MIT Biology Department 7.012: Introductory Biology -Fall 2004 Instructors: Professor Eric Lander, Professor Robert A. Weinberg, Dr. Claudette Gardel Name Section: 7.012 Problem set 8 Please print out this problem set and record your answers on the printed copy. answers to this problem set are to be turned in at the box outside by 4: 10 Wednesday, November 26. Problem sets will not be accepted late Solutions will be posted on the web November 27, 2003 "PLEASE NOTE Questions 1-3 cover material from lectures 23-25 and thus would be good practice for Quiz Il Question 1 You have isolated cells from an alien organism called Sacul Sinned. You want to know if these cells contain proteins that are similar to the cyclins found in eukaryotic cells. To this end, you radioactively label all the proteins in the cell to allow for visualization on a gel. You then synchronize the cells by placing them in low serum for 1 day. Finally, you stimulate the cells with PDgF and isolate protein from the cells at different time points. The proteins are then run out on a gel similar to a dna gel, such that the proteins are separated by size and you can visualize them through their radioactivit 5678 a)Circle the protein bands on the gel that would be good candidates for cyclin proteins? Explain your choices b)How many cell cycles did your time points cover if each of the protein bands you selected above are actually cyclin proteins? Explain you answer 7012fall2003Name:___________________________________ Section:_____ 7.012 fall 2003 1 7.012 Problem Set 8 *PLEASE NOTE,: Questions 1 - 3 cover material from lectures 23-25 and thus would be good practice for Quiz III. Question 1 You have isolated cells from an alien organism called Sacul Sinned. You want to know if these cells contain proteins that are similar to the cyclins found in eukaryotic cells. To this end, you radioactively label all the proteins in the cell to allow for visualization on a gel. You then synchronize the cells by placing them in low serum for 1 day. Finally, you stimulate the cells with PDGF and isolate protein from the cells at different time points. The proteins are then run out on a gel similar to a DNA gel, such that the proteins are separated by size and you can visualize them through their radioactivity. a) Circle the protein bands on the gel that would be good candidates for cyclin proteins? Explain your choices. b) How many cell cycles did your time points cover if each of the protein bands you selected above are actually cyclin proteins? Explain you answer. 1 2 3 4 5 6 7 8 Please print out this problem set and record your answers on the printed copy. Answers to this problem set are to be turned in at the box outside by 4:10 Wednesday, November 26. Problem sets will not be accepted late. Solutions will be posted on the web November 27, 2003. MIT Biology Department 7.012: Introductory Biology - Fall 2004 Instructors: Professor Eric Lander, Professor Robert A. Weinberg, Dr. Claudette Gardel