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Re: Osteocalcin and dinosaur DNA
At 11:17 AM 4/23/2003 +0200, David Marjanovic wrote:
Ahoj Vlad...e? :-)
> I was just reading some older postings and would like to ask if there
> is anything new about:
> 1.) Muyzer et al. 1992 study concerning the possibilities of
> detecting and extracting protein osteocalcin from dinosaur bones
> using PCR.
Certainly not. PCR can amplify DNA but not proteins.
> [...] Also the measurements of Gla/Glu ratio showed presence
> of osteocalcin in all three samples.
Is that Gln/Glu (glutamine/glutaminic acid)?
> 2.) "Spherical structures" resembling a red blood cells from T. rex
> (Ph.D. Schweitzer's research).
> Also, is it true that some parts of dinosaur bone (femur?) were not
> mineralised but were in fact original bone? How is that possible
> 65-70 Ma after fossilization?
Do you mean _re_mineralised? This
http://www.dinosauria.com/jdp/fossil/fossil.htm and this
http://www.dinosauria.com/jdp/fossil/fossil.htm might help.
> [...] if we can extract enough osteocalcin material from
> bones of various dinosaur species to do a DNA sequencing
Osteocalcin is a protein and not DNA. But of course proteins can be
> and compare the outcoming sequences
> afterwards, will that reveal e.g. the level of relativness between
> dinosaur species, genera, clades? Could it, hypothetically, resolve
> the taxonomic problems like "Is _Seismosaurus hallorum_ valid genus
> or is it a species of Diplodocus?"
A genericometer! If we manage to agree on a phenetic definition for genera
( :-D ), then perhaps. The usefulness of this is another question...
Ancient proteins are being sequenced using PCRs. Extracting aDNA is not
easy. Indeed, if one looks carefully it is possible to get some nearly
original bone material and cancellous bone from dinosaur specimens that are
70-66.5 Ma. Watch for a very soon upcoming preliminary paper in
BioTechniques......... Primary authors: Barchoon & Wegweiser
Marilyn D. Wegweiser, Ph.D.
Assistant Professor of Geology
Curator, Paleozoic & Mesozoic Collections
Department of Biological and Environmental Sciences
Georgia College & State University
Milledgeville, GA 31061
(works best in Internet Explorer)
Director: This Side Of Hell, WY Research Project; it's north of Pitchfork
Wyoming, north of Hell's Half Acre, Wyoming, west of Hell, North Dakota,
and south of Hellroaring Plateau, Montana. Could it get any better than this?