Regulation of Actin Assembly Dynamics

GUILLAUME ROMET-LEMONNE & ANTOINE JEGOU

In cells, the assembly of actin filaments is highly regulated to give rise to different actin networks with well-controlled architectures (cortex, lamellipodia, filopodia, …). These networks allow specific cell deformations and movements, required for many processes (motility, division, endocytosis, …).

A large number of proteins interact with actin to control how, where and when actin monomers assemble into filaments. Understanding their biochemical activities can be very difficult to decipher, especially when these activities depend on the local cellular context and the mechanical constraints that apply to each filament forming these networks. Our goal is to understand the elementary processes of actin mechanosensitivity affecting actin dynamics and the action of regulatory proteins. To this end, our team is developing experimental approaches combining microfluidics, micropatterning, and optical tweezers to conduct in vitro experiments that are essential to decipher the individual molecular reactions that regulate the emergence of actin networks.

Keywords: cytoskeleton, actin, biochemistry, biophysics, mechanosensitivity, networks, mechanics

+33 (0)157278013     romet (at) ijm.fr / antoine.jegou (at) ijm.fr     @Romet_Jegou_lab    www.actindynamics.net

The assembly of ATP-actin monomers into filaments is the basis for the formation of the actin cytoskeleton in cells. The hydrolysis of ATP that occurs during this process is accompanied by a major change in the conformation of the actin subunits, and thus of the filament itself. These changes have profound consequences on the regulation of filament assembly kinetics.

In cells, actin assembly is regulated by hundreds of actin binding proteins (ABPs), which can act together, in synergy, or in competition. These ABPs can bind to the sides, ends of filaments and/or monomers and have various effects. They are generally distinguished according to their main functions: nucleators, elongators, proteins that promote filament disassembly, stabilize filaments, or proteins that link filaments to each other or to other organelles.

 

If ABPs can modify the mechanical state of actin filaments, external mechanical factors can in turn affect the activity of ABPs. We believe that this mechanochemical interaction plays a crucial role in the assembly of the actin network in cells.

To understand how ABPs and the mechanical context generate networks of various geometries, dynamics and lifetimes, our team focuses its efforts on the observation and in vitro manipulations of single actin filaments or small reconstituted networks under well-controlled conditions. Microfluidics is a very powerful tool to expose filaments to different protein solutions in a sequential manner and to expose filaments to various mechanical stresses, thus opening new avenues to decipher the dynamics of actin network assembly.

 

On the right, a sketch represents a standard microfluidic chamber with 3 inlets positioned above a microscope objective. In this chamber, actin filaments are grown from primers anchored to the surface of the experimental chamber and aligned with the flow. Dozens of fluorescently labeled actin filaments can be followed in parallel while being exposed to various biochemical conditions affecting their dynamics.

Group Leaders:

Guillaume ROMET-LEMONNE
Téléphone : +33 (0)157278013
Email : romet (at) ijm.fr

 

Antoine JEGOU
Téléphone : +33 (0)157278013
Email : antoine.jegou (at) ijm.fr

 

Members:

Foad GHASEMI Doctorant
Berengere GUICHARD Ingénieure en biologie
Camille BAGES Ingénieure en biologie
Cécile LEDUC Chercheur
Dina AL ABYAD Postdoctorant
Inaara KASSAMALY Doctorant
Ingrid BILLAULT-CHAUMARTIN Postdoctorant
Jiu XIAO Doctorant
Lilian PATY Master 2
Omar EL HAMOUI Postdoctorant
Pierre BONNESOEUR Ingénieur en biologie
Rebecca PAGES Assistante ingénieur
Wouter KOOLS Doctorant
Hugo WIOLAND Chercheur

Wioland, H., Jégou, A., and Romet-Lemonne, G. (2022). Celebrating 20 years of live single-actin-filament studies with five golden rules. Proc. Natl. Acad. Sci. U. S. A. 119, e2109506119.

Wioland, H., Frémont, S., Guichard, B., Echard, A., Jégou, A., and Romet-Lemonne, G. (2021). Actin filament oxidation by MICAL1 suppresses protections from cofilin-induced disassembly. EMBO Rep. 22, e50965.

Cao, L., Yonis, A., Vaghela, M., Barriga, E.H., Chugh, P., Smith, M.B., Maufront, J., Lavoie, G., Méant, A., Ferber, E., et al. (2020). SPIN90 associates with mDia1 and the Arp2/3 complex to regulate cortical actin organization. Nat. Cell Biol. 1–12.

