title: Isoform-specific cleavage of 14-3-3 proteins in apoptotic JURL-MK1 cells.
abstract: The proteins of 14-3-3 family are substantially involved in the regulation of many biological processes including the apoptosis. We studied the changes in the expression of five 14-3-3 isoforms (beta, gamma, epsilon, tau, and zeta) during the apoptosis of JURL-MK1 and K562 cells. The expression level of all these proteins markedly decreased in relation with the apoptosis progression and all isoforms underwent truncation, which probably corresponds to the removal of several C-terminal amino acids. The observed 14-3-3 modifications were partially blocked by caspase-3 inhibition. In addition to caspases, a non-caspase protease is likely to contribute to 14-3-3's cleavage in an isoform-specific manner. While 14-3-3 gamma seems to be cleaved mainly by caspase-3, the alternative mechanism is essentially involved in the case of 14-3-3 tau, and a combined effect was observed for the isoforms epsilon, beta, and zeta. We suggest that the processing of 14-3-3 proteins could form an integral part of the programmed cell death or at least of some apoptotic pathways.
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague 2, Czech Republic. kuzel@uhkt.cz
authors.forename: Katerina
authors.initials: K
authors.lastname: Kuzelová
authors.forename: Dana
authors.initials: D
authors.lastname: Grebenová
authors.forename: Michaela
authors.initials: M
authors.lastname: Pluskalová
authors.forename: Daniel
authors.initials: D
authors.lastname: Kavan
authors.forename: Petr
authors.initials: P
authors.lastname: Halada
authors.forename: Zbynek
authors.initials: Z
authors.lastname: Hrkal
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism*; D017209:Apoptosis; D053148:Caspase 3; D045744:Cell Line, Tumor; D005786:Gene Expression Regulation; D006801:Humans; D006868:Hydrolysis; D020014:K562 Cells; D010447:Peptide Hydrolases / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism
chemical_list: D048948:14-3-3 Proteins; D020033:Protein Isoforms; D010447:Peptide Hydrolases; D053148:Caspase 3