Navigation Links
New Way to Open Cellular Ion Channels, Implications for Drug Design

Using an enzyme found in the venom of the brown recluse spider, researchers at the University of Pennsylvania School of Medicine have discovered a new way to open// molecular pores, called ion channels, in the membrane of cells.

The research team – Zhe Lu, MD, PhD; Yajamana Ramu, PhD; and Yanping Xu, MD, PhD of the Department of Physiology at Penn – screened venoms from over 100 poisonous invertebrate species to make this discovery.

The enzyme, sphingomyelinase D (SMase D), splits a lipid called sphingomyelin that surrounds the channel embedded in the cell membrane. As a result, the channel opens to allow the passage of small ions into and out of the cell, thereby generating electrical currents.

The new study, published online earlier this month in the journal Nature, describes how SMase D opens one type of ion channel called a voltage-gated potassium channel (from brain, but experimentally expressed in the membrane of an oocyte, or egg cell) without changing the membrane voltage. The finding introduces a new paradigm for understanding the gating of ion channels and lays the conceptual groundwork for designing new drugs to control ion-channel activity in medical intervention.

Voltage-gated ion channels are embedded in the cell membranes of most types of cells. It has been known for over half a century that the channels open and close in response to changes in electric voltage across the cell membrane, hence their name. In some the cells, (commonly called “excitable”), such as nerve, muscle, heart, and hormone-secreting cells, the channels underlie electrical signaling. They selectively allow the passage of small ions such as sodium, potassium, or calcium into and out of the cell. The precisely controlled passage of ions generates the electrical currents that enable nerve impulse transmission, hormone secretion, and muscle contraction and relaxation. When there are changes to the channel, such as by mutations in a chan nel gene, disease can result. For example, mutations in some channel genes cause cardiac arrhythmias, including a form of the lethal long QT syndrome.

Voltage-gated ion channels are also present in the so-called non-excitable cells (such as immune, blood, and bone cells) whose membrane voltage stays largely constant, as opposed to the excitable cells whose membrane voltage constantly varies in a precisely controlled manner. How the activity of channels in non-excitable cells is regulated has been a long-standing biological mystery. This new finding that SMase D can open ion channels without changing membrane voltage provides a clue to the mystery.

(Source: Newswise
'"/>




Related medicine news :

1. Use of Cellular Phones associated with Increased risk of Brain Tumors
2. Researchers Discover Two Proteins Involved In Cellular Destruction Of HIV Virus
3. Unchecked Cellular Repair Pathway Causes Liver Cancer
4. Cellular System Causing Destruction Of Faulty Proteins In Cystic Fibrosis Identified
5. Gene May Regulate Cellular Aging
6. Cellular Cues Identified for Stroke Recovery
7. Cellular Pathway Yields Potential New Weapon in Vaccine Arsenal
8. Cocaines Use During Pregnancy May Cause Lasting Cellular Effects
9. Genetic Eye Disorder Can Have Other Implications
10. Implications of Statin Therapy in Bladder Cancer Patients
11. First Vaccine Designed for Africa Cleared for Testing in Humans
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:7/24/2017)... ... 2017 , ... Peruvian Ayahuasca retreat, East West Lodge, announced ... and divided between two full-time university students enrolled in U.S. or Canadian accredited ... apply for the scholarship, students are asked to submit an essay between 750 ...
(Date:7/24/2017)... ... ... The International Essential Tremor Foundation (IETF) will host a free educational forum in ... take place on Saturday, Aug. 26 at the Embassy Suites by Hilton Cleveland Rockside ... a.m. to 12 p.m., with check-in beginning at 8 a.m. The event is sponsored ...
(Date:7/24/2017)... ... , ... Every year, thousands of dedicated Higher Education and K12 professionals flock ... coupled with a dynamic theme like Camp Canvas; this year, they’ve managed to take ... , To extend their partnership with Canvas beyond the LMS integration, Modo Labs secured ...
(Date:7/24/2017)... CA (PRWEB) , ... July 24, 2017 , ... ... financial organizations, today announced it has partnered with WALLIX to expand its ... Publication 800-171 . , There are a number of ways to address the authentication ...
(Date:7/24/2017)... ... July 24, 2017 , ... The Topricin Companies, formerly Topical ... Topricin’s revolutionary, natural, after-burn skin care product, Topricin After Burn Cream. ... term skin conditions, including cancer. In the short term, overexposure to sun, ...
Breaking Medicine News(10 mins):
(Date:7/24/2017)... -- Diplomat Pharmacy, Inc. (NYSE: DPLO ) announced ... operating results on Monday, August 7, 2017 after market ... p.m. ET. Shareholders ... of the conference call by dialing 877-201-0168 or 647-788-4901 ... 15 minutes prior to the call. A live webcast ...
(Date:7/21/2017)... EDMONTON, Alberta , July 21, 2017  IBM ... of Alberta in Edmonton, Canada ... journal, Schizophrenia 1 , demonstrating that AI and ... with 74% accuracy. This retrospective analysis also showed ... in schizophrenia patients with significant correlation, based on ...
(Date:7/21/2017)... SPRING, Md. and RESEARCH TRIANGLE ... United Therapeutics Corporation (NASDAQ: UTHR ) announced ... financial results before the market opens on Thursday, July ... Therapeutics will host a teleconference on Thursday, July 27, ... accessible by dialing 1-877-351-5881, with international callers dialing 1-970-315-0533.  ...
Breaking Medicine Technology: