1. GTP-Specific Fab Fragment-Based GTPase Activity Assay.

    Analytical chemistry 87(6):3527 (2015) PMID 25707436

    GTPases are central cellular signaling proteins, which cycle between a GDP-bound inactive and a GTP-bound active conformation in a controlled manner. Ras GTPases are frequently mutated in cancer and so far only few experimental inhibitors exist. The most common methods for monitoring GTP hydroly...
  2. Rab-NANOPS: FRET Biosensors for Rab Membrane Nanoclustering and Prenylation Detection in Mammalian Cells.

    Methods in Molecular Biology 1298:29 (2015) PMID 25800830

    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. However, a number of diseases, including cancer, show a misregulation o...
  3. S-7 : A new cytokine receptor activation paradigm: Activation of JAK2 by the growth hormone receptor

    Cytokine 70(1):22 (2014)

    The conformational changes required to transmit the GH binding signal from the extracellular domain of the GH receptor to its intracellular domain resulting in activation of JAK2 has been enigmatic. We have recently defined the first complete mechanistic model for JAK2 activation based...
  4. RhoGDI facilitates geranylgeranyltransferase-I-mediated RhoA prenylation.

    Biochemical and Biophysical Research Communicat... 452(4):967 (2014) PMID 25223799

    Protein prenylation is a post-translational modification where farnesyl or geranylgeranyl groups are enzymatically attached to a C-terminal cysteine residue. This modification is essential for the activity of small cellular GTPases, as it allows them to associate with intracellular membranes. Di...
  5. RhoGDI facilitates geranylgeranyltransferase-I-mediated RhoA prenylation

    Biochemical and Biophysical Research Communicat... 452(4):967 (2014) PMID 25223799

    • We assessed the role of RhoGDI in GGTase-I-driven RhoA prenylation in vitro. • RhoGDI and GGTase-I operate sequentially during RhoA prenylation. ...
  6. Synthesis and characterization of novel phosphonocarboxylate inhibitors of RGGT.

    European Journal of Medicinal Chemistry 84:77 (2014) PMID 25016230

    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 synthe...
  7. Synthesis and characterization of novel phosphonocarboxylate inhibitors of RGGT

    European Journal of Medicinal Chemistry 84:77 (2014)

    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 ...
  8. Synthesis and characterization of novel phosphonocarboxylate inhibitors of RGGT.

    European Journal of Medicinal Chemistry 84:77 (2014) PMID 25016230

    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 synthe...
  9. Synthesis and characterization of novel phosphonocarboxylate inhibitors of RGGT.

    European Journal of Medicinal Chemistry 84:77 (2014) PMID 25016230

    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 synthe...
  10. A homogeneous quenching resonance energy transfer assay for H-Ras activation cycle monitoring and inhibitor screening

    New Biotechnology 31:S37 (2014)

  11. A homogeneous quenching resonance energy transfer assay for the kinetic analysis of the GTPase nucleotide exchange reaction.

    Analytical and Bioanalytical Chemistry 406(17):4147 (2014) PMID 24760397

    A quenching resonance energy transfer (QRET) assay for small GTPase nucleotide exchange kinetic monitoring is demonstrated using nanomolar protein concentrations. Small GTPases are central signaling proteins in all eukaryotic cells acting as a "molecular switches" that are active in the GTP-stat...
  12. A homogeneous quenching resonance energy transfer assay for H-Ras activation cycle monitoring and inhibitor screening

    New Biotechnology 31:S37 (2014)

  13. A homogeneous quenching resonance energy transfer assay for the kinetic analysis of the GTPase nucleotide exchange reaction.

    Analytical and Bioanalytical Chemistry 406(17):4147 (2014) PMID 24760397

    A quenching resonance energy transfer (QRET) assay for small GTPase nucleotide exchange kinetic monitoring is demonstrated using nanomolar protein concentrations. Small GTPases are central signaling proteins in all eukaryotic cells acting as a "molecular switches" that are active in the GTP-stat...
  14. Mechanism of activation of protein kinase JAK2 by the growth hormone receptor.

    Science 344(6185):1249783 (2014) PMID 24833397

    Signaling from JAK (Janus kinase) protein kinases to STAT (signal transducers and activators of transcription) transcription factors is key to many aspects of biology and medicine, yet the mechanism by which cytokine receptors initiate signaling is enigmatic. We present a complete mechanistic mo...
  15. The efficacy of Raf kinase recruitment to the GTPase H-ras depends on H-ras membrane conformer-specific nanoclustering.

    Journal of Biological Chemistry 289(14):9519 (2014) PMID 24569991 PMCID PMC3975003

    Solution structures and biochemical data have provided a wealth of mechanistic insight into Ras GTPases. However, information on how much the membrane organization of these lipid-modified proteins impacts on their signaling is still scarce. Ras proteins are organized into membrane nanoclusters, ...
  16. The efficacy of Raf kinase recruitment to the GTPase H-ras depends on H-ras membrane conformer-specific nanoclustering.

    Journal of Biological Chemistry 289(14):9519 (2014) PMID 24569991 PMCID PMC3975003

    Solution structures and biochemical data have provided a wealth of mechanistic insight into Ras GTPases. However, information on how much the membrane organization of these lipid-modified proteins impacts on their signaling is still scarce. Ras proteins are organized into membrane nanoclusters, ...
  17. The efficacy of Raf kinase recruitment to the GTPase H-ras depends on H-ras membrane conformer-specific nanoclustering.

    Journal of Biological Chemistry 289(14):9519 (2014) PMID 24569991 PMCID PMC3975003

    Solution structures and biochemical data have provided a wealth of mechanistic insight into Ras GTPases. However, information on how much the membrane organization of these lipid-modified proteins impacts on their signaling is still scarce. Ras proteins are organized into membrane nanoclusters, ...
  18. ColonyArea: an ImageJ plugin to automatically quantify colony formation in clonogenic assays.

    PLoS ONE 9(3):e92444 (2014) PMID 24647355 PMCID PMC3960247

    The clonogenic or colony formation assay is a widely used method to study the number and size of cancer cell colonies that remain after irradiation or cytotoxic agent administration and serves as a measure for the anti-proliferative effect of these treatments. Alternatively, this assay is used t...
  19. Nanoclustering and heterogeneous membrane diffusion of Ras studied by FRAP and RICS analysis.

    Methods in Molecular Biology 1120:307 (2014) PMID 24470034

    Fluorescence Recovery After Photobleaching (FRAP) and Raster Image Correlation Spectroscopy (RICS) are two powerful techniques to study the diffusion dynamics of fluorescently labeled proteins. FRAP and RICS can be easily applied on any commercial confocal microscope. In this chapter, we describ...
  20. Nanoclustering and heterogeneous membrane diffusion of Ras studied by FRAP and RICS analysis.

    Methods in Molecular Biology 1120:307 (2014) PMID 24470034

    Fluorescence Recovery After Photobleaching (FRAP) and Raster Image Correlation Spectroscopy (RICS) are two powerful techniques to study the diffusion dynamics of fluorescently labeled proteins. FRAP and RICS can be easily applied on any commercial confocal microscope. In this chapter, we describ...