Dinosaur protein sequenced - Lucky find shows up record-breaking fossil.

news@nature.com ^ | 12 April 2007 | Heidi Ledford

[neverdem]

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Published online: 12 April 2007; | doi:10.1038/news070409-11

Dinosaur protein sequenced

Lucky find shows up record-breaking fossil.

Heidi Ledford

Digging through the rock in Montana yielded the surprise find. Science

Palaeontologists have sequenced some protein from a 68-million-year-old fossilized Tyrannosaurus rex bone.

The protein — a key component of bone and connective tissue called collagen — blasts the record for the oldest protein ever sequenced. Before this, the oldest sequenced protein (also collagen) came from a mammoth fossil that was 100,000-300,000 years old. So the new find, reported this week in the journal Science¹, is quite a surprise.

Scientists hope that if similar molecular data can be recovered from other fossils, the information can be used to firm up the dinosaur family tree and to better understand their relationship with living animals.

But evolutionary biologists caution that the information from a single type of protein, such as collagen, is inadequate for building a proper family tree.

Nor is sequencing a single type of protein going to open the doors to Jurassic Park. Scientists would need DNA — which is much more fragile — in order to get the full genome of an ancient animal.

"I think it's a really great experiment," says Mark Norell of the American Museum of Natural History in New York. "But is this going to change the way we look at dinosaurs? Well, probably not."

Hard core protection

Many paleontologists don't think to check their fossils for protein, says palaeontologist Mary Higby Schweitzer of North Carolina State University in Raleigh, a co-author on the study. It's been known for a long time that dinosaurs exhibit wonderful microstructural preservation," she says. "However, it's always been assumed that preservation does not extend to the cellular or molecular level."

If we can only get rare sequence data it will remain just a curiosity  Derek Briggs, Yale University's Peabody Museum of Natural History.

This particular fossil, which has been shown to contain soft tissues before (see 'Flexible fossil shows tyrannosaur's softer side'), was unusually well preserved.

It was found within 1,000 cubic metres of sandstone in the badlands of eastern Montana. The rock is thought to have kept away damaging groundwater and bacteria. "As the tissues begin to liquefy, the enzymes of decay and degradation are drained away in the sand, whereas in the mud it just sits and stews in its own juices," says Jack Horner, a palaeontologist at the Museum of the Rockies at Montana State University in Bozeman and an author on the study.

Collagen is very abundant and collagen fibres form a particularly tough, triple helix, with three strands of protein wound together like rope. The collagen samples that Schweitzer isolated from the T. rex fossil were buried deep within the fossil's large, dense bones, which probably provided a protective casing for the protein.

No one thought protein from a 68-million-year-old bone could be preserved. Science

Horner is optimistic that similarly well-preserved fossils and their resident proteins can be isolated if palaeontologists are willing to dig through enough rock to find them. "If we spend a lot of time getting as deep into the sediment as we can in places where there has been very little air or water contamination, I think we're going to find that many specimens are like this," he says.

But others question whether there will be enough such finds to be useful. "I think you're not going to be able to get this kind of material from the vast majority of fossils," says Norell. "Most of the stuff we work on has been heated to hundreds and hundreds of degrees and smashed by geological pressure."

"If we can only get rare sequence data it will remain just a curiosity," says Derek Briggs, a curator at Yale University's Peabody Museum of Natural History in New Haven, Connecticut.

Close to a chicken

So far, seven fragments of protein sequence have been gleaned from the T. rex fossil. Trawling through the limited amount of data available on collagen sequences, the authors determined that these are closest to the collagen of chickens².

This is in keeping with the dominant view that birds and dinosaurs are closely related. But the researchers hasten to point out that this does not mean that T. rex's closest modern relative is the chicken — just that the chicken is the closest relative for which collagen sequence is available in public databases. Crocodile and alligator collagen sequences, for example, were not available for comparison.

Schweitzer hopes the results will also encourage palaeontologists to open their collections to molecular investigation — even though that will mean dissolving the samples to get at any proteins inside. "Most curators of dinosaur palaeontology don't like me," says Schweitzer. "They like to keep their bones intact."

