(Relatively) Recent Lab News:
Adriana Golding defends her Ph.D. thesis. Congratulation, Adriana!
Bill is elected to the ASCB council along with Stephanie Gupton, Needhi Bhalla, and Jordan Raff
Zac Swider joins the lab as a graduate student working on cortical excitability. Welcome, Zac!
Ani Michaud joins the lab as a graduate student working on cortical excitability. Welcome, Ani!
Alison Lewis defends her Ph.D. thesis. Congratulation, Alison!
Tom Burke joins the lab as a postdoc working on cell repair. Welcome, Tom!
Nick Davenport defends his Ph.D. thesis. Congratulation, Nick!
Check out the video abstract for Brian's paper on Youtube and see if you can spot all the action in the background (http://www.youtube.com/watch?v=btCY4InNmsc)!
We were also in the ASCB Cell Dance this year; ours is the third (http://ascb.org/celldance-2014/)
(Relatively) Recent papers:
Kuan-Chung Su, George von Dassow, Mark Petronczki and Bill published a paper on cytokinetic signaling in echinoderm embryos subject to a variety of manipulations in 2014 in Molecular Biology of the Cell (http://www.molbiolcell.org/content/25/25/4049.long). It turns out that a consistent feature of cytokinesis under a variety of conditions in which spindle microtubules and/or cell shape are manipulated is a population of microtubules positioned just beneath the cortex that capture the RhoGEF, Ect2. Be sure to check out the movies of toroid cleavages!
Emily Vaughan's paper on lipid microdomains and cell repair was published in 2014 in Molecular Biology of the Cell (http://www.molbiolcell.org/cgi/pmidlookup?view=long&pmid=24790096). It turns out that several different lipids sort out into concentric rings around wounds and at least one of these lipids--diacylglycerol--is important for wound repair. When considered with the patterns displayed by the Rho GTPases, actin filaments, and myosin-2, these results indicate that a considerable amount of patterning occurs in the cortex around wounds.
Bill and George von Dassow wrote an essay on single cell pattern formation that was published in Current Opinion in Cell Biology in 2014 (http://www.sciencedirect.com/science/article/pii/S0955067413001531). The general idea is that polarization events involving the actomyosin cytoskeleton can be conceptualized as pattern formation events, analogous to those that occur during early embryogenesis.
If you are bored, you can read a "Questions and Answers" (sort of like an interview) that Bill did for Current Biology. The link is: http://www.sciencedirect.com/science/article/pii/S0960982213007768.
Brian Burkel's paper on how the wound contractile arrays close was published in 2012 in Developmental Cell (http://www.sciencedirect.com/science/article/pii/S1534580712002791). This paper is interesting because the work in it supports the surprising conclusion that contractile arrays can close without contraction as a result of a "signal treadmill". The idea is that the Rho and Cdc42 undergo spatially biased flux in the GTPase cycle to ensure forward movement of the contractile array.
Andy Clark's paper on small molecule inhibitors of cytokinesis and wound healing was published in Cytoskeleton in 2012 (http://onlinelibrary.wiley.com/doi/10.1002/cm.21085/full). This study identifies two small molecule inhibitors of both cytokinesis and single cell wound repair. The fact that these inhibitors, dubbed sphinctostatin 1 and sphinctostatin 2, inhibit both cytokinesis and single cell wound repair indicates that these processes may be more closely related than is commonly understood.
Our (Emily Vaughan and Bill Bement's) collaborative paper with Cory Simon and Leah Keshet-Edelstein (University of British Columbia) just came out in Molecular Biology of the Cell (see http://www.molbiolcell.org/content/24/3/421.long). In this paper, Cory and Leah developed a computational model to describe some of the basic features of Rho and Cdc42 activation, and the control of these GTPases by Abr, during single cell wound repair. In addition to capturing several essential features of the wound response, the model also made nonintuitive predictions about patterns of Rho and Cdc42 activity when wounds are made at varying distances from each other. Experiments in vivo confirmed these predictions as shown below: the top of the figure shows the predictions made by the model: wounds made close to each other (far left and middle) are predicted to undergo fusion of the Rho zones (green); those made a little farther apart (middle and far right) are predicted to undergo fusion of the Cdc42 zones (red). The bottom part of the figure shows that this is exactly what happens in vivo (red = active Cdc42; green = active Rho).