TY - JOUR
T1 - Nuclear factor κB mediates suppression of canonical transient receptor potential 6 expression by reactive oxygen species and protein kinase C in kidney cells
AU - Wang, Yanxia
AU - Ding, Min
AU - Chaudhari, Sarika
AU - Ding, Yanfeng
AU - Yuan, Joseph
AU - Stankowska, Dorota
AU - He, Shaoqing
AU - Krishnamoorthy, Raghu
AU - Cunningham, Joseph T.
AU - Ma, Rong
PY - 2013/5/3
Y1 - 2013/5/3
N2 - This study was carried out to explore the molecular mechanism for down-regulation of TRPC6 expression in the reactive oxygen species (ROS)/PKC signaling in kidney cells. In cultured human mesangial cells, H 2O2 and TNF-α inhibited TRPC6 mRNA expression in a time-dependent manner. Inhibition of NF-κB reversed both H 2O2- and phorbol 12-myristate 13-acetate (PMA)-induced decrease in TRPC6 protein expression. Activation of NF-κB by knocking down IκBα using siRNA could mimic the suppressive effect of ROS/PKC on TRPC6. a Ca2+ imaging study showed that activation and inhibition of NF-κB significantly decreased and increased the TRPC6-mediated Ca 2+ entry, respectively. Further experiments showed that PMA, but not its inactive analog 4α-phorbol 12, 13-didecanoate (4α-PDD), caused phosphorylation of IκBα and stimulated the nuclear translocation of NF-κB p50 and p65 subunits. The PMA-dependent IκBα phosphorylation was significantly inhibited by Gö6976. Electrophoretic mobility shift assay revealed that PMA stimulated DNA binding activity of NF-κB. Furthermore, specific knockdown of p65, but not p50, prevented an H2O2 inhibitory effect onTRPC6protein expression, suggesting p65 as a predominant NF-κB subunit repressing TRPC6. In agreement with a major role of p65, chromatin immunoprecipitation assays showed that PMA treatment induced p65 binding to the TRPC6 promoter. Moreover, PMA treatment increased the association of p65 with histone deacetylase (HDAC) and decreased histone acetylation at the TRPC6 promoter. Consistently, knockdown of HDAC2 by siRNA or inhibition of HDAC with trichostatin A prevented a H 2O2-induced decrease in TRPC6 mRNA and protein expressions, respectively. Taken together, our findings imply an important role of NF-κB in a negative regulation of TRPC6 expression at the gene transcription level in kidney cells.
AB - This study was carried out to explore the molecular mechanism for down-regulation of TRPC6 expression in the reactive oxygen species (ROS)/PKC signaling in kidney cells. In cultured human mesangial cells, H 2O2 and TNF-α inhibited TRPC6 mRNA expression in a time-dependent manner. Inhibition of NF-κB reversed both H 2O2- and phorbol 12-myristate 13-acetate (PMA)-induced decrease in TRPC6 protein expression. Activation of NF-κB by knocking down IκBα using siRNA could mimic the suppressive effect of ROS/PKC on TRPC6. a Ca2+ imaging study showed that activation and inhibition of NF-κB significantly decreased and increased the TRPC6-mediated Ca 2+ entry, respectively. Further experiments showed that PMA, but not its inactive analog 4α-phorbol 12, 13-didecanoate (4α-PDD), caused phosphorylation of IκBα and stimulated the nuclear translocation of NF-κB p50 and p65 subunits. The PMA-dependent IκBα phosphorylation was significantly inhibited by Gö6976. Electrophoretic mobility shift assay revealed that PMA stimulated DNA binding activity of NF-κB. Furthermore, specific knockdown of p65, but not p50, prevented an H2O2 inhibitory effect onTRPC6protein expression, suggesting p65 as a predominant NF-κB subunit repressing TRPC6. In agreement with a major role of p65, chromatin immunoprecipitation assays showed that PMA treatment induced p65 binding to the TRPC6 promoter. Moreover, PMA treatment increased the association of p65 with histone deacetylase (HDAC) and decreased histone acetylation at the TRPC6 promoter. Consistently, knockdown of HDAC2 by siRNA or inhibition of HDAC with trichostatin A prevented a H 2O2-induced decrease in TRPC6 mRNA and protein expressions, respectively. Taken together, our findings imply an important role of NF-κB in a negative regulation of TRPC6 expression at the gene transcription level in kidney cells.
UR - http://www.scopus.com/inward/record.url?scp=84877125730&partnerID=8YFLogxK
U2 - 10.1074/jbc.M112.410357
DO - 10.1074/jbc.M112.410357
M3 - Article
C2 - 23525112
AN - SCOPUS:84877125730
VL - 288
SP - 12852
EP - 12865
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 18
ER -