DNA: New Methods Yield Mammoth Samples

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Authors: Ann Gibbons
Media: Science mag
Date: December 2005

Ancient DNA has always held the promise of a visit to a long-vanished world of extinct animals, plants, and even humans. But although researchers have sequenced short bits of ancient DNA from organisms including potatoes, cave bears, and even Neandertals, most samples have been too damaged or contaminated for meaningful results.

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American Museum of Natural History biologist and colleagues decode longest DNA sequence ever of woolly mammoth

American Museum of National History

Authors: Department of Communications
Media: American Museum of Natural History
Date: December 2005

Finding demonstrates that sequence of entire woolly mammoth genome is within reach
An American Museum of Natural History biologist and his colleagues have completed a painstaking project that allowed them to decode the largest piece by far of the genome of the woolly mammoth, the shaggy, extinct elephant relative that ranged far and wide on Earth until the end of the last Ice Age about 10,000 years ago.

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Mammoth plan for giant comeback

Authors: Roger Highfield
Media: Telegraph.co.uk
Date: December 2005

The first serious possibility that the woolly mammoth, or something like it, could walk on Earth again was raised yesterday by an international team of scientists. A portion of the genetic code of the mammoth has been reconstructed and, to the surprise of scientists, the team that carried out the feat believes that it will be possible to decode the entire genetic make-up.

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Tarsus determination in Drosophila melanogaster

Authors: A. Percival-Smith, W.A. Teft and J.L. Barta
Journal: Genome – 48(4):712-721 (2005)

Arista versus tarsus determination is well investigated in Drosophila, yet it remains unresolved whether Antennapedia (ANTP) cell autonomously or noncell autonomously determines tarsus identity and whether Sex combs reduced (SCR) is the HOX protein required for normal tarsus determination. Three observations rule out a cell autonomous role for ANTP in tarsus determination. (i) Clonal ectopic overexpression of ANTP did not repress the expression of the arista determining protein Homothorax (HTH) in early 3rd stadium antennal imaginal discs. (ii) Clonal ectopic expression of ANTP did not transform the arista to a tarsus. (iii) Ectopic overexpression of ANTP, Labial (LAB), Deformed (DFD), SCR, Ultrabithorax (UBX), Abdominal-A (ABD-A), or Abdominal-B (ABD-B), using the dppGAL4 driver, resulted in arista-to-tarsus transformations, and repressed HTH/Extradenticle (EXD) activity noncell autonomously in early 3rd stadium antennal imaginal discs. SCR may not be the HOX protein required for normal tarsus determination, because co-ectopic expression of Proboscipedia (PB) inhibited the arista-to-tarsus transformations induced by ectopic expression of DFD, SCR, ANTP, UBX, ABD-A, and ABD-B. The proposal that SCR is the HOX protein required for normal tarsus determination is dependent on SCR being the sole target of PB suppression, which is not the case. Therefore, the possibility exists that normal tarsus determination is HOX independent.

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Osteocalcin protein sequences of Neanderthals and modern primates

Authors: Christina M. Nielsen-Marsha,b, Michael P. Richardsa,c, Peter V. Hauschkad, Jane E. Thomas-Oatese, Erik Trinkausf, Paul B. Pettittg, Ivor Karavanic´h, Hendrik Poinar, and Matthew J. Collins
Journal: PNAS | vol. 102, no. 12, 4409–4413

We report here protein sequences of fossil hominids, from two Neanderthals dating to ~75,000 years old from Shanidar Cave in Iraq. These sequences, the oldest reported fossil primate protein sequences, are of bone osteocalcin, which was extracted and sequenced by using MALDI-TOF/TOF mass spectrometry. Through a combination of direct sequencing and peptide mass mapping, we determined that Neanderthals have an osteocalcin amino acid sequence that is identical to that of modern humans. We also report complete osteocalcin sequences for chimpanzee (Pan troglodytes) and gorilla (Gorilla gorilla gorilla) and a partial sequence for orangutan (Pongo pygmaeus), all of which are previously unreported. We found that the osteocalcin sequences of Neanderthals, modern human, chimpanzee, and orangutan are unusual among mammals in that the ninth amino acid is proline (Pro-9), whereas most species have hydroxyproline (Hyp-9). Posttranslational hydroxylation of Pro-9 in osteocalcin by prolyl-4-hydroxylase requires adequate concentrations of vitamin C (L-ascorbic acid), molecular O2, Fe2+, and 2-oxoglutarate, and also depends on
enzyme recognition of the target proline substrate consensus sequence Leu-Gly-Ala-Pro-9-Ala-Pro-Tyr occurring in most mammals.
In five species with Pro-9–Val-10, hydroxylation is blocked, whereas in gorilla there is a mixture of Pro-9 and Hyp-9. We suggest that the absence of hydroxylation of Pro-9 in Pan, Pongo, and Homo may reflect response to a selective pressure related to a decline in vitamin C in the diet during omnivorous dietary
adaptation, either independently or through the common ancestor of these species.

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