Nitric oxide modulates chromatin folding in human endothelial cells via protein phosphatase 2A activation and class II histone deacetylases nuclear shuttling.
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.
Illi
Barbara
B
Laboratorio di Biologia Vascolare e Terapia Genica, Centro Cardiologico Fondazione I. Monzino, IRCCS, Milan, Italy. b.illi@idi.it
Dello Russo
Claudio
C
Colussi
Claudia
C
Rosati
Jessica
J
Pallaoro
Michele
M
Spallotta
Francesco
F
Rotili
Dante
D
Valente
Sergio
S
Ragone
Gianluca
G
Martelli
Fabio
F
Biglioli
Paolo
P
Steinkuhler
Christian
C
Gallinari
Paola
P
Mai
Antonello
A
Capogrossi
Maurizio C
MC
Gaetano
Carlo
C
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
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