Moss That Swings Both (All?) Ways

by Jennifer Frazer on May 23, 2009

I’m sometimes greatly amused by the quality of press release science writing that is taking the place of professional science writing these days, since no one will pay for us to do it full time anymore (Science Daily, a major source of  internet science news, is made almost entirely of press releases reprinted verbatim. And you’ll notice that this very blog is, so far, gratis).

For instance, a press release on one of the coolest things I’ve seen in a long time includes this sentence, seemingly lifted from Timmy’s 3rd grade report on mosses:

At first glance, mosses and human beings have little in common.

Gee, ya think? I’m imagining myself at a coffee shop holding a cup of steaming tea and sitting across the table from a noticeably uncomfortable bryophyte.

Cough. *Blink*

Cough. *Blink*

Me: So, read anything interesting lately?

Moss: No.

See? Not much in common. Strangely, this doesn’t differ greatly from most of my actual dates.

I don’t want to seem too hard on the author here, since 1. the release was probably first written in German, and 2. this is actually one of the clearer and more helpful press releases I’ve read. In any case . . .

Scientists from ETH Zurich and the University of Freiburg im Breisgau report that they were able to insert DNA from humans and bacteria into the moss Physcomitrella patens (sounds suspiciously close to “patent”) and the moss was able to manufacture human proteins without any further help. Yes, they basically cut and paste. And the moss said: OK! Cool!

The protonema of Physcomitrella patens. When the spore of this moss lands on a suitable spot, it starts growing into filaments like these. You can see the chloroplasts, or light harvesting equipent, as little green circles.

The protonema of Physcomitrella patens. When the spore of this moss lands on a suitable spot, it starts growing into filaments like these. Given enough time, these little filaments will grow into a full-grown moss plant. You can see the chloroplasts, or light harvesting equipment, as little green circles.

For those of you unfamiliar with the Way of the Cell, DNA makes RNA (with the help of proteins called RNA polymerases), and RNA makes proteins (with the help of cell organelles called ribosomes). The reason this moss-cular feat is astounding is that doing the same thing with flowering plants will get you nada. The mammalian gene start and end sequences have evolved themselves right out of business when placed in a similarly much-modified flowering plant. Not that there’s much of a reason that that would *ever* happen in nature. Now in an evil mad plant scientist laboratory, on the other hand . . . Belgians + petunias = Brussels sprouts. Mwa ha ha ha ha ha . . . . .

How is it mosses can do what so-called “higher” plants cannot? It’s a mistake to think of mosses as “primitive” in the sense of “inferior”. Both mosses and flowering plants have ancestors that were alive at the same time. What mosses are is “less-derived”, in biologist-speak. The lineage that gave us mosses just didn’t change as much over time as the lineage that produced flowering plants, because they found they were well-adapted as-is to their particular niche (forests, rocks, sidewalk cracks, and the sets of “Lord of the Rings” adaptations). Like sharks, they found a sweet gig and they stuck with it.

According to Ralf Reski, botanist and co-author of the paper announcing this discovery, as part of this cozying into a niche relatively early on for multicellular life (moss seem to have sprouted out of the ocean and then pretty much called it a day) mosses have stayed genetic generalists. And this easy-going gene-set enables them to translate a wide range of DNA. In fact, hold on to your hats . . .

This cross-kingdom conservation of mammalian and moss protein production machineries is phylogenetically profound, and has several implications for basic and applied research. Comparative genomics, as well as functional studies, have recently established major differences in metabolic pathways and gene function between flowering plants and P. patens, and have suggested that a substantial moss gene pool is more closely related to mammals than to flowering plants (Frank et al., 2007; Rensing et al., 2008).

—Plant Biotechnology Journal, Volume 7, Issue 1, 2009. Pages: 73–86

Dude! An article in the Plant Biotechnology Journal just blew my mind!

Who knew? Well, maybe John Wyndham.

In my next post, we’ll take a look at what on Earth possessed these scientists to stuff human genes into a soft, green, cushiony object and at why biology is WAY cooler than nuclear physics. Stay tuned.

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What You See When You Drink Too Much in Thailand

by Jennifer Frazer on May 20, 2009

This is what you see when you drink too much in Thailand.

I love the smell of cyanide in the morning. Smells like . . . Desmoxytes.

Because nothing says, “Don’t Eat Me!” quite like a neon pink millipede (unless you’re two, in which case it says, “All You Can Eat Candy Buffet!”), I give you: The Pink Cyanide Millipede.

In addition to its easily pronounceable Thai (Mangkorn chomphoo) and Latin (Desmoxytes purpurosea) names, it features a pleasing almond aroma (courtesy of the cyanide it’s oozing).  Pink millipede saté sticks, anyone?