Hakala, M., Wioland, H., Tolonen, M., Kotila, T., Jegou, A., Romet-Lemonne, G., and Lappalainen, P. (2021). Twinfilin uncaps filament barbed ends to promote turnover of lamellipodial actin networks. Nat. Cell Biol. 23, 147–159.

Jégou, A., and Romet-Lemonne, G. (2020). Mechanically tuning actin filaments to modulate the action of actin-binding proteins. Curr. Opin. Cell Biol. 68, 72–80.

Suzuki, E.L., Chikireddy, J., Dmitrieff, S., Guichard, B., Romet-Lemonne, G., and Jégou, A. (2020). Geometrical Constraints Greatly Hinder Formin mDia1 Activity. Nano Lett. 20, 22–32.

Wioland, H., Jegou, A., and Romet-Lemonne, G. (2019). Torsional stress generated by ADF/cofilin on cross-linked actin filaments boosts their severing. Proc. Natl. Acad. Sci. U. S. A. 116, 2595–2602.

Cao, L., Kerleau, M., Suzuki, E.L., Wioland, H., Jouet, S., Guichard, B., Lenz, M., Romet-Lemonne, G., and Jegou, A. (2018). Modulation of formin processivity by profilin and mechanical tension. Elife 7, e34176.

Wioland, H., Guichard, B., Senju, Y., Myram, S., Lappalainen, P., Jégou, A., and Romet-Lemonne, G. (2017). ADF/Cofilin Accelerates Actin Dynamics by Severing Filaments and Promoting Their Depolymerization at Both Ends. Curr. Biol. 27, 1956–1967.e7.

Shekhar, S., Kerleau, M., Kühn, S., Pernier, J., Romet-Lemonne, G., Jégou, A., and Carlier, M.-F. (2015). Formin and capping protein together embrace the actin filament in a ménage à trois. Nat. Commun. 6, 8730.

Jégou, A., Carlier, M.-F., and Romet-Lemonne, G. (2013). Formin mDia1 senses and generates mechanical forces on actin filaments. Nat. Commun. 4, 1883.

