Discrete nuclear structures in actively growing neuroblastoma cells are revealed by antibodies raised against phosphorylated neurofilament proteins

摘要: Background: Nuclear objects that have in common the property of being recognized by monoclonal antibodies specific for phosphoprotein epitopes and cytoplasmic intermediate filaments (in particular, SMI-31 RT-97) been reported glial neuronal cells, situ vitro. Since neurofilament are generally considered to be restricted cytoplasm, we were interested exploring identity structures labeled nucleus as well conditions under which they could found there. Results: Using confocal microscopy western analysis techniques, determined 1) immunolabeled truly within nucleus; 2) phosphoepitope RT-97 is not neurofilaments (NFs) it can identified on other filament proteins (IFs) cell types; 3) there a close relationship between DNA synthesis amount nuclear staining these thought proteins. Searches protein data bases putative phosphorylation motifs revealed lamins, NF-H, GFAP each contain single tyrosine motif with nearly identical amino acid sequence. Conclusion: We therefore suggest this sequence may epitope mABs, previously shown here likely phosphorylated lamin filaments, while labeling same mABs indicates NFs neurons or glia.