Tag Archives: cellular structure

New Study Outlines ‘Water World’ Theory of Life’s Origins

Life took root more than four billion years ago on our nascent Earth, a wetter and harsher place than now, bathed in sizzling ultraviolet rays. What started out as simple cells ultimately transformed into slime molds, frogs, elephants, humans and the rest of our planet’s living kingdoms. How did it all begin?

A new study from researchers at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the Icy Worlds team at NASA’s Astrobiology Institute, based at NASA’s Ames Research Center in Moffett Field, Calif., describes how electrical energy naturally produced at the sea floor might have given rise to life. While the scientists had already proposed this hypothesis — called “submarine alkaline hydrothermal emergence of life” — the new report assembles decades of field, laboratory and theoretical research into a grand, unified picture. (more…)

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Analysis of Dinosaur Bone Cells Confirms Ancient Protein Preservation

A team of researchers from North Carolina State University and the Palo Alto Research Center (PARC) has found more evidence for the preservation of ancient dinosaur proteins, including reactivity to antibodies that target specific proteins normally found in bone cells of vertebrates. These results further rule out sample contamination, and help solidify the case for preservation of cells – and possibly DNA – in ancient remains.

Dr. Mary Schweitzer, professor of marine, earth and atmospheric sciences with a joint appointment at the North Carolina Museum of Natural Sciences, first discovered what appeared to be preserved soft tissue in a 67-million-year-old Tyrannosaurus Rex in 2005. Subsequent research revealed similar preservation in an even older (about 80-million-year-old)Brachylophosaurus canadensis. In 2007 and again in 2009, Schweitzer and colleagues used chemical and molecular analyses to confirm that the fibrous material collected from the specimens was collagen. (more…)

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Yale Study: How Mitochondrial DNA Defects Cause Inherited Deafness

Yale scientists have discovered the molecular pathway by which maternally inherited deafness appears to occur: Mitochondrial DNA mutations trigger a signaling cascade, resulting in programmed cell death. The study is in the Feb. 17 issue of Cell.

Mitochondria are cellular structures that function as “cellular power plants” because they generate most of the cell’s supply of energy. They contain DNA inherited from one’s mother. Mitochondria determine whether a cell lives or dies via the process of programmed cell death, or apoptosis. (more…)

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