Poul Martin Bendix, Ph.D, Associate Professor

Professional Group Homepage click here Experimental Biophysics Research Group

My family name was "Hansen" until 06/2007

Person
Coordinates
e-mail:bendix@nbi.dk
Address: Blegdamsvej 17, Niels Bohr Institute, University of Copenhagen
phone: 35325251


Research Interests

Physics of the cell surface
We study physical processes of the cell surface like cell surface repair by annexins, filopodia dynamics and basic physical mechanisms by which proteins remodel the cell surface. This includes membrane-protein interactions with regard to membrane deformation or curvature sensing by both peripheral and transmembrane proteins. We study the effect of lipid order on the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity. These physical phenomena are also studied in plasma membranes isolated from living cells. This allows investigation of the membrane-protein interactions in a native membrane environment, but in absence of cytoskeletal elemements.

Physical tools to manipulate the cell surface
We use primarily optical techniques for shaping the plasma membrane. These include optically controlled thermoplasmonics for nanoscopic perturbation of the cell surface followed by investigation of cell surface repair. Thermoplasmonics is also used for direct fusion of membranes and cells. Optical trapping is used for quantitative measurements of cell surface activity like filopodia dynamics, but also for shaping the cell membrane for investigation of nanoscale membrane curvatures.

Effect of membrane curvature on lateral distribution of membrane proteins
Several membrane proteins exhibit interesting shapes that increases their preference for certain membrane curvatures. Both peripheral and transmembrane proteins are tested with respect to their affinity for a spectrum of high membrane curvatures. We generate high membrane curvatures by pulling membrane tubes out of Giant Unilamellar lipid Vesicles (GUVs). The tube diameter can be tuned by aspirating the GUV into a micropipette for controlling the membrane tension. By using fluorescently labled proteins we have shown that sorting of proteins like e.g. FBAR onto tubes is significantly increased for highly curved tubes (small tube diameter).

Previous Research

Membrane fusion
At Stanford University,
Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes.

Cytoskeletal dynamics
At Harvard University, Harvard soft matter group, I worked with reconstitutted contractile acto-myosin systems containing mainly actin, actin cross-linkers and myosin motors. Contractility and rheology of such systems was studied using confocal microscopy and rheology. Membrane adhesion and phase behavior
At the Nanoscience center KU I worked with adhesion of membranes to substrates using advances quantitative microscopy techniques. Also, I studied phase behavior of small unilamellar lipid vesicles with respect to their curvature.

CV

  • (2015-2019) Sapere Aude grant (Danish Council for Independent Research)
  • (2014-2016) Editorial board of Scientific Reports
  • (2012) Associated Professor at the Niels Bohr Institute
  • (2011) Assistant Professor at the Niels Bohr Institute
  • (2009-2010) Postdoc in "Boxer Lab" at Stanford University.
  • (2009) Postdoc at the Niels Bohr Institute at The University of Copenhagen.
  • (2007-2009) Postdoc at the Nanoscience Center at The University of Copenhagen.
  • (2007) Ph.D-degree in Biophysics at Niels Bohr Institute, University of Copenhagen.
  • (2006) Graduate student at Harvard University.
  • (2003) Cand. Scient. of physics at the University of Copenhagen.
  • (2001) Bachelor of physics and mathematics at the University of Copenhagen.

    Major Grants/Awards

  • (2019-2022) A Multidisciplinary Platform for Revealing Mechanisms of Annexin-mediated Plasma Membrane Repair Novo Synergy Programme (Co-applicant).
  • (2015-2019) Sapere Aude starting grant (Danish Council for Basic Research)
  • (2015-2018) Novo Synergy Programme (Co-applicant).
  • (2012-2015) Young Investigator Award (Villum Foundation)
  • Person

    "The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed."
    Albert Einstein

    Last updated Aug 2016