Nanotechnology meets cell biology: the role of cellular membrane shape in hormone secretion

Purpose and goal

Throughout the process of insulin secretion, the shape of the membranes change dramatically, but no methods exist for quantitatively studying membrane shape and protein interactions in live cells. To develop new methodology in this interdisciplinary project we had two main objectives: 1) To develop substrates for cellular growth that introduce membrane curvature into cells and 2) To assess how docking of insulin containing vesicles and the recruitment of fusion proteins are affected by the newly introduced regions of membrane curvature.

Expected results and effects

The results of this work led to the design of novel methods for the nanofabrication of glass substrates. The electron beam lithography process of nanofabrication designed here yields substrates that are useful for imaging cell membranes with total internal reflection fluorescence microscopy, a common tool of cell biology. Finally, using these substrates, insulin secreting cells were cultured with fluorescently labeled insulin granules and SNARE proteins to address the role of membrane curvature in insulin secretion.

Planned approach and implementation

The experimental design involved patterning substrates for cellular growth. Once insulin secreting cells were grown on substrates, quantitative microscopy methods were used to determine if the cell conforms around the substrate. Ultimately, protein organization will be quantified. Funding from Vinnova also affected the mobility of the researcher. The researcher connected with Swedish scientists at Uppsala Univeritet, Stockholm Universitet and Lund Universitet with the purpose of establishing future collaborations in grant applications and student exchange.