Word: rna
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Dates: during 1960-1969
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Jacob and Monod carried this line of experimentation further, discovered that a macromolecule of DNA itself does not tell the cell what substances to manufacture. Instead, it makes a partial copy of itself, called "messenger RNA," to execute its orders. The Jacob-Monod hypothesis goes on to suggest that a second or "operator" gene, also present in the DNA, may work with the basic gene in a complex feed-back mechanism. And there may even be a third type of gene...
...whether an organism is to be microbe, mouse or man, its biochemical functions are determined by genes strung together to form chromosomes. Each gene is believed to be a submicroscopic but still "giant" molecule of a nucleic acid, usu ally deoxyribonucleic acid (DNAJ, but in some viruses ribonucleic acid (RNA) Each gene, the theory held, directly controls the cells' production of some one specific chemical-in most cases an enzyme, one of the body's countless catalysts that are essential to nearly all its functions...
...creatures called planarians, or flatworms, that he has published in his own journal, The Worm Runner's Guide, and elsewhere. His work, which has been confirmed by only some of the researchers who have tried to duplicate his expermiments, suggests that memory storage is in some way related to RNA, the gigantic molecule which is also involved in cell reproduction. He exploited the remarkable regenerative powers of the planarian to demonstrate that both halves of a bisected worm will contract in the presence of light if the worm has been so conditioned before the operation is performed. In his words...
...Rubin, once a postdoctoral fellow in Dr. Dulbecco's lab, worked with viruses that cause leukemia in fowl and have a nucleus consisting of ribonucleic acid (RNA). The work of these men, said the awards committee, "promises to contribute decisively to our eventual understanding of the nature of cancer...
...only those parts of the DNA molecule that contain a few items of chemical instructions needed for metamorphosis. The parts become suddenly active; they swell up, forming visible puffs which show that the hormone has told them to do their stuff. Dutifully they release their information by forming "messenger RNA" (ribonucleic acid) that diffuses into the body of the cell and manufactures the protein enzymes that bring about metamorphosis. Then the puffs disappear, and the chromosomes wait for other hormones to come along and tell them to release other items of information...