Spontaneous Formation and Rearrangement of Artificial Lipid Nanotube Networks as a Bottom-Up Model for Endoplasmic Reticulum
Journal article, 2019

We present a convenient method to form a bottom-up structural organelle model for the endoplasmic reticulum (ER). The model consists of highly dense lipidic nanotubes that are, in terms of morphology and dynamics, reminiscent of ER. The networks are derived from phospholipid double bilayer membrane patches adhering to a transparent Al2O3 substrate. The adhesion is mediated by Ca2+ in the ambient buffer. Subsequent depletion of Ca2+ by means of BAPTA/EDTA causes retraction of the membrane, resulting in spontaneous lipid nanotube network formation. The method only comprises phospholipids and microfabricated surfaces for simple formation of an ER model and does not require the addition of proteins or chemical energy (e.g., GTP or ATP). In contrast to the 3D morphology of the cellular endoplasmic reticulum, the model is two-dimensional (albeit the nanotube dimensions, geometry, structure, and dynamics are maintained). This unique in vitro ER model consists of only a few components, is easy to construct, and can be observed under a light microscope. The resulting structure can be further decorated for additional functionality, such as the addition of ER-associated proteins or particles to study transport phenomena among the tubes. The artificial networks described here are suitable structural models for the cellular ER, whose unique characteristic morphology has been shown to be related to its biological function, whereas details regarding formation of the tubular domain and rearrangements within are still not completely understood. We note that this method uses Al2O3 thin-film-coated microscopy coverslips, which are commercially available but require special orders. Therefore, it is advisable to have access to a microfabrication facility for preparation.

Bioengineering

phospholipid nanotube

lipid nanotube network

thin film deposition

Issue 143

double lipid bilayer

Endoplasmic reticulum

aluminum oxide

Author

Elif Senem Koksal

University of Oslo

Patricia F. Belletati

University of Oslo

Ganna Reint

University of Oslo

Ragni Olsson

University of Oslo

Kira D. Leitl

University of Oslo

Ilayda Kantarci

University of Oslo

Irep Gözen

University of Oslo

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Journal of Visualized Experiments

1940-087X (ISSN)

Vol. 2019 143 e58923

Bristande biomembran: ett fokus på grundläggande forskning, materialvetenskap, nanoteknik och hälsa

Swedish Research Council (VR), 2016-01-01 -- 2019-12-31.

Subject Categories

Physical Chemistry

Biochemistry and Molecular Biology

Biophysics

PubMed

30735173

More information

Latest update

7/15/2019