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:

(Date:6/27/2016)... Viejo, California (PRWEB) , ... June 27, 2016 , ... ... are fully customizable inside of Final Cut Pro X," said Christina Austin - CEO ... another unique style. Final Cut Pro X users can now reveal the ...
(Date:6/27/2016)... Brooklyn, NY (PRWEB) , ... June 27, 2016 ... ... is using cutting edge technology to revolutionize the emergency ambulance transport experience for ... Many are aware of how Uber has disrupted the taxi industry through the ...
(Date:6/26/2016)... , ... June 26, 2016 , ... On June 10-11, ... of the 2016 Cereal Festival and World’s Longest Breakfast Table in Battle Creek, MI, ... the city’s history as home to some of the world’s leading providers of cereal ...
(Date:6/26/2016)... NC (PRWEB) , ... June 26, 2016 , ... Brent Kasmer, a legally blind and ... to be personalized through a fitness app. The fitness app plans to fix the two ... currently only offer a one size fits all type program , They don’t ...
(Date:6/25/2016)... , ... June 25, 2016 , ... Austin residents seeking ... American College of Mohs Surgery and to Dr. Russell Peckham for medical and surgical ... effective treatment for skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , June 24, 2016   Bay Area ... Network,s Dean Center for Tick Borne Illness ... and Rehabilitation, MIT Hacking Medicine, University of California, ... today announced the five finalists of Lyme ... disease.  More than 100 scientists, clinicians, researchers, entrepreneurs, ...
(Date:6/24/2016)... The Academy of Managed Care Pharmacy (AMCP) ... would allow biopharmaceutical companies to more easily share health ... and coverage decisions, a move that addresses the growing ... The recommendations address restrictions in the sharing of ... label, a prohibition that hinders decision makers from accessing ...
(Date:6/24/2016)... Research and Markets has announced the addition of ... report to their offering. ... The World Market for Companion Diagnostics covers the world market ... the report includes the following: , World ... Region (N. America, EU, ROW), 2015-2020 , World IVD ...
Breaking Medicine Technology: