Navigation Links
Think fast! Rice undergrad unlocks nerve speed secret

In the second it takes you to read these words, tens of thousands of vesicles in your optic nerves are released in sequence, opening tiny surface pores to pass chemical signals to the next cell down the line, telling your brain what you're seeing and your eyes where to move. Thanks to two new studies ?including one spearheaded by an undergraduate biochemistry student at Rice University and published online today by Nature Structural and Molecular Biology ?scientists have defined the function of a key protein that nerve cells use to pass information quickly.

Like all cells in our bodies, nerve cells are encased in a membrane, a thin layer of fatty tissue that walls off the outside world from the cell's interior. And like other cells, nerve cells use a complex system of proteins as sensors, switches and activators to scan the outside world and decide when to open membrane doorways to take in food, expel waste and export chemical products to the rest of the body.

Many studies suggest that a group of proteins called SNAREs act like the cell's loading dock managers, deciding when to open the door to release shipments of chemical freight. SNAREs form a docking bay for cartons of chemicals encased in their own fatty membranes.

"Nerve cells are one of the few cells in our bodies in which vesicles are prepositioned at the cell membrane, because they have to be ready to release neurotransmitter to the next nerve cell at a moment's notice," said principal researcher James McNew, assistant professor of biochemistry and cell biology.

SNAREs are a key player in membrane fusion. They oversee the merger of the cell's outer membrane with the membrane encasing the chemical freight, and they do it in such a way that the freight can be exported, but no outside cargo can enter.

"With nerve cells, we've known that SNAREs provide the mechanical energy for membrane fusion, and another protein called synaptotagmin is the actuator," McNew said. "We also knew there was a chemical brake in the system, something that held the pre-positioned vesicle in check, but poised for release. These new studies clearly show that the brake is a protein called complexin."

Rice's study, which was conducted in McNew's lab, largely by undergraduate Johanna Schaub, involved in vitro experiments on a synthetic and highly controlled complex of membranes and proteins. Via these experiments, Schaub was able to show that SNARE-driven membrane fusion ?the act that opens the door for neurotransmitter to leave the neuronal cell ?was inhibited by complexin.

"By halting fusion partway, complexin essentially shortens the response time for signal transmission," said Schaub, who will begin graduate school at Stanford University in the fall. "The nerve cell can almost instantaneously pass on its information."

McNew said the finding is independently confirmed by work published online June 22 by Science magazine. In that study, Columbia University's James Rothman and colleagues created mutant cells with SNAREs on the outside rather than the inside, and they used the cells to show that complexin could inhibit fusion that would otherwise be expected to proceed.

"Complexin is the brake," McNew said. "It says, 'Stop. Don't go any further until you get the signal from synaptotagmin.'"


'"/>

Source:Rice University


Related biology news :

1. Thinking the pain away? Study shows the brains painkillers may cause placebo effect
2. Thinking with the spinal cord?
3. Wisconsin scientists grow critical nerve cells
4. Clam embryo study shows pollutant mixture adversely affects nerve cell development
5. Zebrafish may hold key to understanding human nerve cell development
6. New component of the brakes on nerve regeneration found
7. Cerebral navigation: How do nerve fibers know what direction to grow in?
8. Molecular messengers perform a crucial role in the ability of injured nerve cells to heal themselves
9. Diabetic nerve therapy shows striking results
10. Malfunctioning bone marrow cells sabotage nerve cells in diabetes
11. UIC researchers show protein routes messages in nerve cells
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:11/29/2016)... 2016   Neurotechnology , a provider ... technologies, today released FingerCell 3.0, a software ... that run on low-power, low-memory microcontrollers. FingerCell ... than 128KB of memory, enabling it to ... limited on-board resources, such as: mobile phones, ...
(Date:11/22/2016)... 2016 According to the new market research report ... Vein, Signature, Voice), Multi-Factor), Component (Hardware and Software), Function (Contact and Non-contact), ... market is expected to grow from USD 10.74 Billion in 2015 to ... 2016 and 2022. Continue Reading ... ...
(Date:11/17/2016)... , Nov. 17, 2016 Global Market Watch: ... Biobanks (Disease-Based Banks, Population-Based Banks and Academics) market is to ... for Private Biobanks shows the highest Compounded Annual Growth Rate ... region during the analysis period 2014-2020. North ... of 9.95% followed by Europe at ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... OXFORD, England , December 8, 2016 /PRNewswire/ ... (OGT), das Unternehmen für Molekulargenetik, erweitert seine Palette ... SureSeq myPanel™ NGS Custom FH Panels, das ein ... Hypercholesterinämie (FH) ermöglicht. Das Panel bietet eine Erkennung ... Number Variations (CNV) mit einem einzigen kleinen Panel ...
(Date:12/8/2016)... ... December 08, 2016 , ... KBioBox ... response to client demand KbioBox developed a sophisticated “3 click” gene dditing off ... accessible from KBioBox’s new website, https://www.kbiobox.com/ and powered by the ...
(Date:12/8/2016)... ... ... This CAST literature review and report looks at problems caused by the current ... in countries that are major global commodity exporters and importers, which show that asynchrony ... level presence (LLP) puts large volumes of trade worth billions of dollars at risk. ...
(Date:12/8/2016)... TAMPA, Fla. , Dec. 8, 2016 /PRNewswire/ ... biopharmaceutical company that discovers, develops and plans to ... today that its shares of common stock were approved ... stock will begin trading on the OTCQX, effective ... To qualify for the OTCQX market, companies must ...
Breaking Biology Technology: