Word: proteins
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Dates: during 1970-1979
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...would such genetic repetition help man? Some theorists suspect that the "spare" DNA plays a regulatory role, perhaps switching other genes on and off at just the right moment during the involved process of protein manufacturing. Harvard Biochemist Charles Thomas, however, supports a more radical idea. He thinks that the repeated segments are actually "slaves" of a "master" gene from which they have been copied. Working in tandem, explains Thomas, such "slaves" could produce proteins more quickly and efficiently?though, he admits, not necessarily in greater diversity...
...from a hair cell, a heart cell so different from a skin cell? The answer, Jacob and Monod theorized in 1961, is that only a small percentage of the genes in any cell are giving instructions for the operation of that particular cell. The rest are "turned off" by protein repressers, which wrap themselves around long stretches of DNA and prevent them from transferring their coded information to messenger...
...CONCEPT IS not as farfetched as it sounds. Real viruses are merely segments of DNA (or RNA) surrounded by largely-protein sheaths; they penetrate the cell nucleus (leaving their sheaths behind) and take over the cellular...
Researchers have found that they can increase the life span of laboratory animals by underfeeding them and thus delaying maturation. This phenomenon, they believe, occurs because a smaller intake of food results in the formation of fewer cross linkages?connecting rods that link together and partly immobilize the long protein and nucleic acid molecules essential to life. If scientists can retard cross linking in man, they may well slow his aging process. Scientists also hope that they can some day do away with disease, genetically breeding out hereditary defects while breeding in new immunities to bacterial and other externally caused...
That something, theorists believed, was chemical. Scientists had long known that chemical as well as electrical activity goes on in brain neurons: these cells carry on metabolism and protein synthesis like other body cells. Researchers soon learned that the leap of message-carrying nerve impulses across the gap between one cell and another takes place only with the help of chemical transmitter substances. One of these, acetylcholine, was promptly identified, and investigators began to look for other brain chemicals, specifically for varieties that might contain memories...