To see more bizarre animals either discovered or more fully investigated in the last few years (including our old friend the barreleye fish and the can’t-miss flesh-eating ghost slug), check out this gallery of bizarre animals over at New Scientist. You’ll be glad you did!

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Ancient Egypt lives on — thanks to Trixie and Ralph

by Jennifer Frazer on May 16, 2009

Though cattle wouldn’t ordinarily grace the pages of The Artful Amoeba (vertebrates in general being a bit boring for my taste), I make an exception today. In the Denver Post was an article about the birth of a new ankole calf named Belle at the Denver Zoo to proud parents Trixie and Ralph (yes, of Honeymooners fame).

Take a look.

Awwwwwwww . . . . .  but as a female mammal, I must say Thank God the little darlings are born SANS horns. *Shudder*.

The breed is also called Egyptian longhorn, but before I even got to this detail in the article, I was struck by how closely these cattle resemble the cattle Egyptians actually depicted in and on their tombs:

Photo by Gérard Ducher, distributed under a Creative Commons attribution license. Click image for link.

Photo by Gérard Ducher, distributed under a Creative Commons attribution license. Click image for link.

The cow second from left looks a lot like Belle. This model is from an incredible collection found in the the Middle Egyptian tomb of a noble called Meketre who died ca. 2000 B.C. In his tomb in a secret room that tomb robbers missed were found intricate dollhouse-like models of soldiers marching, sailors rowing, brewers brewing, bakers baking, or Meketre himself counting his cattle. Meketre had all these models placed in his tomb so all these things could happen for him in the next world. Together, they form an intimate, detailed snapshot of daily life in ancient Egypt. If you’re ever at the Met in New York City, don’t miss their share of the collection.

Here’s the nobleman Sennedjem with Egyptian cattle as seen on his tomb wall:

The artisan Sennedjem plows heavenly fields on his tomb wall. Ca. reign of Seti I/Ramesses II.

The artisan Sennedjem plows heavenly fields on his tomb wall. Ca. reign of Seti I/Ramesses II, 1200s B.C.

I’ve always loved those splotchy cattle with the big horns I see in Egyptian art. It’s nice to know that even though the builders of the pyramids and their culture are long gone, their cattle, at least, live on.

And while we’re on the subject of animals in Egyptian art, I’ve also been struck by the contrast between the formal, stiff poses Egyptian artists used to depict humans, and the Audubon-esque naturalism with which they sometimes precociously depicted animals. They had a keen eye for detail, as you can see in this painting of geese made almost 5,000 years ago during the Old Kingdom.

Geese depicted on the tomb of Nefermaat and his wife Atet during the reign of the triple-pyramid builder (and Ladies' Man) Snefru, ca. 2600 B.C.

Geese painted in the tomb of Nefermaat and his wife Atet during the reign of the triple-pyramid building Pharaoh (and Ladies' Man) Snefru, ca. 2600 B.C.

Just for the record, this panel of geese (not all are shown here) may be my favorite work of Egyptian art ever. Its simplicity, attention to detail, balance — and may I say grace? — are timeless. As far as I know, no other culture came close to this level of artistic excellence and realism for several thousand years (though hard to know, since most ancient art has gone way of dodo). This was a first for the world. And, one might also argue, for scientific illustration.

Hope you enjoyed a little art history and Egyptology with your biology. We’ll be back to our regularly scheduled programming tomorrow.

Jen

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Unidentified feathery object (UFO)

by Jennifer Frazer on May 10, 2009

Again via Deep Sea News, here’s a video of a “ninja seaweed” from the Red Sea. Prepare to be impressed:
ninja_of_seaweed

This is what 600 million years of relentless predation will do for ya, folks.

Nothing to see here. These aren’t the . . . whatevers . . . we’re looking for. Move along.

Guesses on the identity of this bad boy over at DSN ranged from some sort of cnidarian (like a soft coral or anemone) to a sea cucumber or even some sort of fancy sea turtle extra-option package. Your guess is as good as mine. Anyone here want to take a (groan) poke?

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New post tomorrow

by Jennifer Frazer on May 9, 2009

Hi everyone. Sorry it’s been a while between posts but almost all of my free time this week was taken up by preparing for a talk on lichens to some local schoolgirls on Thursday and a presentation I’m giving today at the Denver Skepticamp called “Life on Earth: The Short, Short Version.” Hang in there! I’ll be back soon.

jf

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Lesbian Necrophiliac Bdelloid Rotifers (and the Scientists who Love Them): Part 2

by Jennifer Frazer on May 5, 2009

So what is a bdelloid rotifer anyway? As you can see from the photomicrographs in the previous post, they are not going to be trying out for the Flyers anytime soon. Rotifers are among the simplest, smallest animals. In less than half a millimeter they pack in about a thousand cells, including a primitive nervous system (we’re talking like 15 cells here. “Rotifer-brained”: for times when “bird-brained” just doesn’t cut it), digestive system, and foot with — incredibly — toes.

