Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology
What I’ve Learned:

Viroid: the simplest is as the simplest does.
“Viroid: the simplest is as the simplest does.”

Everyone I know is trying to “simplify”, in any way they can. They’re downsizing their houses. Giving away old clothes. Cutting out cable. (But not Netflix, because come on, Unbreakable Kimmy Schmidt, already.)

Pretty much anything short of donating their kids to science and moving into a zen garden, these people are doing in the name of simplicity. And you know what?

They’re amateurs.

Because how “simple” are you, really, when you’re still human? There are all sorts of complicated things going on inside us — and I’m not just talking about our Facebook relationships or the way we feel about Charlie Kaufman films.

Human bodies are all kinds of intricate. You’ve got circulatory systems and immune cells, respiratory tracts and reproductive organs — and that’s just the tip of the person-berg. “Simplify” all you like, but if you’re holding on to all that bodily baggage — with your fingers; don’t even get me started on fingers — then you’re not very simple at all.

And what’s more, if you think you need all of that — or any of it — to live in the world, grow up and pass on your genetic material, then you’re wrong. You can do all that with less. Much less. If you really want to simplify, take a cue from a viroid.

Viroids are about as small — and simple — as a reproducing bit of schmutz can get. Classified as “sub-viral pathogens”, viroids have almost none of the fiddly biological bits even most tiny organisms hold dear. Take amoebas, for instance; these microscopic little one-celled critters still have tiny tails to move around with, a way to take in nutrients and a nucleus for their genome. Ain’t no viroids got time for that.

Bacteria are even smaller than amoebas, but they at least have a cell membrane, and enzymes and stuff kept handy in pockets, for when they’re needed. Viroids got no enzymes, no pockets, and no cell to keep them in.

Viruses are tinier still, and are mostly just made up of a few genes on a strip of DNA. But at least — at least, for crissakes — they have the decency to cover up their genetic material with a membrane of some kind, and to code for a protein or two.

But viroids? Nuh uh. They’re nothing but naked RNA, single-stranded genetic material all folded in on itself. No membranes, no cell walls, no nothing. They don’t even code for proteins — they’re just themselves, the epitome of “simple”. Viroids are out there. And they’re lovin’ every minute of it.

Of course, living simple has some downsides. So far as we know, no viroids have Twitter accounts, for instance. Also, they can’t reproduce by themselves — we’ve all been there, amirite? — but need to infect a living cell to “borrow” its machinery to make more copies of its RNA. Most of those living cells are in plants; viroids have been identified that infect potatoes, eggplants, avocados and coconuts, among others.

Because they can’t reproduce by themselves — or in ugly-RNA-bumping pairs — viroids aren’t considered to be “alive”, exactly. But they may provide a hint as to how life ultimately began on the planet. Making copies of oneself — with help, and before one really has a “self” to speak of — isn’t much, perhaps. But it’s an important step on the way to truly living, and might have been critical to the formation of the very earliest life forms.

And today, viroids can still float around a farm field, dig into crops and pass along their genetic material to new generations. From what I’ve seen of the “simplify” crowd, most of those people would love the viroid lifestyle. Or near-lifestyle, as the case may be.

Of course, that “lifestyle” also involves running around naked, mooching other peoples’ equipment and using vegetables for sex.

I’m not saying that would deter any of the hippies pining for a life change. But suddenly, viroids don’t sound so “simple” to me.

Also, that Netflix queue of mine isn’t going to watch itself. I’ll pass.

Actual Science:
Virology BlogViroids, infectious agents that encode no proteins
Small Things ConsideredSmallest Things Considered
New York TimesA tiny emissary from the ancient past
Science Magazine / OriginsFast-mutating viroids hold clues to early life
Washington State UniversityHop stunt viroid research

Image sources: Nature Reviews (viroid structure), Neptune Society (kids with signs), QuickMeme (Kramer, LOVIN’ it!), The Snipe (sexy, sexy eggplant)

· Write a comment
· Tags: , , , , , , , , ,

· Categories: Biology
What I’ve Learned:

DNA polymerase: come with me if you want to replicate.
“DNA polymerase: come with me if you want to replicate.”

DNA polymerase is an enzyme present in every living cell. Hay cells, jay cells, even George Takei cells. Oh, my.

In these cells, DNA polymerase has one job — just one job — and it’s both the easiest and hardest job on Earth. Biology textbooks would tell you that job is to “replicate” the cell’s genetic material, reading and copying DNA so when the cell splits, both new cells contain a full set of genes.

And that’s true, in the same way it’s true that Tito Jackson recorded twenty Jackson 5 records. He did — but he had a hell of a lot of help.

It’s the same with DNA polymerase. It plays an important role in replicating DNA, sure, but it’s led to the job site by an entourage of support proteins, propped into place, and prompted for its lines. Each bit (or “base”) of DNA to be copied is a cue, and it’s DNA polymerase’s job to add the right complementary base in response. There are four different kinds of bases, so it only has four lines to remember.

This is why DNA polymerase’s job is the easiest in the world. It’s treated like a star. It gets driven to the set, carried to the stage, and it barely has to study a script. It just reads a cue and delivers the right line, out of four choices. It’s the gig of a lifetime.

Actually, I imagine it’s a lot like Arnold Schwarzenegger’s life these days. He probably does the odd public appearance for pocket change, followed around by a gaggle of handlers. They’d behave like the DNA replication helpers — getting him to the podium, making his hair look nice and prompting him for the appropriate line:

If it’s a Terminator convention, he’ll say: “I’ll be back!

At a children’s event: “It’s not a tumah!

At a GOP fundraiser: “I’m the Governator!

For a crowd of Predator fans worried about Anna: “Get to da choppa!

So wherever he goes, a flunky whispers into his ear: “Terminator”, “children”, “GOP” or “Anna”. And Arnold gives the proper response.

(Maybe the flunky even shortens it to one-letter codes: T, C, G and A.

Aw, yeah. You biochemical geneticists see what I did there.)

So DNA polymerase’s job is simple — as easy as a T-800 following a four-path if-then logic loop. Which is to say, it’s easy to do once. Even a few times a week, a la the former-Governator.

But there’s the rub. Human DNA polymerase reads and matches a DNA base about fifty times per second.

(E. coli polymerase is even faster, around one thousand matches per second. If you can picture a bacterial Arnold Schwarzenegger, moving at twenty times the speed. Hasta la nightmare, baby.)

That’s why DNA polymerase has the hardest job in the world. Our genomes are three billion bases long, and in rapidly-dividing cells like skin or hair or stomach lining, the replication never stops. One mismatch could create a mutation that kills the cell, or cause out-of-control growth into cancer. (“Then it IS a tumah!”) Yet our DNA polymerases are extremely accurate, mismatching less than once every ten million bases — and they can even correct their occasional mistakes.

Which is good news for us. It’s no big deal if an aging actor accidentally tells a bunch of six-year-olds to “get to da choppa!“. But our inner Ahhhnolds get their lines right — all the time, nearly every time, and without the help of cue cards. That’s why if it bleeds… we can find DNA polymerase inside it.

Actual Science:
How Stuff WorksDNA replication
The OncologistThe molecular perspective: DNA polymerase
WileyDNA replication
Asian ScientistDemystifying Rule-Defying DNA Polymerases

Image sources: Vanderbilt University (DNA replication), Fanpop / Michael Jackson (Jackson 5), Screening Notes (“Tumah!”), New England Biolabs and TalkBacker (polymerase T-800)

· Write a comment
· Tags: , , , , , , , , , ,