Ribosomes, the meaning of life

The purpose of life is for ribosomes to make more ribosomes, said my college biochemistry professor, and later friend, Harry Noller.

The award of the Nobel prize in chemistry for the structure of the ribosome gives me a happy excuse to describe the wonderousness of this molecular machine. The central dogma, the genetic code, and the ribosome itself inspire a fountain of awe within me. These are proof that understanding the mechanisms behind the beauty we see in the world gives our experiences more depth, not less as some people fear.

Ribosomes are found in all cells. You may remember them from high school biology, like I do: a bunch of tiny dots under the light microscope. This coarse view belies their complexity. Even bacterial ribosomes have 3 RNA molecules and over 50 proteins. They are made from two parts that assemble together around a messenger RNA. Ribosomes travel along the mRNA, decode the message, and make a specific strand of protein denoted by the genome.

All cellular life has ribosomes. That means that the last common ancestor that gave rise to all life that we have ever observed on this planet used ribosomes. And no wonder, since they make the enzymes that fulfill all life processes.

DNA->RNA->proteins. James Watson named this chemical flow of information the Central Dogma of life. Genes coded by in DNA are transcribed into its chemical sister RNA. The DNA stays in the nucleus, a couch potato, while the messenger RNA goes out into the cell to communicate the genes’ information. The messenger RNA ends up at ribosomes, which decode the messages and construct proteins following the instructions in the mRNA. These proteins are often enzymes, the cellular workers.

The DNA->RNA->Protein flow is so elegant, and yet contains an intriguing paradox. DNA requires proteins for its replication and maintenance. So how did this system come to be? A classic chicken and the egg problem: which came first, DNA or proteins? This is one of the deepest puzzles of the origins of life.

Perhaps, some scientists wonder, at one time this was an RNA World. Because RNA does DNA’s job of holding information in some viruses and because it performs some enzymatic tasks, like proteins, perhaps there was a time–a time way back before the last common ancestor–when all these tasks were accomplished by RNA. Then DNA, which is more stable, took over the information storage and proteins, which are more chemically diverse, took over the enzymatic functions.

When Harry Noller’s lab at UC Santa Cruz realized their experiments suggested the RNA was at the heart of the ribosome’s activity, some scientists just couldn’t believe it. Such a complex reaction! Proteins must be doing it! But, as biochemical and structural experiments have now proven, the ribosome is at its core a ribozyme. A ribozyme with dozens of protein helpers, that is. This is one of the reasons why getting the molecular structure of the ribosome was such a big deal and why (my former PhD thesis committee member) Tom Steitz is now a Nobel laureate.

What is still unknown is whether the ribosome is a remnant of an ancient all-RNA cell. I like to imagine it is. I envision a very simple cell where RNA is the genetic material. It replicates itself and it makes small protein chains to help out. Other people have the same notion and some are trying to create such a cell in the lab, like another 2009 Nobel laureate - Jack Szostak.

Oh, shoot. I haven’t quite gotten around to mentioning the amazing and mind-boggling nature of the genetic code. That will have to wait for another time.

This is Science

… where I introduce some Bay Area people spreading the Good Word about science.

On June 18, I attended a retreat for Bay Area science communicators. Attending were wonderful people from science museums and laboratories and schools, but the presence of some people who are also finding creative ways to educate adults about science surprised and delighted me. Here are a few of them.

Brian Malow, Science Comedian

making you *want* to understand the science to get the joke

making you *want* to understand the science to get the joke

Brian Malow is the science comedian. He is very funny. But you have to get the science to get the jokes. He says he gets very different reactions from different audiences. As you can imagine, the same joke that makes he American Chemical Society ROTFL can hear silence at a local bar.

I think: Finally! After years of not ‘getting’ popular culture jokes that send my peers into spasms of hilarity, I am of the ‘in’ group. (A nerd in the know!) But I think the promise of Brian’s craft goes way beyond this turning of tables. He’s making steps towards curing a problem that has long troubled me. I’ve often noticed that educated adults are expected to know certain things. We are expected to know who painted The Scream and how Portia relates to Shylock and what caused World War II. However, from quiz shows to dinner conversation, science topics are generally only referred to by their most well-known catch-terms or in the singular vein of the history of science. That’s not right. Science should be everywhere. It is everywhere. Adults should be expected to understand principles of science. And, if our society did expected that, I think they would.

