The microtubule nucleation capacity of the centrosome increases dramatically as cells progress from interphase into mitosis. The increase in nucleation capacity of the centrosome correlates with the cell cycle- dependent localization of the mitotic protein monoclonal-2 (MPM-2) phosphoepitope-specifc antibody to the mitotic centrosome. Therefore, the phosphorylation state of centrosomal components may regulate the microtubule nucleation capacity of this organelle during mitosis. Neither the identity of the MPM-2 kinase(s) nor all of the MPM-2-reactive phosphoproteins associated with the centrosome have been fully elucidated. Only recently have the characteristics of the MPM-2 epitope site been defined, and we used this information to prepare polyclonal antibodies against synthetic phosphopeptides containing potential MPM-2 epitopes derived from the sequences of two MPM-2-reactive proteins, topoisomerase II, and microtubule associated protein 1B (MAP1B). We demonstrate that these phosphopeptide- specific antibodies also localize to the centrosome in a cell cycle-dependent fashion. Thus, polyclonal antibodies have been generated against defined phosphopeptides that reiterate many of the immunofluorescence staining properties exhibited by the MPM-2 antibody. These new phosphopeptide-specific antibodies will provide additional probes to examine the phosphorylation of centrosomal components and the functional consequences of their phosphorylation during mitosis. (C) 2000 Wiley-Liss, Inc.
|Original language||English (US)|
|Number of pages||9|
|Journal||Microscopy Research and Technique|
|State||Published - Jun 1 2000|
All Science Journal Classification (ASJC) codes
- Medical Laboratory Technology