Word: crick
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...limitless information-storage system, like the memory bank of a computer. In addition, because the bases were chemically complementary?that is, A paired off only with T, and C only with G?one side of the staircase was in effect a genetic mirror image of the other. Watson and Crick quickly recognized from the structure of their model how DNA worked. But their 900-word announcement in Nature, the international weekly published in Britain, concluded with one of the more coy statements in scientific literature. "It has not escaped our notice," they said, "that the specific pairing we have postulated...
...Once he obtained enough of the enzyme, he placed it in a test-tube brew with a bit of natural DNA, one of whose strands was incomplete, the four bases (A, T, C, G) and a few other off-the-shelf chemicals. True to his expectations?and the Watson-Crick theory?the incomplete segment picked up its complementary nucleotides from the brew to form a complete double helix...
Implicit in the Watson-Crick model were the workings of DNA's other essential function: how it orders the production of proteins. These are also long and twisted helical molecules, but they are the actual building blocks rather than the genetic blueprints for living things. As such, proteins are immensely varied; there are many thousands of different kinds in the human body alone. The distinctive proteins that make up the cells of the eye, for example, differ from those of the kidneys or muscles. Despite their variety, however, all proteins are built from some of only 20 smaller and simpler...
...after wrestling with the question, Francis Crick postulated (and Harvard Biochemists Paul Zamecnik and Mahlon Hoagland confirmed) a second form of RNA, which was later found to carry specific amino acids floating in the cytoplasm to the ribosomes; this substance became known as transfer RNA. Then in the early 1960s, biologists discovered a third kind of RNA?shortly after its existence had been theorized by Jacques Monod and François Jacob of France's Pasteur Institute. Called messenger RNA, it provided the missing piece in the molecular puzzle. It was formed on an uncoiled strip of DNA in the nucleus...
...CRICK'S team at Cambridge proved Gamow's ingenious "triplet" theory. They demonstrated that RNA formed from only one or two base units could not effect the manufacture of proteins. But when they added a third base unit, protein formation began immediately. It remained, however, for an unknown young biochemist named Marshall Nirenberg, at the National Institutes of Health, to crack the code itself. That same year Nirenberg had succeeded in building up short, synthetic strands of RNA out of only one type of base. Invariably, this artificial RNA induced the manufacture of chains of proteins consisting of only...