ABSTRACT
The growing problem of antibiotic resistance has been exacerbated by the use of new drugs that are merely variants of older overused antibiotics. While it is naive to expect to restrain the spread of resistance without controlling antibacterial usage, the desperate need for drugs with novel targets has been recognized by health organizations, industry and academia alike. The wealth of knowledge available about the bacterial cell-division pathway has aided target-driven approaches to identify novel inhibitors. Here, we discuss the therapeutic potential of inhibiting bacterial cell division, and review the progress made in this exciting new area of antibacterial discovery.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Cell Cycle Proteins/antagonists & inhibitors , Cell Division/drug effects , Drug Design , Drug Resistance, Bacterial/drug effects , Animals , Anti-Bacterial Agents/chemistry , HumansABSTRACT
The Bub1 kinase is a critical component of the spindle checkpoint involved in monitoring the separation of sister chromatids at mitosis. The viral oncoprotein Simian virus 40 large T antigen (LT) can bind and perturb the spindle checkpoint function of Bub1. We have developed three highly specific monoclonal antibodies against the Bub1 protein and have demonstrated that they can all detect Bub1 via Western blotting and immunofluorescence, in addition to their ability to immunoprecipitate Bub1.
Subject(s)
Antibodies, Monoclonal/biosynthesis , Cell Cycle Proteins/immunology , Protein Kinases/immunology , Amino Acid Motifs , Animals , Antibody Specificity , Antigens, Viral, Tumor/immunology , Cell Cycle Proteins/chemistry , Cell Cycle Proteins/genetics , Cell Line , Hybridomas/immunology , Mice , Microscopy, Fluorescence , NIH 3T3 Cells , Protein Kinases/chemistry , Protein Kinases/genetics , Protein Serine-Threonine Kinases , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunologyABSTRACT
The mitotic spindle checkpoint protein Bub1 has been found to be mutated at low frequency in certain human cancers characterized by aneuploidy. Simian virus 40 large T antigen efficiently immortalizes rodent cells and occasionally transforms them to tumorigenicity. T antigen can also cause genomic instability, inducing chromosomal aberrations and aneuploidy. Here, we report an interaction between Bub1 and T antigen. T antigen coimmunoprecipitates with endogenous Bub1 and Bub3, another component of the spindle checkpoint complex. Genetic analysis demonstrates that the interaction of T antigen with Bub1 is not required for immortalization but is closely correlated with transformation. T antigen induces an override of the spindle checkpoint dependent on Bub1 binding. This interaction with proteins of the spindle checkpoint machinery suggests another role for T antigen and provides insight into its ability to cause chromosomal aberrations, aneuploidy, and transformation.
