Micropatterned model biological membrane - Dr Kenichi Morigaki, KU, Japan

Dr Kenichi Morigaki, of the Dept of Agrobioscience, Kobe University, Japan, will be presenting a seminar on his research.

Micropatterned model biological membrane: Potentials for biophysical studies and biomedical applications Abstract: We developed a micropatterned model biological membrane on a solid substrate by combining polymeric and fluid lipid bilayers. A patterned polymeric bilayer was lithographically generated from diacetylene phospholipid by UV irradiation. Fluid bilayers composed of natural lipids were successively incorporated into the polymer-free regions. The polymeric lipid bilayer acted as a stable framework and the embedded fluid lipid bilayers mimicked the lateral mobility and two-dimensional organization of the biological membrane. Membrane proteins involved in the photo-signal transduction (e.g. rhodopsin) were reconstituted and their affinities of to lipid rafts were evaluated (1).

We also succeeded in reconstituting thylakoid membrane from chloroplast in plant cells into the patterned matrix to form a continuous two-dimensional membrane. The reconstituted thylakoid membrane retains the electron transfer activities and serves as an experimental platform to study the molecular machinery of photosynthesis. In addition to the two-dimensional membrane structures, we design a three-dimensional structure composed of a patterned membrane and a nanometric gap structure (nanogap-junction) as a selective and sensitive biosensing platform (2-3).

To this end, the polymeric bilayer was bonded with a polydimetylsiloxan (PDMS) sheet via an adhesion layer having a defined thickness (lipid vesicles and silica nanoparticles). Membrane-bound proteins are selectively transported into the nanogap-junction by the lateral diffusion and detected with an elevated signal-to-noise-ratio. Patterned model membranes with controlled two-dimensional and three-dimensional architectures provide a versatile platform not only for the basic membrane biophysics but also for the biomedical applications, including biosensors, bioassays, and cell culture.

1. Tanimoto, Y., Okada, K., Hayashi, F., Morigaki, K. "Evaluating the raftophilicity of rhodopsin photoreceptor in a patterned model membrane", Biophys. J. 109, 2307-2316, (2015)

2. Ando, K., Tanabe, M., Morigaki, K. "Nanometric gap structure with fluid lipid bilayer for the selective transport and detection of biological molecules", Langmuir 32, 7958-7964, (2016)

3. Tanabe, M., Ando, K., Morigaki, K. "Nanofluidic biosensor created by bonding patterned model cell membrane and silicone elastomer with silica nanoparticles", Small 14 1802804, (2018)

Host: Dr Peter Adams

All are welcome to attend.