Toward a Biology Worthy of Life > From Physical Causes to Organisms of Meaning > Brief excerpt
A project by Stephen L. Talbott

Who is sculpting whom?

Carroll repeatedly talks about how various genes “sculpt” a fly’s wings (and various anatomical structures of other animals)...But it’s obvious enough that a section of a DNA molecule does not “sculpt” anything. In fact, the research emphasis today is in the reverse direction: how do proteins and the overall activity of the cell sculpt the genes and chromosomes? Studies on the three-dimensional organization of chromosomes in the nucleus are all the rage, and it is widely recognized that this organization reflects how the organism is making use of its genes. In trying to understand gene expression, biologists “are looking for answers” by studying how the chromosome “folds, moves and communicates” (Baker 2011).

As this last remark indicates, we’re not talking about a static sculpture. In a 2003 article in Nature entitled “Beyond the Double Helix”, Helen Pearson interviewed many geneticists in order to assemble the emerging picture of DNA. One research group, she reported, has shown the molecule “to gyrate like a demonic dancer”. Others point out how chromosomes “form fleeting liaisons with proteins, jiggle around impatiently, and shoot out exploratory arms”. Phrases such as “endless acrobatics”, “subcellular waltz”, and “twirls in time and space” are strewn through the article. “The word ‘static’ is disappearing from our vocabulary”, remarks Tom Misteli of the National Cancer Institute in Bethesda (Pearson 2003). Countless extra-chromosomal factors contribute to this dynamic performance.

The activity of individual genes reflects the choreography of chromosomes, which reflects the larger choreography of the nucleus, which reflects the choreography of the cell and organism as a whole. Who, then, is sculpting whom?

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