Publications

CelebicDunja, PolatIrem, LegrosVéronique, ChevreuxGuillaume, WassmannKatja, & A, T. (2024). Qualitative rather than quantitative phosphoregulation shapes the end of meiosis I in budding yeast. The EMBO Journal. https://doi.org/10.1038/s44318-024-00032-5
Ghasemi, F., Cao, L., Mladenov, M., Guichard, B., Way, M., Jégou, A., & Romet-Lemonne, G. (2024). Regeneration of actin filament branches from the same Arp2/3 complex. Science Advances, 10(4), eadj7681. https://doi.org/10.1126/sciadv.adj7681
Liu, T., Cao, L., Mladenov, M., Jegou, A., Way, M., & Moores, C. A. (2024). Cortactin stabilizes actin branches by bridging activated Arp2/3 to its nucleated actin filament. Nature Structural & Molecular Biology, 1–9. https://doi.org/10.1038/s41594-023-01205-2
Park, Y., Leduc, C., Etienne-Manneville, S., & Portet, S. (2023). Models of vimentin organization under actin-driven transport. Physical Review E, 107(5), 054408. https://doi.org/10.1103/PhysRevE.107.054408
Cao, L., Ghasemi, F., Way, M., Jégou, A., & Romet-Lemonne, G. (2023). Regulation of branched versus linear Arp2/3-generated actin filaments. The EMBO Journal, 42(9), e113008. https://doi.org/10.15252/embj.2022113008
Tran, Q. D., Sorichetti, V., Pehau-Arnaudet, G., Lenz, M., & Leduc, C. (2023). Fragmentation and Entanglement Limit Vimentin Intermediate Filament Assembly. Physical Review X, 13(1), 011014. https://doi.org/10.1103/PhysRevX.13.011014
Maufront, J., Guichard, B., Cao, L.-Y., Cicco, A. D., Jégou, A., Romet-Lemonne, G., & Bertin, A. (2023). Direct observation of the conformational states of formin mDia1 at actin filament barbed ends and along the filament. Molecular Biology of the Cell, 34(1), ar2. https://doi.org/10.1091/mbc.E22-10-0472
Dallon, J. C., Leduc, C., Grant, C. P., Evans, E. J., Etienne-Manneville, S., & Portet, S. (2022). Using Fluorescence Recovery After Photobleaching data to uncover filament dynamics. PLoS Computational Biology, 18(9), e1010573. https://doi.org/10.1371/journal.pcbi.1010573
Portet, S., Etienne-Manneville, S., Leduc, C., & Dallon, J. C. (2022). Impact of noise on the regulation of intracellular transport of intermediate filaments. Journal of Theoretical Biology, 547, 111183. https://doi.org/10.1016/j.jtbi.2022.111183
Lappalainen, P., Kotila, T., Jégou, A., & Romet-Lemonne, G. (2022). Biochemical and mechanical regulation of actin dynamics. Nature Reviews. Molecular Cell Biology. https://doi.org/10.1038/s41580-022-00508-4
Romet-Lemonne, G. (2022). Under the hood of a moving cell. ELife, 11, e81108. https://doi.org/10.7554/eLife.81108
Kotila, T., Wioland, H., Selvaraj, M., Kogan, K., Antenucci, L., Jégou, A., Huiskonen, J. T., Romet-Lemonne, G., & Lappalainen, P. (2022). Structural basis of rapid actin dynamics in the evolutionarily divergent Leishmania parasite. Nature Communications, 13(1), 3442. https://doi.org/10.1038/s41467-022-31068-y
Nunes Vicente, F., Lelek, M., Tinevez, J.-Y., Tran, Q. D., Pehau-Arnaudet, G., Zimmer, C., Etienne-Manneville, S., Giannone, G., & Leduc, C. (2022). Molecular organization and mechanics of single vimentin filaments revealed by super-resolution imaging. Science Advances, 8(8), eabm2696. https://doi.org/10.1126/sciadv.abm2696
Sonam, S., Vigouroux, C., Jégou, A., Romet-Lemonne, G., Le Clainche, C., Ladoux, B., & Mège, R. M. (2021). Direct measurement of near-nano-Newton forces developed by self-organizing actomyosin fibers bound α-catenin. Biology of the Cell, 113(11), 441–449. https://doi.org/10.1111/boc.202100014
Vignier, N., Chatzifrangkeskou, M., Pinton, L., Wioland, H., Marais, T., Lemaitre, M., Le Dour, C., Peccate, C., Cardoso, D., Schmitt, A., Wu, W., Biferi, M.-G., Naouar, N., Macquart, C., Beuvin, M., Decostre, V., Bonne, G., Romet-Lemonne, G., Worman, H. J., … Muchir, A. (2021). The non-muscle ADF/cofilin-1 controls sarcomeric actin filament integrity and force production in striated muscle laminopathies. Cell Reports, 36(8), 109601. https://doi.org/10.1016/j.celrep.2021.109601
Schmidt, E. J., Funes, S., McKeon, J. E., Morgan, B. R., Boopathy, S., O’Connor, L. C., Bilsel, O., Massi, F., Jégou, A., & Bosco, D. A. (2021). ALS-linked PFN1 variants exhibit loss and gain of functions in the context of formin-induced actin polymerization. Proceedings of the National Academy of Sciences of the United States of America, 118(23), e2024605118. https://doi.org/10.1073/pnas.2024605118
Hakala, M., Wioland, H., Tolonen, M., Kotila, T., Jegou, A., Romet-Lemonne, G., & Lappalainen, P. (2021). Publisher Correction: Twinfilin uncaps filament barbed ends to promote turnover of lamellipodial actin networks. Nature Cell Biology, 23(4), 437–438. https://doi.org/10.1038/s41556-021-00651-8
Wioland, H., Frémont, S., Guichard, B., Echard, A., Jégou, A., & Romet-Lemonne, G. (2021). Actin filament oxidation by MICAL1 suppresses protections from cofilin-induced disassembly. EMBO Reports, 22(2), e50965. https://doi.org/10.15252/embr.202050965
