title: Evidence for p62 aggregate formation: role in cell survival.
abstract: The polyubiquitin-binding protein p62 has been shown to localize in aggregates common to several types of diseases. Here, we report that p62 forms independent fibrillar aggregates in vitro in a time- and concentration-dependent manner. FTIR spectra and ThT fluorescence assay of p62 reveals increased beta-sheet content as aggregates form compared to the native protein. The fibrillar nature of the aggregates was observed by transmission electron microscopy. Overexpression of p62 in HEK cells results in aggregate formation that may protect cells from apoptosis. Altogether, these results suggest that p62 fibrils may influence cell viability and indicates an important role for p62 in aggresome formation.
authors.affiliation: Program in Cell and Molecular Biosciences, Auburn University, AL 36849, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Paine
authors.forename: J Ramesh
authors.initials: JR
authors.lastname: Babu
authors.forename: M Lamar
authors.initials: ML
authors.lastname: Seibenhener
authors.forename: Marie W
authors.initials: MW
authors.lastname: Wooten
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D002460:Cell Line; D002470:Cell Survival; D006801:Humans; D046912:Multiprotein Complexes / Q000648:ultrastructure; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000071456:Sequestosome-1 Protein; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D046912:Multiprotein Complexes; D011506:Proteins; D011993:Recombinant Fusion Proteins; C099718:SQSTM1 protein, human; D000071456:Sequestosome-1 Protein