Let’s put it this way: rotifers are multicellular animals that are smaller than some ciliated protists (protists include this blog’s titular amoebae and other high school biology favorites like Paramecium). They’re called bdelloid because they inch along like a leech — yes, bdelloid apparently means leech-like, as in, “Attack of the Giant Bdelloids.” Just doesn’t quite have the same ring to it as this.

They’re called rotifers (Latin: wheel-bearers) because they have a crown of little beating hairs called cilia surrounding their head that they use to suck in food — suspended organic particles, protists, or other small animals. Even more impressively, some rotifers have a toothed organ inside their mouth called the mastax that they use to grind food, and which they can actually sometimes evert to snare dinner.

An artist's interpretation of mastax eversion by a bdelloid rotifer. Any resemblance to Ridley Scott films is purely coincidental. Original image by rkitko, available under a Creative Commons Atribution license. Click image for link.

Rotifers have resurrectional powers rarely matched on Earth. After the typically fatal DNA- and membrane-shredding treatment incurred by drying up, they can somehow, once wetted, mend hundreds of DNA breaks and simply swim off. Even more jaw-droppingly, they can apparently use those same powers to withstand searing doses of radiation:

A comparison: in the most resistant arthropod[ed. note: arthropods include animals with jointed exoskeletons like insects and crustaceans] known, a 200 Gy dose produces more than 99% sterility; in bdelloids, a 560 Gy dose causing approximately 500 double-strand breaks per genome reduces fecundity by only 20%. The researchers point out that resistance to ionizing radiation may be an accidental by-product of resistance to desiccation. Both factors cause double-strand DNA breakage.

Forget balls of steel. This is DNA of steel. Why are we thinking of sending humans to Mars? Clearly, we should be sending bdelloid rotifers, who can thrive in the radiation-soaked environment of space, attack the Martians, and do it all backwards, in a high heel, and without breaking a chromosome.

In any case, you may be wondering where the lesbian necrophilia comes in. I’ll let the scientist at Harvard who studies these things  — Matthew Meselson — speak for himself.

It’s likely, he says, that during recovery from dessication, bdelloids pick up genes from members of their own species, too—dead members, that is, whose genes spill out of ruptured cell membranes. That process would provide the kind of genetic reshuffling that other animals achieve through sexual reproduction.

“It may be their form of sex,” Meselson says. “But their partner is essentially dead. So you’d have to call it necrophilia. Actually, since they’re all females, lesbian necrophilia.”

Kudos to you, sir, for being a scientist and not speaking like a grant application. If more scientists spoke this way, we might have less of a problem with people not giving a d— about science.

Much additional bio geek goodness can be found over at Small Things Considered.

(Additional source: Purves, Orians and Heller. Life: The Science of Biology. 4th ed.)

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Lesbian Necrophiliac Bdelloid Rotifers (and the Scientists who Love Them): Part 1

by Jennifer Frazer on April 30, 2009

So you’ve been having a rough decade eking out a living as a bdelloid rotifer, living in the soil, some moss, or a small vernal pool. First, it stopped raining a few days after you hatched. Then you entered a period of dried-up stasis in which your cell membranes ruptured, metabolism ground to a halt, and DNA may have been cuisinarted. Bummer.

But lucky for you, it started raining! And guess what, it’s raining genes! (Cue The Weather Girls) Which is great news, because your species is all female and hasn’t had sex in 100 million years. Hallelujah!

Scanning electron micrographs showing morphological variation of bdelloid rotifers and their jaws. We're going to need a bigger microscope (apologies to Roy Scheider and Peter Benchley). Photo by Diego Fontaneto, available under a Creative Commons Attribution license. Click photo for link.

As described in this little article over at discovermagazine.com, without a way to exchange and recombine genetic information, many animal species tend to degenerate and disappear over time (thus the joy of sex) because they lack efficient ways to generate novelty that can help them adapt to changing environments. That’s OK — when you’re a bdelloid rotifer, you can do it Hoover style: just vacuum up whatever stray DNA happens to be in your environment, including the genes of whatever it was you might have recently had for dinner (note to self: glad am not bdelloid rotifer). Plants, animals, bacteria, fungi, and who knows? — you might even get lucky. You might manage to incorporate some variant versions of your own species’s genes, thus escaping the cruel grind of creeping genetic obsolescence.

Coming soon: Part 2: So what is a bdelloid rotifer anyway?

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The Fish with the Observation Deck

by Jennifer Frazer on April 22, 2009

Back in March, I posted a link on Facebook to this blog, the aptly named, “Scientists Solve the Mystery of Why this Fish is So Freakin’ Crazy”, at the Deep Sea News.

