Our Cell Division lesson covered how at the end of mitosis an actomyosin contractile ring assembles in location and with a timing dictated by the anaphase spindle.
Actomyosin rings also form in other contexts, such as when a pocket of cytoplasm buds off from a germline syncytium to form an oocyte.
Recently-graduated PhD student Jack Linehan from my lab (now doing a postdoc at NCSU) measured the size and speed of different actomyosin rings, and measured how the amount of ring proteins changed over time (were retained and compacted or were shed off). He then applied these measurements to a mathematical model of a ring made of contractile gel. The model could only fit the different experimental measurements if we made one of the model parameters different for the different kinds of rings.
That’s exciting because it makes a specific prediction about something that might be different across nature’s variations on the theme of actomyosin rings. We hope to make experimental measurements to test that prediction, soon.
Jack posted a preprint* about variations on the theme of contractile ring closure. Anonymous referees read our paper and submitted their opinions and recommendations to a scientist who’s an editor for Molecular Biology of the Cell. The editor said if we made the changes the referees suggested, he could probably accept it for publication. We are almost done with our revisions!
* pre-prints are manuscripts shared globally via the open repository BioRxiv. "Open" means anyone can access the contents - they don't have to pay $35 per paper they want to read, like for lots of for-profit journals; their university library doesn't have to pay hundreds or thousands of dollars for access to the repository like they have to for journals.
Pre-prints are not peer-reviewed. Peer review is the process by which 2, 3, or 4 (or sometimes more) usually-anonymous "peers" (research faculty at universities around the world) evaluate a manuscript according to the standards of a the journal where they paper is being considered, and their own experience and standards. They give a yes, no, or revisions required answer, and usually many comments ranging from typos to perceived conceptual errors to recommended extensions of the work. The journal editor summarizes all the comments and tells the authors what they need to do to get accepted and published. Sometimes they just reject the paper and the authors need to try somewhere else.
Pre-prints can receive comments and suggestions, but people don't do that very much yet. This could help prepare the manuscript for anonymous peer review.
Peer-reviewed publication is still the gold standard for showing you've advanced a field, but pre-prints allow the community to see what you've done even before that long process is complete.