1. Subcellular Self-Assembly Spontaneous Building of Complex Structures

2. Mitosis in sand dollar blastula

4. What was involved in the self- assembly of the microtubule? GTP Tube formation Tubulin Growing and shrinking Peeling and curving Change in shape

5. Brainstorm! There exists a plethora of self- assembly examples in biology

6. 100 nm Self-assembly is critical at the nano-scale

7. Modeling self-assembly Arrange the marbles. Agitate gently. Observe the pattern.

8. What structure formed for you? Why did the marbles stick together? How did they “know” how to stick together to form a circle?

9. Why did the marbles stick together? Self-assembly requires a template.

10. Was the attraction strong or weak? The bonds holding the structure together must be fairly weak.

11. What drove the marbles together? Self-assembly must have an energy source.

12. Requires a template. Must have an energy source. The bonds holding the structure together must be fairly weak. Self-assembly has rules

13. Make your own template Generate this structure Use magnets Design before you build. Shake the pieces to assemble the structure.

14. What rules of self-assembly were incorporated into your model? Was there a template? Were the bonds fairly weak? Was there an energy source?

15. Viruses demonstrate self-assembly

16. You may be familiar with the bacteriophage

17. Viruses differ from bacteriophages.

21. Let’s look at some of the parts of self-assembly Station A –Shake the capsomers to completely assemble the capsid. –Disassemble the capsid with a quick shake of the jar. Station B –View a drop of India ink under low power. –Observe under high power. –Move low power back into place.

22. What’s the connection between what you observed at the two stations? Brownian MotionShaking

23. What was the template for the capsid? Design a template for assembly of a viral capsid. Assemble the capsid. Remember, only sides with opposite charges can be connected. + -

24. How did you do? - - - - - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - - - - -

25. Virus capsids are based upon simple geometric designs Where is the template stored? Each kind of capsid part needs its own gene. Fewer different kinds of parts = less DNA needed!

26. Virus capsid assembly

27. These models were based on corannulene components

28. ---C - N H ---C - O O = C ---- H H -- ++ ++ ++ Hydrogen bonds hold them together.

29. Can you figure out how to put them together?

34. Viruses are subcellular structures that self-assemble Brownian motion provides the energy. Hydrogen bonds are easy to make and easy to break. DNA provides the template for the proteins capsomers.