University of California, Davis

• BIS 104

• BIS104 Final Exam, Form A 2 1. BiP is normally a component of the ER lumen. You add a PKKKRKV to the middle of an otherwise normal BiP. Where would you now predict the new protein to localize? A. The ER B. Secreted outside the cell C. The Golgi D. The nucleus E. The lysosome 2. You remove a KKVI sequence from the C-terminus of the KDEL receptor. Where would you now find the majority of BiP? A. Outside the cell B. The ER C. The cytoplasm D. The Golgi E. The lysosome 3. You delete the first eight AND the last four amino acids of BiP. Where would you now predict the majority of BiP to now localize? A. Outside the cell B. The ER C. The cytoplasm D. The Golgi E. The lysosome 4. You isolate a loss-of function mutation in a bacterial gene that codes for a enzyme that normally de-saturates fatty acids. What effect on the properties of the membrane would you expect such a mutation to have? A. An increase in the number of carbon double bonds and an increase in membrane fluidity. B. A decrease in the number of carbon double bonds and a decrease in membrane fluidity. C. An increase in the number of carbon double bonds and an increase in the levels of cholesterol. D. An increase in the number of carbon double bonds and a decrease in membrane fluidity. E. A decrease in the number of carbon double bonds and an increase in membrane fluidity. 5. Which statement BEST describes the role of metalloproteases in cancer progression. A. Metalloproteases degrade growth factors and therefore act a tumor suppressors. B. Metalloproteases play a role in apoptosis (programmed cell death). C. Metalloproteases induce cell growth and division and act as oncogenes. D. Metalloproteases block metastasis, and therefore act as tumor suppresors. E. Metalloproteases help recruit blood vessels to the tumor. BIS104 Final Exam, Form A 3 For questions 6-8: You clone a cDNA encoding a possible transmembrane protein. The mRNA made from the cDNA is translated in vitro in the presence of S 35 methionine and treated as indicated below before being resolved by SDS-PAGE and visualized by autoradiography. 6. Why is the protein in lane 3 smaller than the one in lane 1? A. The protein in lane 3 is cytoplasmic B. The protein in lane 3 fails to be translocated into microsomes C. The protein in lane 1 has been N-linked glycosylated D. The protein in lane 3 is missing its signal peptide and is not glycosylated E. The protein in lane 3 is unfolded + + + + + + + microsomes + + + + protease 35S meth + + + + reticulocyte lysate salt-stripped microsomes tunicamycin + + mRNA Q + + + + 100 kDa 50 kDa 25 kDa 75 kDa BIS104 Final Exam, Form A 4 7. Which of the following best describes the topology of the protein? A. It crosses the membrane five times with its C-terminus in the ER lumen. B. It crosses the membrane four times with its N-terminus in the ER lumen. C. It crosses the membrane three with its N-terminus in the cytosol. D. It crosses the membrane three with its N-terminus in the ER lumen. E. It crosses the membrane three times with its N-terminus in the cytosol 8. Why is there no protein in the last lane (lane 6)? A. Lane 6 is missing SRP receptor B. Lane 6 is missing SRP C. In lane 6, the microsomes are permeable to the protease D. Lane 6 is missing signal peptidase E. In lane 6, the translocon is always open 9. The KASH proteins UNC-83 functions to move nuclei through what mechanism? A. It recruits myosin to the surface of the nucleus to move it along actin filaments B. It recruits myosin to the surface of the nucleus to move it along intermediate filaments C. It recruits kinesin to the surface of the nucleus to move nuclei toward the minus ends of microtubules D. It recruits kinesin to the surface of the nucleus to move nuclei toward the plus ends of microtubules E. It recruits dynein to the surface of the nucleus to hold on to fluxing microtubules 10. The Starr lab added the KASH domain o