While  working on a cell cycle lecture for the Education Resources web at Promega.com, I reread some classic papers describing classic cell-cycle experiments. Two of these papers describe the experiments by Murray and Kirschner showing that cyclin B synthesis and degradation are required for cycling in Xenopus oocyte extracts. When I took my first graduate-level cell biology course in 1989, these papers had just been published. I remember the instructors of the course being particularly excited about this work. (I also remember getting the events of Xenopus oocyte activation and fertilization mixed up on one of the tests for this course and realizing it about two minutes before I had to hand in my test, but I digress.)

Looking at these papers now with the eyes of someone who has followed cell biology for more years than I care to admit, with the eyes of an educator, and with the eyes of someone who now truly “gets” that science is an iterative process, I understand the instructors’ excitement. Continue reading “Spinning Wheels Go Round and Round: Classic Experiments on the Cell Cycle”