lecture07,08 init

2016-10-03-lecture05.md

@@ -416,23 +416,6 @@ from wikipedia:
 
 ## Structure of the bacterial K⁺ channel
 
-<figure><figcaption class="big">Each subunit has 2 transmembrane domains, 4 subunits make a channel</figcaption><img src="figs/Neuroscience5e-Fig-04.07-2R_5838376.jpg" height="400px"><figcaption>Neuroscience 5e Fig. 4.7</figcaption></figure>
-
-Note:
-
-(Doyle et al, Science 280:69, 1998)
-
-
-<!-- ## Structure of the bacterial K⁺ channel
-
-3D structure of bacterial K channel. Yellow is the K channel, white are phospholipids, purple Na, green K.
-
-<figure><img src="figs/image4_b687955.png" height="300px"><figcaption></figcaption></figure> -->
-
----
-
-## Structure of the bacterial K⁺ channel
-
 * Bacteria have K⁺ channels that are very similar in structure to mammalian K⁺ channels. Main difference is that they are not gated by voltage 
 * Could be crystallized in the bacterial membrane
 * 3D structure tells us a lot about function
@@ -459,6 +442,24 @@ Note:
 
 (Doyle et al, Science 280:69, 1998)
 
+---
+
+## Structure of the bacterial K⁺ channel
+
+<figure><figcaption class="big">Each subunit has 2 transmembrane domains, 4 subunits make a channel</figcaption><img src="figs/Neuroscience5e-Fig-04.07-2R_5838376.jpg" height="400px"><figcaption>Neuroscience 5e Fig. 4.7</figcaption></figure>
+
+Note:
+
+(Doyle et al, Science 280:69, 1998)
+
+
+<!-- ## Structure of the bacterial K⁺ channel
+
+3D structure of bacterial K channel. Yellow is the K channel, white are phospholipids, purple Na, green K.
+
+<figure><img src="figs/image4_b687955.png" height="300px"><figcaption></figcaption></figure> -->
+
+
 ---
 
 ## Structure of a bacterial K⁺ channel determined by crystallography
@@ -598,6 +599,8 @@ Note:
 
 Yellow are voltage sensing tm domains
 
+4–8 positively-charged amino acids in the S4 domain. Experiences force in a transmembrane electric field. Is the electric-field sensor for voltage-dependent gating.
+
 K channels are more diverse
 
 - Kv2.1 show little inactivation and are closely related to the delayed rectifier K channels involved in AP repolarization
@@ -722,10 +725,15 @@ charybdotoxin from scorpions K channels
 
 ## Diseases caused by altered ion channels
 
+<div style="font-size:0.7em;">
+<div></div>
+
 EA1: episodic ataxia type 1 (abnormal limb movements and severe ataxia)  
 
 BFNC: benign familial neonatal convulsion. Frequent brief seizures starting in first postnatal week then disappearing in a few months. Mutation mapped to two K⁺ channel genes  
 
+</div>
+
 <figure><img src="figs/Neuroscience5e-Box-04D-3R_2e54724.jpg" height="300px"><figcaption>Neuroscience 5e Box 4D</figcaption></figure>