Biological complexity: ion channels (Introduction)

by David Turell , Monday, January 18, 2016, 22:07 (3011 days ago) @ David Turell
edited by David Turell, Monday, January 18, 2016, 22:13

The very complex structure is now shown:-http://www.sciencedaily.com/releases/2016/01/160118134434.htm--"Many cells have microscopic gates, called ion channels, which open to allow the flow of ions across the cell membrane. Thanks to these gates, cells can detect stimuli such as heat, pain, pressure and even spicy food.-***-"Lander and his colleagues focused on an ion channel called the transient receptor potential vanilloid-2 (TRPV2), which resides within the membranes of cells throughout the body. Previous research had suggested TRPV2 was involved in sensing physical stresses, such as changes in pressure and temperature, as well as in detecting immune challenges and activating the immune system's T cells.-"In the new study, the researchers used an imaging technique called cryo-electron microscopy, in which a sample is pelted with high-energy electrons. Through the use of new sample preparation techniques, computer programs and a new generation of cameras, researchers at TSRI have improved the potential resolution of cryo-electron microscopy images to the point that TRPV2 could be imaged with near-atomic precision.-***-"When the researchers compared the structure of TRPV2 with TRPV1, a genetically similar ion channel found only in the nervous system, they noticed some significant differences. TRPV2's architectural components near the central gate and the peripheral domains were in a previously unobserved configuration. Together, this led the authors to propose that this configuration represents a 'desensitized' state, providing a new molecular snapshot of these ion channels at work.-"'The TRVP2 ion channel is likely a global internal sensor--playing an important role in our immune response," said Lander."-Second source: http://phys.org/news/2016-01-scientists-blueprint-body-sensor.html-
&a... a hot stove, and your fingers will recoil in pain because your skin carries tiny temperature sensors that detect heat and send a message to your brain saying, "Ouch! That's hot! Let go!"
 
"The pain is real and it serves a purpose, otherwise we'd suffer greater injury. But for many people with chronic pain, that signal keeps getting sent for months or years, even when there is no clear cause.-"Now, researchers have discovered the structure of a protein linked to pain and heat perception. It is an ion channel in the cell surface membrane called TRPV2. This port-like structure plays a role in a number of disparate biological processes, such as maintaining a healthy heart, helping dispose of pathogens and inducing cell death in certain cancers."-Comment: Look at the model. How does chance evolution create this stuff?