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:9/22/2017)... (PRWEB) , ... September 22, 2017 , ... ... operations and financial setbacks, a senior finds a new lease on life with ... helped thousands of people resolve their problem with unsecured debt. The senior is ...
(Date:9/22/2017)... ... September 22, 2017 , ... “Cursed with ... an obligatory tithe, and the freedom experienced when breaking free from this misconception. ... author, Lysa M. Harrison. , Published by Christian Faith Publishing, Lysa M. Harrison’s ...
(Date:9/22/2017)... ... ... “Fruit of the Spirit: “Love””: a delightful adventure of two friends who play ... Spirit: “Love”” is the creation of published author, Halimah Jones, who was born and ... an avid writer, her inspiration for “Fruit of the Spirit: “Love”” blossomed from her ...
(Date:9/21/2017)... ... September 21, 2017 , ... With ProSlideshow Portrait from Pixel Film Studios ... Users can select from up to two layers of subject matter along with fully ... all within Final Cut Pro X. , With ProSlideshow Portrait each user ...
(Date:9/21/2017)... (PRWEB) , ... September 21, 2017 , ... ... **An FDAnews Management Report**, http://www.fdanews.com/products/54818-promotional-communication      , In the competitive world of ... can get while staying in compliance with FDA rules. , The FDA has ...
Breaking Medicine News(10 mins):
(Date:9/6/2017)... , Sept. 6, 2017   PDI , a leader ... will host an educational session focused on the role ... (CLABSI) prevention at the 2017 Annual Scientific Meeting of ... take place at the Phoenix ... from Sept. 16-19, will also feature PDI,s Prevantics® ...
(Date:9/5/2017)... 2017 Sapheneia and Scannerside received FDA 510(k) ... is a third-party Vendor neutral CT product that makes ... compliance with current MITA standards. ... solution is specifically designed to provide CT operators, prior ... doses over a predefined threshold. Scannerside Dose Check is ...
(Date:9/5/2017)... 5, 2017  Just 18 months after its February ... to announce the appointment of three new senior people ... Dominic Jones-Phillips and James Wright ... Tammy Wynne joins ... access writers. She has over ten years, experience in ...
Breaking Medicine Technology: