Toward a Biology Worthy of Life > How Biologists Lost Sight of the Meaning of Life > Brief excerpt
A project by Stephen L. Talbott

The molecules in our cells “know” where they’re going

Referring to the “huge number of potentially regulatory elements in a very crowded nucleus”, University of Massachusetts geneticist Job Dekker wonders “How do cells ensure that genes only respond to the right regulatory elements while ignoring the hundreds of thousands of others” (2013).

It’s a good and obvious question. And an editor of Science, summarizing the gist of some recent research, amplifies it this way: “If you think air traffic controllers have a tough job guiding planes into major airports or across a crowded continental airspace, consider the challenge facing a human cell trying to position its proteins”. A given cell, he notes, may make more than 10,000 different proteins, and typically contains more than a billion protein molecules at any one time. “Somehow a cell must get all its proteins to their correct destinations — and equally important, keep these molecules out of the wrong places”. And further: “It’s almost as if every mRNA [an intermediate between a gene and a corresponding protein] coming out of the nucleus knows where it’s going” (Travis 2011).

As I have just noted, there’s not much sense in saying particular molecules “know” where they are going. But the context they find themselves in certainly embodies and gives expression to a kind of wisdom that proves highly effective in coordinating their movements.

bullet Locate this passage inHow Biologists Lost Sight of the Meaning of Life