seaman MI, Deinard AS, Kidd KK, Lenz J.
Many human endogenous retrovirus K (HERV-K) proviruses are unique to humans.Curr Biol. 1999 Aug 26;9(16):861-8.
Keep your eyes peeled in Virology over the next few months...a certain EvC poster has a paper in press on the evolution of all ERV classes in anthropoid primates
Wait a bit longer and the comparative expression in different non-human primate tissues will be published as well.....
A paper on the expression of HERVs in different human tissues just came out in January.
quote:
Seifarth W, Frank O, Zeilfelder U, Spiess B, Greenwood AD, Hehlmann R, Leib-Mosch C. Comprehensive analysis of human endogenous retrovirus transcriptional activity in human tissues with a retrovirus-specific microarray.J Virol. 2005 Jan;79(1):341-52.
For functional uses of ERVs, I have often brought up syncytin..of great interest to me, an example of convergent evolution for Syncyctin has been found in mouse where an unrelated element i.e. not a HERV-W or HERV-FRD related element is responsible for placenta formation in mice, just like in humans
quote:
Dupressoir A, Marceau G, Vernochet C, Benit L, Kanellopoulos C, Sapin V, Heidmann T. Syncytin-A and syncytin-B, two fusogenic placenta-specific murine envelope genes of retroviral origin conserved in Muridae.
Proc Natl Acad Sci U S A. 2005 Jan 18;102(3):725-30. Epub 2005 Jan 11.
Finally, a very important paper just came out in Nature demonstrating one way the genome controls HERVs so that they don't retrotranspose out of control and destroy the genome.
quote:
Esnault C, Heidmann O, Delebecque F, Dewannieux M, Ribet D, Hance AJ, Heidmann T, Schwartz O. APOBEC3G cytidine deaminase inhibits retrotransposition of endogenous retroviruses.
Nature. 2005 Jan 27;433(7024):430-3.
Junk DNA seems to be pretty busy these days...with lots of nice data supporting evolution...tough luck for Charlton Heston and the rest of the creationists