Hakala, M., Wioland, H., Tolonen, M., Kotila, T., Jegou, A., Romet-Lemonne, G., & Lappalainen, P. (2021). Twinfilin uncaps filament barbed ends to promote turnover of lamellipodial actin networks. Nature Cell Biology, 23(2), 147–159. https://doi.org/10.1038/s41556-020-00629-y
Fokin, A. I., David, V., Oguievetskaia, K., Derivery, E., Stone, C. E., Cao, L., Rocques, N., Molinie, N., Henriot, V., Aumont-Nicaise, M., Hinckelmann, M.-V., Saudou, F., Le Clainche, C., Carter, A. P., Romet-Lemonne, G., & Gautreau, A. M. (2021). The Arp1/11 minifilament of dynactin primes the endosomal Arp2/3 complex. Science Advances, 7(3), eabd5956. https://doi.org/10.1126/sciadv.abd5956
Palenzuela, H., Lacroix, B., Sallé, J., Minami, K., Shima, T., Jegou, A., Romet-Lemonne, G., & Minc, N. (2020). In Vitro Reconstitution of Dynein Force Exertion in a Bulk Viscous Medium. Current Biology: CB, 30(22), 4534-4540.e7. https://doi.org/10.1016/j.cub.2020.08.078
Bareja, I., Wioland, H., Janco, M., Nicovich, P. R., Jégou, A., Romet-Lemonne, G., Walsh, J., & Böcking, T. (2020). Dynamics of Tpm1.8 domains on actin filaments with single-molecule resolution. Molecular Biology of the Cell, 31(22), 2452–2462. https://doi.org/10.1091/mbc.E19-10-0586
von Loeffelholz, O., Purkiss, A., Cao, L., Kjaer, S., Kogata, N., Romet-Lemonne, G., Way, M., & Moores, C. A. (2020). Cryo-EM of human Arp2/3 complexes provides structural insights into actin nucleation modulation by ARPC5 isoforms. Biology Open, 9(7), bio054304. https://doi.org/10.1242/bio.054304
Cao, L., Yonis, A., Vaghela, M., Barriga, E. H., Chugh, P., Smith, M. B., Maufront, J., Lavoie, G., Méant, A., Ferber, E., Bovellan, M., Alberts, A., Bertin, A., Mayor, R., Paluch, E. K., Roux, P. P., Jégou, A., Romet-Lemonne, G., & Charras, G. (2020). SPIN90 associates with mDia1 and the Arp2/3 complex to regulate cortical actin organization. Nature Cell Biology, 22(7), 803–814. https://doi.org/10.1038/s41556-020-0531-y
Hugo Wioland, Suzuki, E., Cao, L., Romet-Lemonne, G., & Jegou, A. (2020). The advantages of microfluidics to study actin biochemistry and biomechanics. Journal of Muscle Research and Cell Motility, 41(1), 175–188. https://doi.org/10.1007/s10974-019-09564-4
Bai, J., Wioland, H., Advedissian, T., Cuvelier, F., Romet-Lemonne, G., & Echard, A. (2020). Actin reduction by MsrB2 is a key component of the cytokinetic abscission checkpoint and prevents tetraploidy. Proceedings of the National Academy of Sciences of the United States of America, 117(8), 4169–4179. https://doi.org/10.1073/pnas.1911629117
Suzuki, E. L., Chikireddy, J., Dmitrieff, S., Guichard, B., Romet-Lemonne, G., & Jégou, A. (2020). Geometrical Constraints Greatly Hinder Formin mDia1 Activity. Nano Letters, 20(1), 22–32. https://doi.org/10.1021/acs.nanolett.9b02241
Kotila, T., Wioland, H., Enkavi, G., Kogan, K., Vattulainen, I., Jégou, A., Romet-Lemonne, G., & Lappalainen, P. (2019). Mechanism of synergistic actin filament pointed end depolymerization by cyclase-associated protein and cofilin. Nature Communications, 10(1), 5320. https://doi.org/10.1038/s41467-019-13213-2
Alieva, N. O., Efremov, A. K., Hu, S., Oh, D., Chen, Z., Natarajan, M., Ong, H. T., Jégou, A., Romet-Lemonne, G., Groves, J. T., Sheetz, M. P., Yan, J., & Bershadsky, A. D. (2019). Myosin IIA and formin dependent mechanosensitivity of filopodia adhesion. Nature Communications, 10(1), 3593. https://doi.org/10.1038/s41467-019-10964-w
Wioland, H., Jegou, A., & Romet-Lemonne, G. (2019). Torsional stress generated by ADF/cofilin on cross-linked actin filaments boosts their severing. Proceedings of the National Academy of Sciences of the United States of America, 116(7), 2595–2602. https://doi.org/10.1073/pnas.1812053116
Wioland, H., Jegou, A., & Romet-Lemonne, G. (2019). Quantitative Variations with pH of Actin Depolymerizing Factor/Cofilin’s Multiple Actions on Actin Filaments. Biochemistry, 58(1), 40–47. https://doi.org/10.1021/acs.biochem.8b01001
Cao, L., Kerleau, M., Suzuki, E. L., Wioland, H., Jouet, S., Guichard, B., Lenz, M., Romet-Lemonne, G., & Jegou, A. (2018). Modulation of formin processivity by profilin and mechanical tension. ELife, 7, e34176. https://doi.org/10.7554/eLife.34176
Wioland, H., Guichard, B., Senju, Y., Myram, S., Lappalainen, P., Jégou, A., & Romet-Lemonne, G. (2017). ADF/Cofilin Accelerates Actin Dynamics by Severing Filaments and Promoting Their Depolymerization at Both Ends. Current Biology: CB, 27(13), 1956-1967.e7. https://doi.org/10.1016/j.cub.2017.05.048
Frémont, S., Hammich, H., Bai, J., Wioland, H., Klinkert, K., Rocancourt, M., Kikuti, C., Stroebel, D., Romet-Lemonne, G., Pylypenko, O., Houdusse, A., & Echard, A. (2017). Oxidation of F-actin controls the terminal steps of cytokinesis. Nature Communications, 8(1), 14528. https://doi.org/10.1038/ncomms14528

