Study Questions

10-29-01 – 12-3-01

• Cite two similarities and two differences of actin/actin filaments and tubulin/microtubules.
• What is the function and general structure of myosin II?
• How does calcium control muscle contraction?
• What are the three features of myosin II and how does each relate to myosin’s function?
• You have purified protein that you suspect to be a member of the myosin family. What two methods can you use to assay this experimentally?
• What is the function and location of the troponin/tropomysoin complex?
• What two proteins serve to control calcium levels in the sarcoplasmic reticulum?
• Describe the two conclusions from the work of Pollard and Mooseker.
• How was it shown that myosin II was not required for amoeboid motility?
• What was the primary conclusion from Theriot and Mitchison’s work with keratocytes and Listeria?
• You are examining a protein that you believe is involved in capping the plus ends of actin filaments. What are two ways that you could examine this experimentally?
• What is the function and cellular location of the Arp 2/3 complex?
• List three experiments that made Listeria a useful system for understanding the workings of the actin cytoskeleton.
• What was the contribution of Svitkina and Borisy?
• How can you differentiate the plus and minus ends of actin filaments? MTs?
• What is the cause of the lag phase of actin assembly and how is this avoided in the cell?
• Compare and contrast kinesin and myosin.
• What is the function of the GTP cap?
• What controls the rate of actin filament assembly? The rate of MT assembly?
• What is the function and location of nexin?
• You have discovered a new MT motor protein. How can you assay its directionality?
• How did Vale, Reese, and Sheetz discover kinesin? How did they purify it?
• What is the function and location of CENP-E?
• What is the function and location of the kinetochore?
• What three experimental systems have been important in the study of MTs?
• How did Ian Gibbons discover axonemal dynein?
• What was the conclusion from Borisy’s experiment with the mitotic spindle?
• You believe you have found a new motor protein for mitosis. Remembering the various experiments that we have covered in class, what are two ways to study its function by inhibition?
• What was the primary conclusion of McIntosh?
• Explain the two conclusions of the myosin II knockouts.