The blog includes this clip:

If there was ever a fish that belonged on Futurama . . . this is it. The see-through head apparently protects the fish’s eyes from the stinging sea creatures it steals its food from. I knew there was a reason I keep a pair of safety goggles in my kitchen; you never know when the soup will shoot a nematocyst-covered stinging tentacle your way . . . see Better Off Dead.

But then on Monday, DSN posted a new link to — amazingly — a Colbert Report clip about the fish. Just so you know, Colbert’s reaction is pretty much how I feel about all the crazy organisms I’ll be writing about on this blog. To wit:

The Colbert Report Mon – Thurs 11:30pm / 10:30c
Craziest F#?king Thing I’ve Ever Heard – Barreleye Fish
colbertnation.com
Colbert Report Full Episodes Political Humor NASA Name Contest

If this clip won’t load, you can find the DSN version here.

Oh, and just for the record, the fish’s latin name, Macropinna microstoma, roughly translates to “Big wing little mouth”.

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My science lineage on NPR!

by Jennifer Frazer on April 15, 2009

So most of my friends (and probably most of you here) have figured out I’m a bit, well, extra excited about fungi. Well, the person who planted the spore in my brain (and the person who trained her) hit the airwaves and Interwebz today after Cornell (Alma mater A) published a press release about the return of some rare Chinese fungi to their home.

Here and here are print versions of the story, and here is a version that aired on NPR today (thank you Kathie and Daniel for the links!).

Kathie Hodge, the Cornell herbarium’s director, said the fungi are invariably tiny — “just dried up leaves, most of them, or pieces of wood with a little dot on them. To an average person, they look like something you would sweep off your kitchen floor. But under the microscope they’re beautiful and exciting and incredibly diverse.”

“I think it’s really important to understand the diversity of life on Earth and we are so far from being able to do that right now,” she said. “And fungi are one of the last great frontiers of biology.”

These rare fungi just made it out of Dodge before the Japanese played havoc with the country during the Sino-Japanese war prior to World War II, and the stories imply had it not been for the heroic efforts of a Chinese Cornell alum to sneak them out of the country and ship them to Ithaca, they would all have been lost. Instead, they headed to Cornell where they met a fate similar to the Ark of the Covenant at the end of Raiders of the Lost Ark: warehousing in the Cornell Plant Path Herbarium (I don’t mean to imply that’s a bad thing — quite the contrary! Although I did once visit the Herbarium, and I have to say, it was very mothbally).

The story of what happened to their valiant rescuer is sad, though, and a testament to the brutality of the Cultural Revolution. I’ve seen several movies that portrayed it, at least in part, including The Red Violin and Farewell My Concubine. I never cease to be appalled.

Here’s hoping the current Chinese government can put these specimens to good use (though if you read carefully, you see we are keeping half of each sample just to be on the safe side). Lord knows the ecology of China is not what it once was. It occurs to me that these specimens provide the hope that if some have gone extinct, we might at least be able to perform the Jurassic Park treatment.

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Thwarting "Beaver Fever"

by Jennifer Frazer on March 30, 2009

I give you . . . Giardia.

In spite of what you're thinking, this is not the love child of a squid and a kernel of corn.

In spite of what you're thinking, this is not the love child of a squid and a kernel of corn.

Also known as *cough* beaver fever (since the dam rodents are common carriers) to those hikers unlucky enough to have a run-in with this extremely unpleasant organism. Symptoms include such pleasantries as “projectile vomiting” and “explosive diarrhea”. Fortunately, I do not speak from personal experience.

This baby is the primary reason that all you outdoorspeople have to bother with bulky or foul-tasting water decontamination apparati. Unfortunately, it’s more than just annoying to people in countries with raw sewage washing down the street, who would probably gladly bother with bulky or foul-tasting water decontamination apparati if they could afford it.

So an article in the New York Times last week described a fascinating new vaccine strategy for defeating this and many protozoan parasites that rely on “coat switching”. Giardia has about 190 coat protein genes. It only needs one to function. Normally, it cycles through them one at a time about every 10 generations, yanking the rug out from your immune system each time. Someone had the bright idea to make the organism express them all at once, vastly condensing the time required for your immune system to learn them all from several lifetimes to several weeks.

Neat!

http://www.nytimes.com/2008/12/16/science/16giar.html

Its coat protein selection system is a prime example of how evolution has produced plenty of inefficiencies and life is not “perfect” (as if we needed a reminder). Instead of selecting one of its coat protein genes and only transcribing that, it transcribes *all* of them, and destroys all but the one it wants. Kinda like making dinner by cooking every recipe in the cookbook, and then tossing all the dishes but the one you’re actually having. And that’s not the only weird redundancy, according to the article. Giardia has two nuclei. No one knows why.

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