Back to Brian: his science comedy expects and encourages people to know basic science, like mercury is hotter than Earth or that our universe has rules that govern things like matter and light. Scientists and skeptics and rational people aren’t stuffy. We can laugh. And having Brian Malow creating humorous material encourages everyone to come laugh with us.

You can find Brian here: http://www.sciencecomedian.com/ You can watch Brian in action here: http://www.youtube.com/sciencecomedian

Dr. Kiki, This Week in Science radio show host

current science chat radio

current science chat radio

Kristin Sanford, AKA Dr. Kiki, co-hosts a weekly radio show called This Week in Science. Each week she and her co-host Justin Jackson cover stories from the week’s science news that happen to catch their attention. They chat about the findings like grad students in the lunch room. Sometimes they are intrigued and sometimes a little dubious, but they always add a personal element of why the science in interesting. It’s almost as if they are adding back what the impersonal, starched format of scientific publications takes away.

You can listen to the show live from 8:30 to 9:30 am Pacific Time or subscribe to the podcast. http://www.twis.org/

Kishore Hari, Bay Area Science and Science Cafes

bring science to thte people (in bars)

bringing science to the people (in bars)

There was a time when science lectures were considered prime entertainment. Kishore Hari is bringing that era back. Kishore organizes the Down to a Science science cafes, which allow people to enjoy the wonders of science with a drink in their hands. (The best way, I think!) Kishore invites scientists from the local laboratories and universities to give a short, general talk and participate in an extended Q&A about their research. The talks are geared toward the general public and promise to not be stuffy. The events are free and convene at various neighborhood bars.

Kishore’s science cafes are here: http://www.sciencecafesf.com/ You can find a very useful listing of science events in the Bay Area here: http://www.bayareascience.org/ Also, if you live in the Bay Area, you must follow him on Twitter: http://twitter.com/bayareascience/

A Science Solstice?

Every child is naturally curious about the world. Children explore, chase insects, and question the whys of Nature. Upon growing up, this innate wonder can dull. Be it through weighty responsibilities, boredom, or changes in priorities, adults can forget the joy possible from observing Nature and grappling with its puzzles.

I propose an annual holiday that encourages us to remember and nurture our curiosity about the world and to appreciate what a mystifyingly wonderful thing it is to be alive on an Earth full of beautiful, strange, and diverse life in a Universe of laws and incomprehension.

Summer solstice is the perfect date for such a holiday because it has physical meaning to Nature. It isn’t an arbitrary date; it is the day of the most northern sunrise, the longest day of the year. Not only does this remind us that we live on a planet, but it gives us plenty of daylight to enjoy and explore.

Some Science Solstice celebration suggestions:

  • take a nature walk, bring plant and animal identification guides
  • have a sciency song sing-along, like Monte Python’s “Galaxy” and They Might Be Giant’s sun song
  • spend a least an hour staring at the clouds
  • bake bread, thank the yeast
  • mixology experiment: layer drinks of different densities
  • pull out the binoculars, pull out the telescope
  • watch ants
  • be thankful we live on a planet with a tilt and this seasons
  • contemplate the molten magma beneath your feet
  • eat foods that are grown locally and in season
  • swap fun science factinis with friends

I believe a holiday encouragng the observance and contemplation of nature encourages spiritual growth as much as (well, OK - I think prbably more than) the traditional religious holidays. What an amazingly magical Universe we live in!

Dopamine Day

For a few years I’ve intermittently campaigned for the renaming of Valentines Day to Dopamine Day. After all, that’s what it’s really about. The thrill of romantic love is largely the handiwork of the neurotransmitter dopamine.

We would celebrate Dopamine Day by engaging in activities that increase dopamine, like savoring chocolates, giving and receiving gifts, enjoying a nice meal, catching a show, and being close to your lover. Sound familiar? That’s probably because Valentines Day already is Dopamine Day but under a less specific, or at least less alliterative, name.

Dopamine Day encompasses so much more, though. It doesn’t leave single people out in the cold, like Valentines Day does. Don’t have a lover? That’s not a problem for Dopamine Day! Your potential for enjoying dopamine isn’t dependent on your relationship status. The trick for releasing dopamine is to try something novel and thrilling, like exploring a new city or skydiving or rafting. Not very adventurous? Then engaging in fantasy, like a movie or a book may be more your style. The addition of chocolate never hurts.

