Aquaporins: Investigating the Structure and Function Cell Membrane Water Channels

Interdisciplinary Investigations (IDI) Chemistry 161 Chemistry 162 Chemistry 163 Epigenetics Aquaporins Day 1 Pre-Lab Discussion Part 1: Aquaporins Part 2: IDI Challenge 1 Day 2 Part 3: Seminar Part 4: IDI Challenge 2 Part 5: Post-lab Assignment

What did you find most interesting about each video? Pre-Lab Discussion What did you find most interesting about each video?

The Fluid Mosaic Model of the Cell Membrane

Key Structural Component: The Phospholipid Think/ Pair/ Share: What do you notice about the structure of this molecule? Think/ Pair/ Share: What does this mean for the intermolecular forces between these molecules?

Key Structural Component: The Phospholipid

Key Structural Component: A Mosaic of Proteins

A Quick Look at Protein Structure

A Quick Look at Protein Structure

Key Features of Membrane Proteins Think/ Pair/ Share: What must be true about the structure of proteins that span the cell membrane?

Visualizing the Cell Membrane: https://www.youtube.com/watch?v=LKN5sq5dtW4&list=PL13jH2BYL65_q5j1vBga32xNiYT57P5KC

Crossing the Cell Membrane What types of things does a cell need to get across its membrane? Of those things, which can cross freely?? Why?? What about everything else??

X Cell membranes are SELECTIVELY PERMEABLE O2, CO2, and other small, nonpolar molecules; and H2O large, polar molecules; ions such as H+, Na+, CI-, Ca++; X

Part 1 B: Intermolecular Forces & Cell Membranes

Part 1 B: Intermolecular Forces & Cell Membranes

C. Hydrogen Bonding

D. Amino Acid ~ Arginine

Part 2: IDI Challenge On your white board, make a group drawing that represents your understanding of protein structure and intermolecular forces to construct a model (drawing) of what a water channel in a cell membrane would look like, and how it would orient itself in a plasma membrane. Would such a channel need to be specific for water? If so, how could it accomplish this specificity? Be sure to capture your drawing as a photograph for your post-lab report!

Part 3: Seminar Assignment For Next Week: Read these two articles: “Precious Bodily Fluids”, Pittsburgh Supercomputing Center, 2002 Another article about water channels?? 2. Write a summary of the articles. 3. Write three questions 4. Bring the summary and questions with you to class and be prepared to participate in an in-class seminar

Day 2 Agenda Your Drawings… Hydrogen Bonds! Seminar Challenge #2

Group 1

Group 2

Group 3

Group 4

Group 5

Hydrogen Bonding Can you recognize them now? Draw an H-bond between two molecules of the following if possible: a. CH3NH2 b. CH3N(CH3)2

Part 3: Seminar Find your team! Introductions and Roles. Discuss the papers, using your questions as a guide. Report out!

Aquaporin

Amino Acid ~ Arginine

Amino Acid: Asparagine

Day 2: IDI Challenge What does the aquaporin channel look like on the atomic level? Why does water get through and other things do not? Use information from seminar and your white boards to draw a second detailed picture of the water channel. Be sure to capture your drawing as a photograph for your post-lab report!

Comparing your Models https://www.youtube.com/watch?v=GSi5-y6NHjY