Approved FOM programme
|Title||Single gold nanorods in live cells (SGC)|
|Executive organisational unit||BUW|
|Programme management||Dr.ir. S.J.T. van Noort|
|Cost estimate||M€ 1.4|
The aim of this programme is to develop the methodology to probe the function and mechanics of a wide range of biomolecules in a living cell. We will use a single gold nanorod as a probe for tracking and force/torque transduction on single molecules. Kros will synthesize gold nanorods with a surface chemistry that allows us to incorporate a specific functionality onto the probe and to control conjugation with selected proteins inside the cell, that are genetically tagged by Schaaf. Tagged proteins will be followed in three dimensions for arbitrarily long times using the two-photon microscope and tracking algorithms developed by Van Noort. Orrit will further develop the optical trapping and manipulation of a single gold nanorod in vitro.
We will use this new technology to study and develop delivery strategies for nanorods into the cell, to optimize detection and manipulation techniques for chromatin biophysics in vitro, to reveal the mechanisms of glucocorticoid receptor (GR) based regulation in vivo and to probe chromatin organization in vivo.
Background, relevance and implementation
Single-molecule fluorescence and force spectroscopy provide novel insight into the dynamics and interactions of biomolecules. Yet, current in vitro experiments are not always relevant to complex and variable cell conditions. Tracking and manipulating single molecules inside a cell is still not possible because (1) current fluorescent labels exhibit poor optical stability and (2) the bulky microbeads employed in optical or magnetic tweezers easily interfere with cell function.
We will employ gold nanorods as a solution to both these issues. Recently we have developed methods to track and trap single gold nanorods in vitro, and in this programme we will advance these methods further to probe specific biomolecules inside a cell. Because gold nanorods don't blink or bleach we can follow a labeled biomolecule for arbitrary long times. Moreover, their small volume (comparable to a big protein complex) warrants a significantly reduced invasiveness compared to microbeads generally used for force spectroscopy. Being small, they are also less prone to undesired non-specific interactions with cell components.
Our consortium will use the physical knowledge on microscopy and force spectroscopy, chemical knowledge on the synthesis and functionalization of gold nanoparticles, as well as specific biological knowledge to address the glucocorticoid signaling pathway. All participants are located in one building, ensuring a close and efficient collaboration. By joining the expertise from such diverse disciplines we will be able to address one of the most pertinent challenges in biophysics and cell biology i.e. tracking and manipulating the journey of individual molecules through the cell.
The final evaluation of this programme will consist of a self-evaluation initiated by the programme leader and is foreseen for 2017.
Please find a research highlight that was achieved in 2013 within this FOM programme here.