Preprints

Park, Y., Leduc, C., Etienne-Manneville, S., & Portet, S. (2023). Models of Vimentin Organization Under Actin-Driven Transport (arXiv:2209.02780). arXiv. https://doi.org/10.48550/arXiv.2209.02780
Schahl, A., Lagardere, L., Walker, B., Ren, P., Jégou, A., Chavent, M., & Piquemal, J.-P. (2022). β-actin plasticity is modulated by coordinated actions of histidine 73 methylation, nucleotide type, and ions. bioRxiv. https://doi.org/10.1101/2022.12.16.520803
Morel, C., Lemerle, E., Tsai, F.-C., Obadia, T., Srivastava, N., Marechal, M., Salles, A., Albert, M., Stefani, C., Lamaze, C., Vassilopoulos, S., Piel, M., Bassereau, P., Gonzalez-Rodriguez, D., Leduc, C., & Lemichez, E. (2022). Caveolae govern plasma membrane mechanics to protect cells against EDIN B-induced transcellular tunnel formation and lethality from S. aureus septicaemia. bioRxiv. https://doi.org/10.1101/2022.09.27.509635
Cao, L., Ghasemi, F., Way, M., Jégou, A., & Romet-Lemonne, G. (2022). Nucleation and stability of branched versus linear Arp2/3-generated actin filaments. bioRxiv. https://doi.org/10.1101/2022.05.06.490861

Reviews

Wioland, H., Ghasemi, F., Chikireddy, J., Romet-Lemonne, G., & Jégou, A. (2022). Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles. Journal of Visualized Experiments: JoVE, 183. https://doi.org/10.3791/63891
Wioland, H., Jégou, A., & Romet-Lemonne, G. (2022). Celebrating 20 years of live single-actin-filament studies with five golden rules. Proceedings of the National Academy of Sciences of the United States of America, 119(3), e2109506119. https://doi.org/10.1073/pnas.2109506119
Romet-Lemonne, G., & Jégou, A. (2021). The dynamic instability of actin filament barbed ends. The Journal of Cell Biology, 220(4), e202102020. https://doi.org/10.1083/jcb.202102020
Jégou, A., & Romet-Lemonne, G. (2021). Mechanically tuning actin filaments to modulate the action of actin-binding proteins. Current Opinion in Cell Biology, 68, 72–80. https://doi.org/10.1016/j.ceb.2020.09.002
Jegou, A., & Romet-Lemonne, G. (2020). The many implications of actin filament helicity. Seminars in Cell & Developmental Biology, 102, 65–72. https://doi.org/10.1016/j.semcdb.2019.10.018
Romet-Lemonne, G., Guichard, B., & Jégou, A. (2018). Using Microfluidics Single Filament Assay to Study Formin Control of Actin Assembly. Methods in Molecular Biology (Clifton, N.J.), 1805, 75–92. https://doi.org/10.1007/978-1-4939-8556-2_4
Frémont, S., Romet-Lemonne, G., Houdusse, A., & Echard, A. (2017). Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis. Journal of Cell Science, 130(9), 1509–1517. https://doi.org/10.1242/jcs.202028

Foad GHASEMI : 2020-2023.

Léana LENGAGNE : 2021-2024

Jiu XIAO : 2021-2024

ANR, FRM, INSERM/ITMO, Labex WhoAmI?

4 postdoc positions opened