Featured Research

from universities, journals, and other organizations

'Mad Cow' Mechanism May Be Integral To Storing Memory

Date:
December 29, 2003
Source:
Whitehead Institute For Biomedical Research
Summary:
Scientists have discovered a new process for how memories might be stored, a finding that could help explain one of the least-understood activities of the brain. What's more, the key player in this process is a protein that acts just like a prion – a class of proteins that includes the deadly agents involved in neurodegenerative conditions such as mad cow disease.

CAMBRIDGE, Mass. (Dec. 24, 2003) – Scientists have discovered a new process for how memories might be stored, a finding that could help explain one of the least-understood activities of the brain. What's more, the key player in this process is a protein that acts just like a prion – a class of proteins that includes the deadly agents involved in neurodegenerative conditions such as mad cow disease.

The study, published as two papers in the Dec. 26 issue of the journal Cell, suggests that this protein does its good work while in a prion state, contradicting a widely held belief that a protein that has prion activity is toxic or at least doesn't function properly.

"For a while we've known quite a bit about how memory works, but we've had no clear concept of what the key storage device is," says Whitehead Institute for Biomedical Research Director Susan Lindquist, who coauthored the study with neurobiologist Eric Kandel at Columbia University. "This study suggests what the storage device might be – but it's such a surprising suggestion to find that a prion-like activity may be involved."

Central to a protein's function is its shape, and most proteins maintain only one shape throughout their lifetime. Prions, on the other hand, are proteins that can suddenly alter their shape, or misfold. But more than just misfolding themselves, they influence other proteins of the same type to do the same. In all known cases, the proteins in these misfolded clusters cease their normal function and either die or are deadly to the cell – and ultimately to the organism.

For this reason, Kausik Si, a postdoc in Kandel's lab, was surprised to find that a protein related to maintaining long-term memory contained certain distinct prion signatures. The protein, CPEB, resides in central-nervous-system synapses, the junctions that connect neurons in the brain. Memories are contained within that intricate network of approximately 1 trillion neurons and their synapses. With experience and learning, new junctions form and others are strengthened. CPEB synthesizes proteins that strengthen such synapses as memories are formed, enabling the synapses to retain those memories over long periods.

For the study, the team extracted the CPEB protein from a sea slug. This lowly creature has achieved high status in neurobiology because its neurons are so big, they can be manipulated and turned into unusually powerful investigative tools. The researchers fused this CPEB to other proteins that would serve as reporters of activity, and then observed its behavior in a variety of yeast models. The researchers discovered that CPEB altered its form and caused other proteins to follow – functioning exactly like a prion. A second unexpected finding was that CPEB carried out its normal function – protein synthesis – when it was in its prion state.

"This is remarkable not just because the protein executes a positive function in its prion-like state," says Lindquist. "It also indicates that prions aren't just oddballs of nature but might participate in fundamental processes."

The finding contradicts the notion that converting to a prion state is a bad thing, says Kandel. "We show instead that the normal state of CPEB may be the less active state, and the prion state may be the effective way of utilizing the normal function of the protein."

The work suggests it's possible that in mammalian neuronal synapses, CPEB's prion properties may be the mechanism that enables the synapses and nerve cells to store long-term memory, a theory the researchers plan to investigate next. Theoretically at least, prions are perfect for this, says Lindquist. Prions could shift into this state quickly without the energy-intensive cellular mechanics that fuel most protein synthesis. The prion state is very stable and can maintain itself for months, even years.

But, "We still need to demonstrate that this prion mechanism operates not just in yeast but in neuron cells," says Kandel.

Lindquist believes that these findings will not be the last time prions are discovered to have normal biological roles. In fact, she has long speculated that researchers will discover them to be essential to many cellular functions. Kandel adds that he wouldn't be surprised if this sort of prion mechanism was discovered in areas such as cancer maintenance and even organ development.


Story Source:

The above story is based on materials provided by Whitehead Institute For Biomedical Research. Note: Materials may be edited for content and length.


Cite This Page:

Whitehead Institute For Biomedical Research. "'Mad Cow' Mechanism May Be Integral To Storing Memory." ScienceDaily. ScienceDaily, 29 December 2003. <www.sciencedaily.com/releases/2003/12/031228164802.htm>.
Whitehead Institute For Biomedical Research. (2003, December 29). 'Mad Cow' Mechanism May Be Integral To Storing Memory. ScienceDaily. Retrieved September 3, 2014 from www.sciencedaily.com/releases/2003/12/031228164802.htm
Whitehead Institute For Biomedical Research. "'Mad Cow' Mechanism May Be Integral To Storing Memory." ScienceDaily. www.sciencedaily.com/releases/2003/12/031228164802.htm (accessed September 3, 2014).

Share This



More Mind & Brain News

Wednesday, September 3, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
Coffee Then Napping: The (New) Key To Alertness

Coffee Then Napping: The (New) Key To Alertness

Newsy (Aug. 30, 2014) Researchers say having a cup of coffee then taking a nap is more effective than a nap or coffee alone. Video provided by Newsy
Powered by NewsLook.com
Young Entrepreneurs Get $100,000, If They Quit School

Young Entrepreneurs Get $100,000, If They Quit School

AFP (Aug. 29, 2014) Twenty college-age students are getting 100,000 dollars from a Silicon Valley leader and a chance to live in San Francisco in order to work on the start-up project of their dreams, but they have to quit school first. Duration: 02:20 Video provided by AFP
Powered by NewsLook.com
Baby Babbling Might Lead To Faster Language Development

Baby Babbling Might Lead To Faster Language Development

Newsy (Aug. 29, 2014) A new study suggests babies develop language skills more quickly if their parents imitate the babies' sounds and expressions and talk to them often. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins