Barry Commoner's Contribution to the Environmental Movement by Lee Dunn Mary;Kriebel David L.;

Author:Lee Dunn, Mary;Kriebel, David L.;
Language: eng
Format: epub
Publisher: Taylor & Francis Group

Figure 1. DNA double helix.

Watson and Crick had formulated what they called “The Central Dogma of Molecular Biology”—imagine in science calling something a dogma! This designation infuriated me as a starry-eyed graduate student with many idealistic notions about Science. (It still does.)

The message which the Central Dogma was meant to convey is spelled out in the text accompanying the figure (Figure 2) in the 3rd Edition (1976) of Watson’s influential book, The Molecular Biology of the Gene. Two footnotes stated that one-way flow of information, the defining feature of “The Central Dogma,” is not always the case. Despite this, Watson and the molecular biology community continued to use the designation, “The Central Dogma of Molecular Biology.”

As noted, embedded in the Watson/Crick formulation was the idea that DNA was a self-replicating molecule. Barry took considerable exception to this, insisting that no biological unit less complex than a cell was capable of self-replication. In addition, Barry proposed that certain proteins, as well as DNA, played a role in biological inheritance. Finally, he proposed that DNA played more than one role in inheritance. In addition to the DNA in the euchromatic regions being the stuff of genes, Barry hypothesized that the amount of DNA “sequestered” into the heterochromatic region served as a coarse governor of the basal metabolic rate (Figure 3).

The central feature of this “sequestration” theory used the facts that DNA was an extremely stable molecule and the nucleotides which provided the bases in DNA were also crucial co-factors in metabolism. So, the argument went, if these nucleotides were sequestered into stable DNA, they would not be available to power metabolism. I was not a fan of this theory because, as I argued with Barry, the diagram needed one more arrow, an arrow indicating that ATP (adenosine triphosphate) and GTP (guanosine triphosphate) can be synthesized, as well as sequestered.

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