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References

1. Schweitzer M. H., et al. Science, 316 . 277 - 280 (2007).
2. Asara J. M., et al. Science, 316 . 280 - 285 (2007).

[neverdem]

Analyses of Soft Tissue from Tyrannosaurus rex Suggest the Presence of Protein

Protein Sequences from Mastodon and Tyrannosaurus Rex Revealed by Mass Spectrometry

Like before, the text is available and miniature figures are in "Figures Only" and pdf links are given for the "Supporting Online Material."

[Diogenesis]

I want a Tyrannoburger ... tastes like chicken.

[Maelstorm]

Interesting. I’d been reading about soft tissue extraction from dinosaur bones for a while. This is the first time I’ve heard of any sequencing.

[Savage Beast]

"If we spend a lot of time...I think we're going to find that many specimens are like this."

That's right, Jack. And one of these days you're going to stick in your thumb and pull out a plumb and say: "Holy Mackerel! This is Dinosaur DNA!" And you know what'll happen next!

If you think alligators are a problem, just wait!

[Savage Beast]

Good news for Colonel Sanders!

[Poundstone]

Next stop: Jurassic Park!

[neverdem]

Here are two other threads on the story.

Scientists Retrieve Proteins From Dinosaur Bone

Ancient T. rex and mastodon protein fragments discovered, sequenced There are many links from Sunken Civ.

Howard says no to HIV-positive immigrants (Australia)

Restoration of p53 function leads to tumour regression in vivo This pdf link is quite fascinating, although it's a very technical 5 pages. I noticed the title on Nature's home page. I found this copy posted on the web.

FReepmail me if you want on or off my health and science ping list.

[mountainlyons]

Is this the same sample that was softened with vinegar?

[WorkingClassFilth]

This particular fossil, which has been shown to contain soft tissues...

Seventy five million years old.

BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA!

[TigersEye]

ping

[Psycho_Bunny]

It sure as heck isn’t 6,000 years old.

[Kevmo]

fascinating. bump for later reading

[WorkingClassFilth]

I don’t know, frankly, but I sure as hell know that it ain’t 75 million years old. My sandwhich in my lunchpail gets dry between 5:00 am when it is made and 12:00 noon when I eat it. Somebody’s full of sh*t.

[neverdem]

I don’t know, frankly, but I sure as hell know that it ain’t 75 million years old. My sandwhich in my lunchpail gets dry between 5:00 am when it is made and 12:00 noon when I eat it. Somebody’s full of sh*t.

"Palaeontologists have sequenced some protein from a 68-million-year-old fossilized Tyrannosaurus rex bone."

I believe your problem is with Palaeontology and geology.

These are pdf links:

Supporting Online Material for "Analyses of Soft Tissue from Tyrannosaurus rex Suggest the Presence of Protein"

Supporting Online Material for "Protein Sequences from Mastodon and Tyrannosaurus Rex Revealed by Mass Spectrometry"

[neverdem]

Maybe this link will help.

Soft tissue taken from 68 million-year-old Tyrannosaurus rex fossil yields original protein

[neverdem]

You might be interested in news@nature.com‘s version and some of the links on this thread.

[SunkenCiv]

Thanks!

Ancient T. rex and mastodon protein fragments discovered, sequenced
National Science Foundation | 12-Apr-2007 | Cheryl Dybas
Posted on 04/12/2007 3:43:57 PM EDT by AdmSmith
http://www.freerepublic.com/focus/news/1816333/posts

BBC: Protein links T. rex to chickens ~ ummm tasty....
BBC | Thursday, 12 April 2007, 19:27 GMT 20:27 UK | Paul Rincon Science reporter, BBC News
Posted on 04/12/2007 4:57:11 PM EDT by Ernest_at_the_Beach
http://www.freerepublic.com/focus/f-news/1816370/posts

[TigersEye]

Not a problem. Throw another Tyrannosaurus wing on the barbie for me.

[SunkenCiv]

pre-Tertiary takeout buckets must have been huge.

[SunkenCiv]

Oops, didn’t notice that, thanks!