Detection of Ras nanoclustering-dependent homo-FRET using fluorescence anisotropy measurements.

The small GTPase Ras is frequently mutated in cancer and a driver of tumorigenesis. The recent years have shown great progress in drug-targeting Ras and understanding how it operates on the plasma membrane. We now know that Ras is non-randomly organized into proteo-lipid complexes on the membrane, called nanoclusters.

Rab-NANOPS: FRET biosensors for Rab membrane nanoclustering and prenylation detection in mammalian cells.

Rab proteins constitute the largest subfamily of Ras-like small GTPases. They are central to vesicular transport and organelle definition in eukaryotic cells. Unlike their Ras counterparts, they are not a hallmark of cancer.

Synthesis and characterization of novel phosphonocarboxylate inhibitors of RGGT.

Phosphonocarboxylate (PC) analogs of the anti-osteoporotic drugs, bisphosphonates, represent the first class of selective inhibitors of Rab geranylgeranyl transferase (RabGGTase, RGGT), an enzyme implicated in several diseases including ovarian, breast and skin cancer. Here we present the synthesis and biological characterization of an extended set of this class of compounds, including lipophilic derivatives of the known RGGT inhibitors. From this new panel of PCs, we have identified an inhibitor of RGGT that is of similar potency as the most active published phosphonocarboxylate, but of higher selectivity towards this enzyme compared to prenyl pyrophosphate synthases.

Cellular FRET-Biosensors to Detect Membrane Targeting Inhibitors of N-Myristoylated Proteins.

Hundreds of eukaryotic signaling proteins require myristoylation to functionally associate with intracellular membranes. N-myristoyl transferases (NMT) responsible for this modification are established drug targets in cancer and infectious diseases. Here we describe NANOMS (NANOclustering and Myristoylation Sensors), biosensors that exploit the FRET resulting from plasma membrane nanoclustering of myristoylated membrane targeting sequences of Gαi2, Yes- or Src-kinases fused to fluorescent proteins.

Receptor tyrosine kinase transmembrane domain interactions: potential target for "interceptor" therapy.

Signaling by receptor tyrosine kinases (RTKs) involves ligand-induced dimerization of receptors within the plasma membrane, triggering subsequent downstream signaling events. Although the transmembrane domains play an important role in dimerization, the importance of their interactions in transmembrane signaling is not clearly understood. Here, I highlight recent research that describes the intrinsic propensity of the single transmembrane domains of all 58 human RTKs to self-interact and suggest that these interactions could be exploited for designing peptides to inhibit signaling through these receptors.