Friday, January 18, 2008

Cellular Master Craftsmen

Let's contemplate one more chemical wonder of the cell in the hope of converting some "ho-hums" to "wows" in the world of the very small. Imagine a master architect's blueprints for the world's most magnificent building -- complete, detailed specifications for thousands of exquisite, hand-worked ornamental features in addition to the building's basic structure and function. Such a blueprint from a master architect would be remarkable in itself, but of little use without master foremen and master builders to implement the plans.

The building's blueprint is like the cell's DNA containing all the organism's genetic information. DNA is able to replicate -- make a copy of itself -- but what else can it do? It synthesizes messenger RNA (mRNA) by a similar replicating process called transcription. mRNA then carries messages to the protein building machinery of the cell, much like the building foremen communicate information to the construction workers. Then, through a process called translation and the help of other types of RNA, proteins are put together, analagous to the activities of the master craftsmen on the construction team.

What are proteins? How are they put together? And what are they for? Proteins are various combinations of amino acids. There are only twenty amino acids used in protein building. If you think of each amino acid as a letter in a game like Scrabble, there are endless combinations of letters which could form an unlimited number of words if we had unlimited Scrabble tiles and no limit on how long the word could be. RNA directs the formation of tens of thousands of proteins in our bodies, each with a specific structure and function ranging from support, to storage, transport, communication, movement, and defense. Just as there are millions of words possible by combining and repeating some of our 26 alphabet letters in various ways, there are millions of proteins to be formed from just twenty amino acids.

Does anyone wonder why living things display such diversity, beauty, and functionality? RNA's "master craftsmen" know exactly what raw materials to use and what products to fabricate in the construction process. Wonderful as the information-rich system of DNA is, analagous to a computer's invisible memory capability, RNA is actually much more versatile, like a computer's communication capability together with the printer's ability to generate visible, recognizable pictures or meaningful literature in the final step of its process sequence. The computer system's final printed product gets the "oohs" and "aahs." When we contemplate the variety of human life and achievement, not to mention all categories of biological life surrounding us, we cannot help but renew our sense of wonder, perhaps with "oohs" and "aahs" and cheers for the Master Architect.