Word: rna
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...Biochemistry professor and RNA researcher Joan Argetsinger Steitz...
Steitz, a professor of biochemistry at YaleMedical School, is known for her discovery ofsmall ribonuclear proteins--called SNURPS--thatare important in RNA splicing, said Professor ofBiochemistry and Molecular Biology Tom Maniatis...
...these things alive? That depends on how the term is defined. Surprisingly, there is no clear definition of "life." Most of the criteria put forward in the past are anthropocentric. Life on earth is carbon-based and built around the nucleic acids RNA and DNA, but that may be a historical accident. Most living things metabolize and multiply, but not all. Viruses have no metabolisms of their own; mules cannot reproduce. Many living things grow, but so do clouds and garbage dumps...
Working with a bacterium and a pond-dwelling protozoan, Altman, 50, and Cech, 41, independently discovered that RNA can act as an enzyme, a molecule that accelerates chemical reactions a millionfold or more and makes it possible for life to exist. Plants, for example, depend on enzymes to convert carbon dioxide in the air to sugar and starch. An enzyme in human saliva helps transform starch into glucose, the body's energy source. Until RNA enzymes were identified, all enzymes were thought to be proteins...
Cech also found that RNA can copy itself, suggesting that the first living organisms may not have depended solely on DNA, the principal carrier of hereditary information in plants, animals and bacteria. "Now that we know that RNA can both carry genetic information and serve as a catalyst," Cech wrote last year, "it seems possible that it was the key molecule at the origin of life...