ABSTRACT
We describe a lanthanide biosensor that responds to CDK4 kinase activity in melanoma cell extracts through a significant and dose dependent increase in luminescence, thanks to sensitization of a DOTA[Tb3+] complex incorporated into a CDK4 substrate peptide by a unique tryptophan residue in an adjacent phosphoaminoacid binding moiety.
Subject(s)
Coordination Complexes/chemistry , Cyclin-Dependent Kinase 4/analysis , Fluorescent Dyes/metabolism , Heterocyclic Compounds, 1-Ring/chemistry , Peptides/metabolism , Aminopyridines/pharmacology , Benzimidazoles/pharmacology , Binding Sites , Biosensing Techniques/methods , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Cyclin-Dependent Kinase 4/antagonists & inhibitors , Cyclin-Dependent Kinase 4/metabolism , Fluorescence , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/chemistry , Heterocyclic Compounds, 1-Ring/chemical synthesis , Humans , Peptides/chemical synthesis , Peptides/chemistry , Phosphorylation , Purines/pharmacology , Roscovitine , Terbium/chemistry , Tryptophan/chemistryABSTRACT
Connexins (Cxs) are integral membrane proteins that form high-conductance plasma membrane channels, allowing communication from cell to cell (via gap junctions) and from cells to the extracellular environment (via hemichannels). Initially described for their role in joining excitable cells (nerve and muscle), gap junctions (GJs) are found between virtually all cells in solid tissues and are essential for functional coordination by enabling the direct transfer of small signalling molecules, metabolites, ions, and electrical signals from cell to cell. Several studies have revealed diverse channel-independent functions of Cxs, which include the control of cell growth and tumourigenicity. Connexin43 (Cx43) is the most widespread Cx in the human body. The myriad roles of Cx43 and its implication in the development of disorders such as cancer, inflammation, osteoarthritis and Alzheimer's disease have given rise to many novel questions. Several RNA- and DNA-binding motifs were predicted in the Cx43 and Cx26 sequences using different computational methods. This review provides insights into new, ground-breaking functions of Cxs, highlighting important areas for future work such as transfer of genetic information through extracellular vesicles. We discuss the implication of potential RNA- and DNA-binding domains in the Cx43 and Cx26 sequences in the cellular communication and control of signalling pathways.
Subject(s)
Cell-Derived Microparticles/metabolism , Connexin 43/metabolism , Connexins/metabolism , Exosomes/metabolism , Protein Interaction Domains and Motifs , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Animals , Biological Transport , Cell Communication , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Connexin 26 , Connexin 43/genetics , Connexins/genetics , Gap Junctions , Humans , Inflammation , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/pathology , Osteoarthritis/genetics , Osteoarthritis/metabolism , Osteoarthritis/pathology , RNA/genetics , RNA/metabolismABSTRACT
We report a light-sensitive histidine building block for Fmoc/tBu solid-phase peptide synthesis in which the imidazole side chain is coordinated to a ruthenium complex. We have applied this building block for the synthesis of caged-histidine peptides that can be readily deprotected by irradiation with visible light, and demonstrated the application of this approach for the photocontrol of the activity of Ni(II)-dependent peptide nucleases.
Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Histidine/chemistry , Light , Organometallic Compounds/chemistry , Peptides/chemistry , Peptides/chemical synthesis , Photolysis/radiation effects , 2,2'-Dipyridyl/chemistry , Molecular Structure , Peptides/radiation effectsABSTRACT
A new 4-(N,N-dimethylamino) phthalimide-based environment-sensitive fluorescent building block for solid phase peptide synthesis, has been synthesized and incorporated into peptides. Peptides incorporating this residue show great potential for biological applications in sensing protein/protein interactions.
