title: Nitric oxide modulates chromatin folding in human endothelial cells via protein phosphatase 2A activation and class II histone deacetylases nuclear shuttling.
abstract: Nitric oxide (NO) modulates important endothelial cell (EC) functions and gene expression by a molecular mechanism which is still poorly characterized. Here we show that in human umbilical vein ECs (HUVECs) NO inhibited serum-induced histone acetylation and enhanced histone deacetylase (HDAC) activity. By immunofluorescence and Western blot analyses it was found that NO induced class II HDAC4 and 5 nuclear shuttling and that class II HDACs selective inhibitor MC1568 rescued serum-dependent histone acetylation above control level in NO-treated HUVECs. In contrast, class I HDACs inhibitor MS27-275 had no effect, indicating a specific role for class II HDACs in NO-dependent histone deacetylation. In addition, it was found that NO ability to induce HDAC4 and HDAC5 nuclear shuttling involved the activation of the protein phosphatase 2A (PP2A). In fact, HDAC4 nuclear translocation was impaired in ECs expressing small-t antigen and exposed to NO. Finally, in cells engineered to express a HDAC4-Flag fusion protein, NO induced the formation of a macromolecular complex including HDAC4, HDAC3, HDAC5, and an active PP2A. The present results show that NO-dependent PP2A activation plays a key role in class II HDACs nuclear translocation.
authors.affiliation: Laboratorio di Biologia Vascolare e Terapia Genica, Centro Cardiologico Fondazione I. Monzino, IRCCS, Milan, Italy. b.illi@idi.it
authors.forename: Barbara
authors.initials: B
authors.lastname: Illi
authors.forename: Claudio
authors.initials: C
authors.lastname: Dello Russo
authors.forename: Claudia
authors.initials: C
authors.lastname: Colussi
authors.forename: Jessica
authors.initials: J
authors.lastname: Rosati
authors.forename: Michele
authors.initials: M
authors.lastname: Pallaoro
authors.forename: Francesco
authors.initials: F
authors.lastname: Spallotta
authors.forename: Dante
authors.initials: D
authors.lastname: Rotili
authors.forename: Sergio
authors.initials: S
authors.lastname: Valente
authors.forename: Gianluca
authors.initials: G
authors.lastname: Ragone
authors.forename: Fabio
authors.initials: F
authors.lastname: Martelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Biglioli
authors.forename: Christian
authors.initials: C
authors.lastname: Steinkuhler
authors.forename: Paola
authors.initials: P
authors.lastname: Gallinari
authors.forename: Antonello
authors.initials: A
authors.lastname: Mai
authors.forename: Maurizio C
authors.initials: MC
authors.lastname: Capogrossi
authors.forename: Carlo
authors.initials: C
authors.lastname: Gaetano
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects*; D002478:Cells, Cultured; D042002:Chromatin Assembly and Disassembly; D042783:Endothelial Cells / Q000201:enzymology / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology*; D004789:Enzyme Activation; D006655:Histone Deacetylases / Q000378:metabolism*; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology*; D046912:Multiprotein Complexes; D009569:Nitric Oxide / Q000494:pharmacology*; D054648:Protein Phosphatase 2 / Q000378:metabolism*; D011758:Pyrroles / Q000494:pharmacology*; D012097:Repressor Proteins / Q000378:metabolism; D014471:Umbilical Veins; D000099186:Histone Deacetylase 3
chemical_list: D006655:Histone Deacetylases; D006877:Hydroxamic Acids; D046912:Multiprotein Complexes; D009569:Nitric Oxide; D054648:Protein Phosphatase 2; D011758:Pyrroles; D012097:Repressor Proteins; D000099186:Histone Deacetylase 3; C577554:MC1568; C400300:HDAC4 protein, human; C404500:HDAC5 protein, human