As ENV mentioned earlier today, our neighbor the Microsoft billionaire Paul Allen has just invested $100 million in a new center devoted to trying to illuminate how cells work. What, you thought scientists had that all figured out? Hardly, and his investment stands as a demonstration of how much remains unknown despite claims to the contrary.

Meanwhile our colleague biologist Ann Gauger has an admirably clear and accessible new essay in a Christianity Today publication, The Behemoth, which explores the mystery and magnificence of the natural world. (The title is a reference to Job. Look it up.) Dr. Gauger’s essay, "Mystery at the Heart of Life: The Secret Life of Cells," is accessible in the sense of being remarkably lucid and digestible by the layman — she has a gift for that.

Unfortunately it’s not accessible in the sense that it’s behind a paywall. I can share some of it though. She aptly compares the cell, of which your body includes 100 trillion, to the most hectically active urban environment you can imagine, like Hong Kong on speed.

We tend to think of cells as static, because that’s how they were presented to us in textbooks. In fact, the cell is like the most antic, madcap, crowded (yet fantastically efficient) city you can picture. And at its heart lies a mystery — or I should say, several mysteries — involving three special kinds of molecules: DNA, RNA, and proteins.

These molecules are assembled into long chains called polymers, and are uniquely suited for the roles they play. More importantly, life absolutely depends upon them. We have to have DNA, RNA, and protein all present and active at the same time for a living organism to live.

How they work together so optimally and efficiently is not merely amazing, but also a great enigma, a mystery that lies at the heart of life itself.

Dr. Gauger details some of those workings, concluding with a pair of evolutionary conundrums, seemingly inexplicable in Darwinian terms, the first familiar, the second less so:

You may have noticed that these proteins are all generated by the DNA — as we have seen, DNA is copied into RNA, then RNA is translated into protein.

Consequently, proteins cannot exist without DNA. 

However, DNA cannot exist without proteins either.

For example, to replicate DNA, one protein unwinds the DNA, creating a fork with two strands; another protein duplicates the right strand of the DNA, while yet another casts off loops from the left strand so it can be copied. Meanwhile, thirty or so other proteins keep watch over the DNA, proofreading, correcting, and ensuring very few errors — about one mistake per billion nucleotides copied.

In short, it’s a chicken and egg problem: which came first, proteins or DNA?

Even if that problem could be solved, another puzzle would remain: how the link between DNA, RNA, and protein came about. We know how it’s done — ribosomes — but we have no idea how ribosomes came to be. Ribosomes are indispensable, efficient, self-correcting, decoding machines, and protein factories. They are made of many proteins woven together with RNA molecules into tangled knots that somehow work together to decode RNA. In fact, just deciphering into what shape those knots are tied won three scientists the 2009 Nobel Prize in Chemistry.

Born in the nucleus, ribosomes do their work in the cytoplasm. Messenger RNA (RNA copied from a protein-coding gene) finds a ribosome and begins feeding through like ticker tape. The ribosome reads the message and translates it into amino acids, stitching the amino acids together to make a protein.

Though not as fast as transcription, the ribosome manages a respectable rate of 6 to 9 amino acids per second, a little faster than the best of our typists. But consider this: there are 20-plus amino acids for the ribosome to sort through in order to find the right one for each unit to be translated. Given that kind of search process, 6 to 9 amino acids per second puts the ticker tape on fast forward.

One last thing — the ribosome is also self-correcting. As the protein advances, the ribosome double-checks its work, and if it notices a mistake, it backs up to correct the error, like I had to do as I typed this sentence.

Suffice it to say that the genetic code, and the fidelity of its replication, transcription, and translation, are obviously very important, considering all the error correction that goes on, and they are interdependent, highly optimized processes that are essential to life. At the very center of these processes is this mystery: which came first, the protein or the DNA? And how was the link between DNA and protein established? Some say RNA came first, but RNA is inherently unstable, easily degraded and limited in its chemical abilities. So the problem remains unsolved.

We may someday figure out some of these relationships, but as is the nature of things, more mysteries will be revealed as we do. In fact, it may well be that at the very center of life, of existence itself, there lie mysteries known only to God. In the meantime, though, God has given us both the ability and the desire to search out the truth about things. For as Proverbs 25:2 says, "It is the glory of God to conceal a matter; to search out a matter is the glory of kings."

If you subscribe to The Behemoth, which I recommend, you can read the rest.

Image: By IP69.226.103.13 (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons.