Articles Archive for September 2009
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Chine unearthed another gem in the form of a four winged dinosaur , Anchiornis huxleyi. Its dated to the Late Jurassic period, 151-161 million years ago making it oldest winged species, the 150-million-year-old Archaeopteryx lithographica, found more than a century ago in Germany. Hence this new discovery of the oldest known bird, provides more hard evidence that birds evolved from dinosaurs.
Chinese scientists discovered five remarkable new feathered dinosaur fossils from two separate areas, named the Tiaojishan and Daohugou formations. Comparison of the Tiaojishan and Daohugou fossils suggests that they …
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India is second most populous country and makes up around one-sixth of the world’s population, yet it has been sorely under-represented in genome-wide studies of human genetic variation. Recently a group led by Lalji Singh of the Centre for Cellular and Molecular Biology in Hyderabad, India and David Reich of the Broad Institute in Cambridge, Massachusetts, analyzed more than 500,000 genetic markers across the genomes of 132 individuals from 25 diverse groups, representing 13 states, all six language families, traditionally “upper” and “lower” castes, and tribal groups in order …
Evo devo, Signalling »
Hedgehog family of signaling proteins are pivotal for growth, patterning, and morphogenesis during embryonic development of vertebrates and many invertebrates. The hedgehog signaling pathway is one of the key regulators of animal development conserved from flies to humans. The Drosophila hedgehog gene was identified as one of several genes important for creating the differences between the anterior and posterior parts of individual body segments in the famous genetic screen of Nusslein-Volhard and Eric Wieschaus during late 70′s. It was named Hedgehog because a larva which lacked this protein completely …
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Remember once i posted a video on High speed sequencing by Helicos and today i came across an wonderful review article ( Thanks to sandwalk blog by larry Moran) on next generation DNA sequencing. This review appeared in Nature biotechnology and written by Jay Shendure and Hanlee Ji. This review gives an nice overview about Sanger sequencing, 454 sequencing, Solexa technology and helicos technology.
Some related videos :
Helicos High Speed sequencing :
Next-generation DNA sequencing
Shendure J, Ji H.
Nat Biotechnol. 2008 Oct;26(10):1135-45.
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Thomas Hunt Morgan is regarded as father of modern Drosophila genetics and today September 25 is his birthday. Born in 1866 at Lexington, Kentucky, U.S.A, Morgan is regarded as one of finest embryologists and Geneticist of all time , famous for his experimental research with the fruit fly “Drosophila”. He graduated from the State College of Kentucky (now University of Kentucky) in 1886 and received his Ph.D. from Johns Hopkins University in 1890. It was in the year of 1909 he started working on the fruitfly Drosophila melanogaster with …
Evo devo »
The latest issue of science journal reports a new discovery, a 9-foot dinosaur fossil from northeastern China by Paul Sereno and colleagues.This new fossil is named “Raptorex kriegsteini” , displays all the features of giant Tyrannosaurus rex and it predates the T. rex by tens of millions of years.
Paul Sereno from the University of Chicago and National Geographic explorer-in-residence, along with colleagues, studied the new, small-bodied fossil, naming it Raptorex kriegsteini, and estimated that it was a young adult when it died. They examined the skull, teeth, nose, spine, shoulders, …
Evo devo »
Andrew Sinclair’s group in Murdoch children research institute in Australia deciphered the mechanism involved in avian sex determination, which has been a long-standing mystery in the field of developmental biology. Prof Sinclair’s group focuses on sex determination, and aims to understand how genes control gonad development. Development of the gonads (testes or ovaries) requires the coordinated functioning of many genes and proteins.
Sex determination in Birds like mammals is chromosomally depended but sex chromosomes as well as mechanism is largely different. All males in Birds possess have two Z chromosomes while …