Course: Cell Biology: Signaling
Length: 5 weeks, 4-6 hrs/wk
Instructor: Iain Cheeseman, Frank Solomon
This is the second cell biology course in a four-part series…. these cell biology courses transition to a comprehensive discussion of biology at an experimental level. How do we know what we know about cells at a molecular level and how can we use that knowledge to design experiments to test hypotheses in cell biology?
….You will embark on a lively journey through cellular signaling mechanisms, regulation, and specific examples and learn how to apply key concepts and themes of this dynamic experimental science to understand the fundamental workings of cells.
Short version: Another great bio class from MIT.
I took the first part of this unfolding four-part series last summer, covering transport within the cell. I wish I’d thought to review it before starting this part, because, while it isn’t essential, there was enough overlap that some refreshing would have been helpful, particularly when it came to assays. But no matter, I’m probably going to take the entire sequence over when it’s complete. For that matter, I’m probably going to take the entire MIT Bio curriculum again, since I feel like I’d do a lot better, and get a lot more out of, the earlier courses now that I’m beginning to feel more familiar with cellular processes and lab techniques. Repetition truly is everything. In a normal university setting, I’d be in these classes all the time, but with moocs, they end up spread out months, years apart, so the accumulation process is slower.
Primarily the course covers various signaling pathways: G-proteins, which send second messengers out to start cascades; various pathways that use dimerization and autophosphorylation to start a signal; and a few more specific paths, like insulin, epinephrine, and RTKs, and some general cell reactions like the Unfolded Protein Response. As with all MIT bio courses, the emphasis is on experimentation, both historical and contemporary, to discover how pathways work and to confirm or discard hypotheses, rather than on memorizing individual players in each pathway. Thought questions — “how might you verify that X is necessary or sufficient?” — show up frequently, since the idea is to generate the skill of thinking as a scientist. A couple of the features introduced in Part 1 were repeated here (see that course for details): “Neat Experiments” showing how certain features were initially discovered; and Mudslips (a forum for clarifying points that seemed unclear in the lectures). The forums were active and well-covered by staff, presumably grad students.
The course is labeled as Advanced, but don’t let that intimidate you. I wouldn’t consider myself an Advanced bio student by any means, and while parts of it were difficult, it was at a good level for me. It wouldn’t be the best first bio course; if you’re not comfortable with concepts like ligands, receptors, domains, and the compartments of a cell, it might be better to pick that up first. Since there’s an emphasis on experiments, some familiarity with common procedures — blots, gels, that sort of thing — is assumed. Some review material in experimental design and processes is included, including a very helpful tutorial on Western Blot. While there’s no substitute for actual lab experience – which of course moocs can’t provide – they do a pretty good job of conveying the thought process behind various procedures.
Grading follows the usual combination of after-video questions, unit quizzes, and tests. The audit track (that is, free of charge) includes two tests, as well as after-video questions and weekly quizzes; the third test is for those on the Verified track only ($99).
Someone pointed out in the forums that it can be difficult to understand the pathways one of the professors is outlining, since his lecture style is somewhat erratic due to his enthusiasm (I suspect he’s beloved by in-person students). As compensation, online students have access to Youtube, which covers the pathways mentioned, even if not in the same terms. I found it much easier understand – and enjoy – the lectures about UPR, for instance, once I’d found a couple of Youtube videos that were more straightforward about the actual steps. By the way, this problem is not unique to this course; it comes up in most team-teaching courses, and I suspect it’s deliberate to pair instructors with different styles since some students will gravitate towards each. It’s quite possible more advanced students would prefer a more effusive style, since they’re already on board with the basics.
I’m really psyched about the next installment, coming this summer, covering the Cell Cycle. In every mitosis lecture, there are a couple of checkpoints where “the cell checks to see if everything’s ok before going on to the next step” but I’ve never seen an explanation how it knows whether everything’s ok. Now I get to find out!