Our lab is focused on the question of how cells dynamically assemble and reorganize their actin cytoskeletons to govern cell shape, cell movement, and cell division. Every cell type has a unique architecture tailored to its physiological functions, which is defined in large part by its cytoskeleton. The cytoskeleton is a vast system of interconnected polymeric tubes and fibers that creates a dynamic scaffold used to produce polarity and compartmentalization, and to generate force. The primary aim of our research is to understand how cells bring about rapid and precise rearrangements of their actin polymer networks, transforming cell shape and function.
Actin filament networks are complex, self-assembling biological machines built from hundreds of distinct components and moving parts. We have been dissecting the inner workings of these force-producing machines, analyzing the cellular functions and biochemical mechanisms of actin regulatory proteins in order to understand how this machinery collectively orchestrates the assembly, reorganization, and disassembly of entire actin networks. Our goal is to obtain a highly mechanistic and quantitative view of these events.
We use two different in vivo systems: (a) the budding yeast S. cerevisiae, which offers advanced genetic analyses; and (b) mammalian fibroblasts and primary cardiomyocytes, which offer superior cytology and enable us to study actin regulation underlying cell motility and muscle contraction. Two fundamental questions are being addressed in the lab:
- How is the rapid assembly and disassembly of actin networks governed? To answer this question, we are studying the roles of crucial actin regulatory proteins that alter polymer dynamics, e.g. formins, Arp2/3 complex, and ADF/cofilin (figure 1). We have also identified novel binding partners of these regulators that have surprising new activities. This work includes the characterization of: (a) yeast and mammalian formins, (b) formin-binding proteins (e.g. APC, Bud6, Bud14 and Smy1), (c) WASp-Arp2/3 complex binding partners (e.g. Abp1, Syp1, coronin, and GMF), and (d) the actin disassembly and turnover machinery (e.g. Aip1, coronin, twinfilin, and Srv2/CAP).
- How is the regulation of actin dynamics coordinated with regulation of other cytoskeletal polymer systems (microtubules, septins, and intermediate filaments)? Our recent work in this area addresses functional cross-talk between the actin and microtubule cytoskeletons regulated by a triad of mammalian proteins that physically associate: (a) the tumor suppressor protein Adenomatous polyposis coli (APC), (b) the formin Dia1, and (c) the microtubule end-binding protein EB
To answer the questions above, we are taking a multidisciplinary approach combining genetics, biochemistry, structural biology, and live cell imaging. In vitro analyses include quantitative fluorescence-based kinetic assays, time lapse TIRF microscopy on individual actin filaments, single molecule analysis on actin regulatory proteins, and reconstituted actin-based bead motility assays in cell extracts and purified systems. In vivo analyses include forward and reverse genetic screens, RNAi silencing, live-cell imaging to track cytoskeletal regulatory protein dynamics and polymer dynamics, and electron microscopy (figure 2).
Recent Publications (2012-present)
Gould, C.J., M. Chesarone-Cataldo, S.L. Alioto, B. Salin, I. Sagot, and B.L. Goode. S. cerevisiae Kelch proteins and Bud14 form a stable 520 kDa formin-regulatory complex that controls actin cable assembly and cell morphogenesis. J. Biol. Chem. 2014 May 14. [Epub ahead of print].
Graziano, B.R. H.Y. Yu, S.L. Alioto, J.A. Eskin, C.A. Ydenberg, D.P. Waterman, M. Garabedian, and B.L. Goode. The F-BAR protein Hof1 tunes formin activity to sculpt actin cables during polarized growth. Mol Biol Cell. 2014 Jun 1;25(11):1730-43.
Smith B.A., J. Gelles, and B.L. Goode. Single-molecule studies of actin assembly and disassembly factors. Meth Enz. 2014; 540:95-117.
Chaudhry, F., S. Jansen, K. Little, C. Suarez, R. Boujemaa-Paterski, L. Blanchoin, and B.L. Goode. Autonomous and in trans functions for the two halves of Srv2/CAP in promoting actin turnover. Cytoskeleton. 2014 Mar 11. [Epub ahead of print].
Rosado, M. C.F. Barber, C. Berciu, S. Feldman, S.J. Birren, D. Nicastro, and B.L. Goode. Critical roles for multiple formins during cardiac myofibril development and repair. Mol Biol Cell. 2014 Mar;25(6):811-27.
Jaiswal, R., D. Breitsprecher, A. Collins, I.R. Correa, M.Q. Xu, and B.L. Goode. The formin Daam1 and fascin directly collaborate to promote filopodia formation. Curr. Biol. 2013 Jul 22; 23:1373-1379.
Ydenberg, C.A., S.B. Padrick, M.O. Sweeney, M. Gandhi, O, Sokolova, and B.L. Goode. GMF severs actin-Arp2/3 complex branch junctions by a cofilin-like mechanism. Curr Biol. 2013 Jun 17;23(12):1037-45.
Graziano, B.R., E.M. Jonasson, J.G. Pullen, C.J. Gould, and B.L. Goode (2013). Ligand-induced activation of a formin-NPF pair leads to collaborative actin nucleation. J Cell Biol. 2013 May 13;201(4):595-611.
Breitsprecher, D., and B.L. Goode. Formins at a glance. J Cell Sci. 2013 Jan 1;126:1-7.
Chaudhry, F., D. Breitsprecher, K. Little, G. Sharov, O. Sokolova, and B.L. Goode. Srv2/cyclase-associated protein forms hexameric shurikens that directly catalyze actin filament severing by cofilin. Mol Biol Cell. 2013 Jan;24:31-41.
Maiti, S., A. Michelot, C.J. Gould, L. Blanchoin, O. Sokolova, and B.L. Goode. Structure and activity of full-length formin mDia1. Cytoskeleton. 2012 Jun;69:393-4055.
Breitsprecher, D., R. Jaiswal, J. Bombardier, C.J. Gould, J. Gelles, and B.L. Goode. Rocket launcher mechanism of collaborative actin assembly defined by single-molecule imaging. Science. 2012 Jun 1;336:1164-1168.
View Complete Publication List on PubMed: Bruce Goode
Last review: June 24, 2014