Proximity ligation assay are used to detect single molecules
Methods to study posttranslational modifications and protein interactions are essential to determine the activity status of signaling cascades in a cell. To be able to examine mixed cell populations and to study cell communication the analyses need to be performed at a single cell level.
We therefore developed a method for detection of PTM and protein interactions with a single molecule resolution, using microscopy for read-out. The method is called proximity ligation assay (PLA) and includes the recognition of a molecule or complex by two antibodies that are linked to short DNA strands. When the antibodies have bound a circular DNA molecule can be formed, which subsequently can be used to produce a detectable signal. The main advantage with this method is that it can be applied on tissues and cells in clinical specimens, which makes it useful for diagnostic applications.
The aim with our research is to identify the signals governing the growth and survival of cancer cells, by developing a panel of assays, to be used as diagnostic and predictive tools. This knowledge will also be used to develop new therapies to selectively target the PTM and protein interactions that are essential for the tumor cells.
You can read more about our methods at: http://www.igp.uu.se/research/molecular_tools/ola_soderberg/?languageId=1