VDAC1 sequences and amino acid residues important for interaction with Bcl-2 were defined through
site-directed mutagenesis. Synthetic peptides corresponding to the VDAC1 N-terminal region and selected sequences bound specifically, TH-302 price in a concentration-and time-dependent manner, to immobilized Bcl-2, as revealed by the real-time surface plasmon resonance. Moreover, expression of the VDAC1-based peptides in cells over-expressing Bcl-2 prevented Bcl-2-mediated protection against staurosporine-induced apoptotic cell death. Similarly, a cell-permeable VDAC1-based synthetic peptide was also found to prevent Bcl-2-GFP-mediated protection against apoptosis. These results point to Bcl-2 as promoting tumor cell survival through binding to VDAC1, thereby inhibiting cytochrome c release and apoptotic cell death. Moreover, these findings suggest that interfering with the binding of Bcl-2 to mitochondria by VDAC1-based peptides
may serve to potentiate the efficacy of conventional chemotherapeutic agents.”
“Chromosome region maintenance 1/exportin1/Exp1/Xpo1 (CRM1) is the major transport receptor for the export of proteins from the nucleus. It binds to nuclear export signals (NESs) that are rich in leucines and other hydrophobic amino acids. The prediction of NESs is difficult because of the extreme recognition flexibility buy CP-868596 of CRM1. Furthermore, proteins can be exported upon binding to an NES-containing adaptor protein. Here we present check details an approach for identifying targets of the CRM1-export pathway via quantitative mass spectrometry using stable isotope labeling with amino acids in cell culture. With this approach, we identified >100 proteins from HeLa cells that were depleted from cytosolic fractions and/or enriched in nuclear
fractions in the presence of the selective CRM1-inhibitor leptomycin B. Novel and validated substrates are the polyubiquitin-binding protein sequestosome 1, the cancerous inhibitor of protein phosphatase 2A (PP2A), the guanine nucleotide-binding protein-like 3-like protein, the programmed cell death protein 2-like protein, and the cytosolic carboxypeptidase 1 (CCP1). We identified a functional NES in CCP1 that mediates direct binding to the export receptor CRM1. The method will be applicable to other nucleocytoplasmic transport pathways, as well as to the analysis of nucleocytoplasmic shuttling proteins under different growth conditions. Molecular & Cellular Proteomics 12: 10.1074/mcp.M112.024877, 664-678, 2013.”
“With the rise in methamphetamine (MA) use among women of childbearing age, the potential consequences of MA exposure to the developing brain for cognition in adulthood is a major concern. Histamine might mediate these MA effects. Following MA administration in neonatal mice, histamine levels in brain were elevated and the hypothalamic-pituitary-adrenal axis was activated. Co-administration of MA with the H3 receptor agonist immepip antagonized these effects.