Tuliptree DNA

Forums discussing individual tree species, tree families across their range, and tree identification questions & guides.

Moderators: edfrank, dbhguru

Post Reply
User avatar
edfrank
Posts: 4217
Joined: Sun Mar 07, 2010 5:46 pm

Tuliptree DNA

Post by edfrank » Mon Apr 15, 2013 9:55 am

Public release date: 14-Apr-2013
http://www.eurekalert.org/pub_releases/ ... 041213.php

Contact: Hilary Glover
hilary.glover@biomedcentral.com
44-020-319-22370
BioMed Central
The tulip tree reveals mitochondrial genome of ancestral flowering plant

55218_web.jpg
55218_web.jpg (21.74 KiB) Viewed 575 times
Caption: The extraordinary level of conservation of the tulip tree (Liriodendron tulipifera) mitochondrial genome has redefined our interpretation of evolution of the angiosperms (flowering plants), finds research in biomed Central's open access journal BMC Biology.
Credit: Gary Coté
Usage Restrictions: None
Related news release: The tulip tree reveals mitochondrial genome of ancestral flowering plant

The extraordinary level of conservation of the tulip tree (Liriodendron tulipifera) mitochondrial genome has redefined our interpretation of evolution of the angiosperms (flowering plants), finds research in biomed Central's open access journal BMC Biology. This beautiful 'molecular fossil' has a remarkably slow mutation rate meaning that its mitochondrial genome has remained largely unchanged since the dinosaurs were roaming the earth.

Evolutionary studies make used of mitochondrial (powerhouse) genomes to identify maternal lineages, for example the human mitochondrial Eve. Among plants, the lack of genomic data from lineages which split away from the main evolutionary branch early on has prevented researchers from reconstructing patterns of genome evolution.

L. tulipifera is native to North America. It belongs to a more unusual group of dicotyledons (plants with two seed leaves) known as magnoliids, which are thought to have diverged early in the evolution of flowing plants.

By sequencing the mitochondrial genome of L. tulipifera, researchers from Indiana University and University of Arkansas discovered that its mitochondrial genome has one of the slowest silent mutation rates (ones which do not affect gene function) of any known genome. Compared to humans the rate is 2000 times slower – the amount of genomic change in a single human generation would take 50,000 years for the tulip tree. The rate is even slower for magnolia trees, taking 130,000 years for the same amount of mitochondrial genomic change.

Ancestral gene clusters and tRNA genes have been preserved and L. tulipifera still contains many genes lost during the subsequent 200 million years of evolution of flowering plants. In fact one tRNA gene is no longer present in any other sequenced angiosperm.

Prof Jeffrey Palmer who led this study explained, "By using the tulip tree as a guide we are able to estimate that the ancestral angiosperm mitochondrial genome contained 41 protein genes, 14 tRNA genes, seven tRNA genes sequestered from chloroplasts, and more than 700 sites of protein editing. Based on this, it appears that the genome has been more-or-less frozen in time for millions and millions of years."

###

Media Contact

Dr Hilary Glover
Scientific Press Officer, BioMed Central
Mob: +44-0-778-698-1967

Notes

1. The "fossilized" mitochondrial genome of Liriodendron tulipifera: Ancestral gene content and order, ancestral editing sites, and extraordinarily low mutation rate

Aaron O Richardson, Danny W Rice, Gregory J Young, Andrew J Alverson and Jeffrey D Palmer

BMC Biology 2013, 11:29 doi:10.1186/1741-7007-11-29

Commentary

Mitochondrial genomes as living 'fossils'

Ian Small

BMC Biology 2013, 11:30 doi:10.1186/1741-7007-11-30

Please name the journal in any story you write. If you are writing for the web, please link to the article. All articles are available free of charge, according to BioMed Central's open access policy.

Article citation and URL available on request on the day of publication.

Please credit images to Gary Coté, Radford University

2. BMC Biology is the flagship biology journal of the BMC series, publishing peer-reviewed research and methodology articles of special importance and broad interest in any area of biology, as well as reviews, opinion pieces, comment and Q&As on topics of special or topical interest. @BMCBiology

3. BioMed Central (http://www.biomedcentral.com/) is an STM (Science, Technology and Medicine) publisher which has pioneered the open access publishing model. All peer-reviewed research articles published by BioMed Central are made immediately and freely accessible online, and are licensed to allow redistribution and reuse. BioMed Central is part of Springer Science+Business Media, a leading global publisher in the STM sector. @BioMedCentral

.
"I love science and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awe by nature. Science is not meant to cure us of mystery, but to reinvent and revigorate it." by Robert M. Sapolsky

User avatar
dbhguru
Posts: 4484
Joined: Mon Mar 08, 2010 9:34 pm

Re: Tuliptree DNA

Post by dbhguru » Mon Apr 15, 2013 11:12 am

ED,

Three cheers for the tuliptree! Hip hip hooray, etc., etc. The species has always been one of my favorites. For a species to persist in more or less the same form for such lengthy time periods is mightily impressive. Thomas Jefferson considered the tuliptree to be the "Juno of tree species". Others are not so gracious. I've heard people say that they hate the species. Why? No idea.

Bob
Robert T. Leverett
Co-founder, Native Native Tree Society
Co-founder and President
Friends of Mohawk Trail State Forest
Co-founder, National Cadre

User avatar
Bart Bouricius
Posts: 562
Joined: Sat Apr 17, 2010 9:41 am

Re: Tuliptree DNA

Post by Bart Bouricius » Tue Apr 16, 2013 8:13 am

This is quite interesting. As I have not kept up with gene sequencing advances. This tells me that some of the early assumptions involving the relatively consistent rate of change in RNA across similar organisms were not accurate. I have always been fascinated by the development of methodologies permitting glimpses of the ancient past.

User avatar
Larry Tucei
Posts: 2014
Joined: Tue Mar 09, 2010 10:44 am

Re: Tuliptree DNA

Post by Larry Tucei » Tue Apr 16, 2013 8:38 am

Ed- That is so cool- 50,000 years for the species to change a blink of an eye in time. You like to do such research- good job! What would you think the maximum girth of this ancient species would have been or could be? Maybe 10-12' Dia in the past or present? Bob, Bart, Ed, all? Larry

Post Reply

Return to “Tree Species, Families and Identification”