TY - JOUR
T1 - Dex-ras1 and serum- and glucocorticoid-inducible protein kinase 1: Regulation of expression by dexamethasone in HEK293 cells
AU - Attarzadeh-Yazdi, G.
AU - Shipston, M. J.
AU - Antoni, F. A.
PY - 2008/4
Y1 - 2008/4
N2 - The molecular and cellular basis of the psychotropic actions of adrenal corticosteroids is poorly understood. Previously, we reported that modulation of large conductance Ca2+-activated potassium channel (BK-channel) function by glucocorticoids can be recapitulated in human embryonic kidney293 (HEK293) cells (J Physiol 537:57, 2001). In the present paper, we examined the effect of dexamethasone on the expression of candidate mediator proteins of glucocorticoid action, dex-ras1 and serum and glucocorticoid inducible protein kinase 1 (SGK), in HEK293 cells. Dex-ras1 mRNA was readily detectable under basal conditions however, no changes of dex-ras1 mRNA expression occurred upon exposure to 100 nM of dexamethasone for 2 h. In contrast, a 2.5-fold increase of SGK mRNA was found under similar conditions. Total levels of cellular SGK protein were unaltered upon exposure to dexamethasone, but a marked increase of SGK in a Triton-X100 insoluble fraction was observed. BK-channel α-subunits could not be co-immunoprecipitated with SGK. In summary, SGK, but not dex-ras1, mRNA is rapidly induced by glucocorticoid stimulation in HEK293 cells. However, there appears to be no direct protein-protein interaction between SGK and BK-channel α-subunits.
AB - The molecular and cellular basis of the psychotropic actions of adrenal corticosteroids is poorly understood. Previously, we reported that modulation of large conductance Ca2+-activated potassium channel (BK-channel) function by glucocorticoids can be recapitulated in human embryonic kidney293 (HEK293) cells (J Physiol 537:57, 2001). In the present paper, we examined the effect of dexamethasone on the expression of candidate mediator proteins of glucocorticoid action, dex-ras1 and serum and glucocorticoid inducible protein kinase 1 (SGK), in HEK293 cells. Dex-ras1 mRNA was readily detectable under basal conditions however, no changes of dex-ras1 mRNA expression occurred upon exposure to 100 nM of dexamethasone for 2 h. In contrast, a 2.5-fold increase of SGK mRNA was found under similar conditions. Total levels of cellular SGK protein were unaltered upon exposure to dexamethasone, but a marked increase of SGK in a Triton-X100 insoluble fraction was observed. BK-channel α-subunits could not be co-immunoprecipitated with SGK. In summary, SGK, but not dex-ras1, mRNA is rapidly induced by glucocorticoid stimulation in HEK293 cells. However, there appears to be no direct protein-protein interaction between SGK and BK-channel α-subunits.
UR - http://www.scopus.com/inward/record.url?scp=40349116368&partnerID=8YFLogxK
U2 - 10.1007/s11064-007-9516-5
DO - 10.1007/s11064-007-9516-5
M3 - Article
SN - 0364-3190
VL - 33
SP - 609
EP - 613
JO - Neurochemical Research
JF - Neurochemical Research
IS - 4
ER -