INVESTIGADORES
MORI SEQUEIROS GARCIA Maria De Las Mercedes
congresos y reuniones científicas
Título:
SPATIO-TEMPORAL REGULATION OF ERK ACTIVITY BY hCG IN LEYDIG CELLS: PARTICIPATION OF DIFFERENT MAP KINASE PHOSPHATASES (MKPs)
Autor/es:
MORI SEQUEIROS GARCÍA MM; GOMEZ NV; BRION L; GOROSTIZAGA AB; ACQUIER AB; DUARTE A; MENDEZ CF; PODESTA EJ; PAZ C
Lugar:
Texas
Reunión:
Congreso; CONFERENCE ON THE ADRENAL CORTEX 2012; 2012
Resumen:
Several MKPs regulate ERK activity. We have demonstrated that nuclear
MKP-1 is rapidly induced by hCG and cAMP through transcriptional and posttranslational
mechanisms in MA-10 Leydig cells. MKP-1 down-regulation by small interfering RNA
increases the hormonal effects on ERK1/2 activity, StAR gene expression and
steroidogenesis. MKP-3 is a cytosolic enzyme induced by proliferative signals.
Here we show that hCG also regulates MKP-3, as this hormone and 8Br-cAMP transiently
increased MKP-3 mRNA levels (2-fold at 3 h stimulation). These two stimuli also
increased flag-MKP-3 levels as assessed by Western blot using an anti-Flag
antibody. Since the chimaera is under the control of a constitutive promoter,
this result suggests that a hormone-induced post translational modification increases
MKP-3 half-life. Moreover, 8Br-cAMP stimulation resulted in flag-MKP-3 accumulation
in the cytosol and reduced ERK1/2 phosphorylation. Thus, induction of MKP-3 and MKP-1 by LH/hCG could
exert a strict spatio-temporal control on MAP kinases to regulate different
events such as proliferation and steroidogenesis.