Saturday, September 12, 2009

Our Very Own Morimoto in the News!

A new Northwestern University study reports that protein damage can be detected much earlier than we had thought, long before individuals exhibit symptoms. But the study also suggests if we intervene early enough, the damage could be delayed.

In studying seven different proteins of the worm C. elegans, the researchers discovered that each protein misfolds at the same point: during early adulthood and long before the animal shows any behavioral, or physiological, change. (Each protein had a minor mutation that affects folding.)

The misfolding coincided with the loss of a critical protective cellular mechanism: the ability to activate the heat shock response, an ancient genetic switch that senses damaged proteins and protects cells by preventing protein misfolding.

The results will be published online during the week of Aug. 24 by the Proceedings of the National Academy of Sciences(PNAS).

"I didn't expect the results to be so dramatic, for these different proteins that vary in concentration and are expressed in diverse tissues to collapse at the same time," said lead researcher Richard I. Morimoto. "This suggests the animal's protective cellular stress response becomes deficient during aging."

Could the damaging events of protein misfolding be prevented or at least delayed?

To find out, the researchers gave the animals the equivalent of a vitamin, boosting the heat shock response early in the animal's development, prior to protein damage. Now, instead of misfolding around day four, the equivalent of early adulthood in the worm, the proteins didn't start misfolding until day 12. (Behavioral changes didn't appear for at least three days after misfolding. The average lifespan of the worm is 21 days.)

"Our data suggest that, in terms of therapeutics, you have to start early to prevent damage and keep cells healthy," said Morimoto, Bill and Gayle Cook Professor of Biochemistry, Molecular Biology and Cell Biology in Northwestern's Weinberg College of Arts and Sciences. "When you see a loss of function, it's too late."

Genes that regulate lifespan were first discovered in C. elegans. The transparent roundworm is a favorite organism of biologists because its biochemical environment and fundamental mechanisms are similar to that of human beings and its genome, or complete genetic sequence, is known.

The title of the PNAS paper is "Collapse of Proteostasis Represents an Early Molecular Event in C. elegans Aging." In addition to Morimoto, other authors of the paper are Anat Ben-Zvi and Elizabeth A. Miller, both from Northwestern.

Sunday, April 19, 2009

Study Shows Aspirin Blocks "Plant Pain"

This is an old article stolen directly from ScienceDaily, but I found it to be really friggin' cool:

ScienceDaily (Aug. 6, 1998) — It's not news anymore that plants may "cry in pain" when attacked or damaged by a hungry herbivore, but now we know that there is a way to stop all this vegetable "suffering" right in your medicine cabinet -- with simple aspirin.

Plants may not feel the pain of an injury as animals do, but they do have their own "alarm" reaction to tissue damage and, in an effect curiously similar to that in animals, this reaction can be short-circuited by aspirin and other similar drugs, according to a study recently published in The Journal of Biological Chemistry.

The study was authored by plant biologists Zhiqiang Pan of Arizona State University; Bilal Camara of the Institut de Biologie Moleculaire des Plantes, Strasbourg, France; Harold W. Gardner of the United States Department of Agriculture; and Ralph A. Backhaus of Arizona State University and appeared in JBC's July 17 issue.

Aspirin, the researchers discovered, interrupts the production of a key compound that plants produce in response to physical injury in much the same way that it interrupts in animals the production of the compound that tissue produces when it is hurt, leading to the pain reaction.

The function of aspirin in animals is to block the production of prostaglandin, which triggers swelling and pain. Aspirin binds to the active site of the enzyme that is critical to producing prostaglandin.

"It essentially renders the enzyme dead and prevents prostaglandins from building up and creating a reaction," said Backhaus.

In plants, aspirin blocks the production of jasmonic acid by similarly binding a critical enzyme.

"Jasmonic acid is a hormone that is made when plants are in distress. It signals the production of plant-defense compounds -- it works a little like a shot of pain, warning the plant that it is under attack. It can also volatilize and warn nearby plants, a chain reaction that's like a warning signal to other plants. This seems to particularly apply to insect attack, as the alerted plants then produce specific compounds that produce insect gastro-intestinal distress.

"It turns out that aspirin will suppress the formation of this compound (jasmonic acid), so it suppresses the warning signal, like it suppresses pain in animals," Backhaus said.

While humans may want to tune out the pain "alarm" signaling that their body is under distress, it is hard to see what benefit aspirin's suppression could have in the plant reaction.

Unless you're a hungry insect ransacking a patch of plants, that is, and you want to shut off the neighborhood's burglar alarms... and have lunch.

Sunday, March 15, 2009

How to Clean Out the Inside of a Peanut Butter Jar

I found myself in a sticky situation the other day. I was in full study mode and was hoping to steal some peanut butter from my dining hall. The problem: no container! Well, as it turned out, I did have a container, but it had a bunch of old, expired peanut butter and I didn't wanna risk making myself sick before my Orgo final. So, what'd I do? I poured a dab of laundry detergent into the peanut butter jar with some hot water and shook it. Then *poof*--no more peanut butter in the jar!

You'd might guess that it's simple enough: the detergent just cleaned the peanut butter of out the jar... in that case, you'd be right. But maybe you'd try to use soap. Soap would probably work too, but not as well. So, what's the difference? As it turns out, this is a biochem problem. As anybody who eats peanut butter knows, it is full of proteins. So, to clean out a peanut butter jar, simply break don't all those proteins--which detergent does quite well. Why? Well, the active ingredient in detergent isn't just a really tough soap; in fact, it contains a tiny but potent amount of proteases--enzymes that digest and break down proteins. So the proteases (which are also heat-resistant) break down the proteins, and the hot water washes 'em away.

Hence I am left with a clean peanut butter jar in a jiffy. With that, I am off to steal some peanut butter!

Sunday, January 11, 2009

Another Step Forward in the Fight Against Cancer

Harvard researchers have found a way to use a polymer cylindrical implant to reprogram immune cells to target cancer--90% of mice afflicted with melanoma were cured.