It seems appropriate to interject here with a pertinent factini. The brains of people who are in the crazy-in-love stage of love look like the brains of people who are high on cocaine. Now, I’m not suggesting you celebrate Dopamine Day by snorting coke; that’s too easy - and therefore dangerous. (In fact one could argue whether or not celebrating Dopamine Day with someone you are madly in love with “too easy.” I’ll let that debate slide for now.)

To really give dopamine its awe-inspiring due, it’s important to note that cocaine and other drugs are addictive because they hijack the dopamine pleasure/reward system. Dopamine feels *that good* and its pull is *that irresistible*.

So, let’s celebrate the goodness and irresistibly of dopamine, without which we would lose our zest for much of life. In fact, without dopamine to pull us in the direction of maintaining our necessary life functions, I doubt we could exist. We would certainly not be human.

I plan to celebrate Dopamine Day with a wander in the redwoods, an indulgence in a novel, and plenty of chocolate & zinfandel. Maybe I’ll surprise people with little Dopamine Day cards, too. That will help spread the love!

Hooray for dopamine!

Kissing decreases cortisol and increases oxytocin

Today’s factini isn’t so surprising. Kissing makes us feel less stress (lower cortisol) and more bonded (higher oxytocin), reports psychologist Wendy Hill of Lafayette College. What is interesting: while kissing causes a cortisol decrease in both men and women, oxytocin is increased more in men than in women. The researchers assume that this has to do with environment. Women need a certain atmosphere.

The hormonal changes due to kissing may have to do with pheromones exchanged in saliva, but -for maximum efficacy - I wouldn’t recommend thinking about this during the act.

The Telegraph article states:

In 2007 British scientists measured the brain and heart activity sparked by passionate kissing, but found it was less intense that the stimulation produced by eating chocolate.

Uh-huh! That’s why this Dopamine Day, I have a date with some fine chocolate. I can’t wait to touch my lips to that sweet catch!

Neurotransmitter Personality Type

Helen Fisher rocks. And not just because she is willing to put love, a societal sacred cow, under her anthropologist’s cutting knife, but because she got science into Oprah’s O Magazine.

It’s old news to avid O readers, but new news to me that Fisher wrote an article in 2007 called What’s Your Love Type? for O. While a lot of this article reads like your typical magazine personality test, it strays from the herd by relating each of four personality types to a neurotransmitter. Roughly, it is:

Dopamine - someone with a powerful dopamine system will seek out novelty = adventurer

Estrogen - estrogen allows empathy and emotional intelligence (I wonder if there’s some oxytocin in there, too.) = negotiator

Serotonin - a lot of serotonin makes people even-keeled, loyal, and structured = builder

Testosterone - drive and rationality = director

Admittedly such categorizations are simplistic have limited use for the well-rounded. But, since I like to think about the actions of neurotransmitters on my mood and emotions, I like this chart. I especially like that Fisher found her categories largely matched with those made by psychologists, like the Jungian Myers-Briggs test. Of course, there’s a bit of a chicken-and-egg problem, or more of a looking at the quark problem. Are these archetypes  ubiquitous because they permeate the mythology of our culture or are they part of our cultural mythologies because they have a biological origin?

But, back to my point: science in O Magazine! Neurotransmitters were mentioned, and I think that counts. Right on, Helen Fisher!

Listen to this interview for a great quote:

Leonard Lopate:

“A scientific approach does take some of the romance out of the question, doesn’t it?”

Helen Fisher:

“Well, not for me. You can know every single chemical in a piece of chocolate cake and still sit down and eat the cake and be thrilled. Ad you can know every single part of an enginine of a Farari and get into the machine and drive it and enjoy the road. So for me it’s added a tramendous depth and breadth and highth to it.”

(Sound like Richard Feynman’s flower quote?)

Helen Fisher’s website

Hey Baby, what’s your AVPR1A like?

oxytocin, the superglue of neurotransmitters

oxytocin, the superglue of neurotransmitters

I recently heard about a friend of a friend of a friend hosting an oxytocin-sniffing party. I don’t know how common or rare that is, but it was new to me. I was immediately intrigued: I would love to know what the direct effects of oxytocin feel like. I mean, I *think* I know, but how fun to know for sure! Then my wiser friend cautioned that this may be more dangerous than fun.

