Featured Research

from universities, journals, and other organizations

Gene Called Flower Missing Link In Vesicle Uptake In Neurons

Date:
September 4, 2009
Source:
Baylor College of Medicine
Summary:
As part of synaptic transmission from one neuron to the next, bubbles containing neurotransmitters that make information exchange possible, travel to the tip of neurons, where they fuse with the cell's membrane. The extra membrane is captured in a process called endocytosis and recycled to enable the next cycle. Exocytosis must be tightly coupled with endocytosis to sustain rapid neurotransmission, researchers report.

As part of the intricate ballet of synaptic transmission from one neuron to the next, tiny vesicles – bubbles containing the chemical neurotransmitters that make information exchange possible—travel to the tip of neurons (synapses), where they fuse with the cell's membrane (a process called exocytosis). The extra membrane is then captured in a process called endocytosis and recycled to form a new vesicle to enable the next cycle of release. Most important, exocytosis must be tightly coupled with endocytosis to sustain rapid neurotransmission, said researchers from Baylor College of Medicine in a report that appears in this week's issue of the journal Cell.

Calcium influx into the synapses through tiny pores or channels in the membrane initiates the release of vesicles via exocytosis. Since neurons can fire impulses as frequently as 500 times a second, the calcium that flows into the synapses must be removed very rapidly to keep the process going.

After exocytosis, the vesicle membranes must be retrieved, and this process is also stimulated by an increase in calcium in the synapses, but the channel that mediates this influx was unknown until Dr. Hugo Bellen, a professor of molecular and human genetics at BCM, and his colleagues identified it in an elegant series of experiments. Interestingly, this channel is present in the vesicles. Hence, the vesicles carry the means to activate their own re-uptake in the form of a protein that functions as a calcium channel.

A genetic screen identified a novel gene called flower, and Chi-Kuang Yao, a postdoctoral fellow in Bellen's laboratory, mapped the gene and showed that the corresponding protein is present in the membrane of synaptic vesicles. He then showed that fruit flies lacking this gene were less able to endocytose vesicles.

Direct experiments involved purifying the Flower protein, putting it into liposomes or artificial vesicles and showing that several copies of the protein can aggregate together and form a channel in membranes. When calcium was introduced into this system, it could enter the vesicle, showing that the protein allows calcium entry.

"The vesicle carries its own channel to promote endocytosis," said Bellen. "It is a simple regulatory system. The mechanism links exocytosis and endocytosis."

Bellen is director of the BCM program in developmental biology and a Howard Hughes Medical Institute investigator.

Others who took part in this research include Yong Qi Lin, Cindy V. Ly, Tomoko Ohyama, Claire M. Haueter, Vera Y. Moiseenkova-Bell and Theodore G. Wensel, all of BCM.

Funding for this work came from the National Institute of Neurological Diseases and Stroke, the BCM Intellectual and Developmental Disabilities Research Center and the Howard Hughes Medical Institute.


Story Source:

The above story is based on materials provided by Baylor College of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. Chi-Kuang Yao, Yong Qi Lin, Cindy V. Ly, Tomoko Ohyama, Claire M. Haueter, Vera Y. Moiseenkova-Bell, Theodore G. Wensel, Hugo J. Bellen. A Synaptic Vesicle-Associated Ca2 Channel Promotes Endocytosis and Couples Exocytosis to Endocytosis. Cell, 2009; DOI: 10.1016/j.cell.2009.06.033

Cite This Page:

Baylor College of Medicine. "Gene Called Flower Missing Link In Vesicle Uptake In Neurons." ScienceDaily. ScienceDaily, 4 September 2009. <www.sciencedaily.com/releases/2009/09/090903163601.htm>.
Baylor College of Medicine. (2009, September 4). Gene Called Flower Missing Link In Vesicle Uptake In Neurons. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2009/09/090903163601.htm
Baylor College of Medicine. "Gene Called Flower Missing Link In Vesicle Uptake In Neurons." ScienceDaily. www.sciencedaily.com/releases/2009/09/090903163601.htm (accessed October 2, 2014).

Share This



More Health & Medicine News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com
Insertable Cardiac Monitor

Insertable Cardiac Monitor

Ivanhoe (Oct. 1, 2014) A heart monitor the size of a paperclip that can save your life. The “Reveal Linq” allows a doctor to monitor patients with A-Fib on a continuous basis for up to 3 years! Video provided by Ivanhoe
Powered by NewsLook.com
Attacking Superbugs

Attacking Superbugs

Ivanhoe (Oct. 1, 2014) Two weapons hospitals can use to attack superbugs. Scientists in Ireland created a new gel resistant to superbugs, and a robot that can disinfect a room in minutes. Video provided by Ivanhoe
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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