He’s right. When female prairie voles’ brains are injected with oxytocin (usually what happens during mating), they pair-mate with the closest male, not their favorite and not the most evolutionary fit - the closest. Ewes injected with oxytocin bond to an unknown lamb like it is her own. People sniffing oxytocin are more likely to trust strangers while playing a gambling game, whether the strangers deserve it or not. Oxytocin is the superglue of neurotransmitters - care must be taken so you don’t do something dumb like mistakenly bond your fingers together.

I don’t know if sniffing oxytocin at a party would cause me to become attached to someone with whom I normally would not want to spend much time. But, um, I don’t think I’ll take the chance.

Unfortunate bonding is not only a danger at mysterious parties of indulgence. It can happen in the sober real-world, too. How wonderful it would be to sever the oxytocin and dopamine ties to someone after a break-up. Those weeks or months of weight-loss, yearning, and aching - gone.

Larry J. Youngs’s essay in Nature last week suggests that we are on the path to do just that. Our unraveling of the biochemical pathways behind love and bonding may lead to a love potion or genetic counseling for relationships, since the vasopressin receptor gene AVPR1A is linked to pair bonding ability (read: propensity to cheat) in human males.

In a New York Times article responding to Young’s essay, John Tierney argues the practicality of a love vaccine. This isn’t science fiction - an oxytocin blocker does turn normally monogamous female voles into philandering playgirls. What having blocked oxytocin would actually feel like is hard to imagine. Would the females be enjoying that sex or would it feel emptier?

I find it helps just to know what’s going on with oxytocin and dopamine and vasopressin in the various stages of becoming and being in love. Being able to manipulate these molecules in the process, like a kit of various adhesives and solvents, well, that could take some practice and I’m sure some fingers would lose a bit of skin in the mastering.

Science Art Networking

Bob Nidever has recently created virtual spaces for science art networking.

His blog “Art in Science” lists science art competitions and opportunities: http://artinscience.wordpress.com/

His Facebook group “Science Art Cafe” for chatting and networking: http://www.facebook.com/group.php?gid=46717338652

His twitter: http://www.twitter.com/bnidever

I hope these take off - science art networking is so very needed.

Introducing: Factini

OK, at first glance the word may look silly. But it should suit my need.

Ever since finding out that using the word factoid for a true fact, rather than an almost-but-not-quite-true fact, is incorrect, I’ve hoped to find an appropriate substitute. I need a word for the little tidbits of scientific results I so love so. I love telling my mom about oxytocin and trust, my heartbroken friends about vassopressin and voles, and random strangers at cocktail parties about, gosh, anything I read in New Scientist that happens to fit into the conversation. Science Nerd, sure. But I have enough English Major in me to hesitate to knowingly misuse words.

So, after some deliberation, I decided “factini” would work well to mean a small fact - a real fact. Perhaps a fact that could be taken out of context a bit or taken a step beyond what is strictly proven, but the best factini inspires wonder and/or comprehension in a eureka flash.

And it’s best served dry with two olives.

Year of Science

The Coalition on the Public Understanding of Science (COPUS) has named 2009 the Year of Science. They have given each month of 2009 a theme - we will have to wait for November to celebrate chemistry. January’s theme is “the process and nature of science.”

I don’t really have much to say about this first theme. While it is certainly important for people to understand that science proposes testable theories, tests them, and revises its story in iterative fashion, I’d hate to think that focus on the process part might get in the way of sharing the wonderment-inspiring results part. I remember (without nostalgia) having to memorize the discrete steps of the scientific process in grade school. Did I follow these to the letter in my own research? Uh, of course not. So why make our third graders think science is about memorizing rather than exploring? I would have preferred the extra time to inoculate a few more petri dishes. Now *that* makes me nostalgic.

I noticed that the Year of Science agenda doesn’t include much science art, yet. I hope we can change that…

COPUS is a grassroots network of a variety of science research and education entities. Its mission is to increase public understanding of science. You can see all the monthly themes and a calendar of events on their website: http://www.yearofscience2009.org/

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