Regulation of Ovarian Steroidogenesis in Vitro by Gonadotropin in Common Carp Cyprinus Carpio: Interaction Between Calcium- and Adenylate Cyclase-Dependent Pathways and Involvement of ERK Signaling Cascade
EPrints@IICB
View Archive InfoField | Value | |
Title |
Regulation of Ovarian Steroidogenesis in Vitro by Gonadotropin in Common Carp Cyprinus Carpio: Interaction Between Calcium- and Adenylate Cyclase-Dependent Pathways and Involvement of ERK Signaling Cascade |
|
Creator |
Paul, Sudipta
Kundu, Sourav Pramanick, Kousik Bandyopadhyay, Arun Mukherjee, Dilip |
|
Subject |
Cell Biology & Physiology
|
|
Description |
Multiple signal transduction pathways mediating gonadotropin-induced testosterone and 17b-estradiol (E2) production were identified in carp ovarian theca and granulosa cells in short-term co-incubation. Inhibitors of voltage-sensitive calcium channels (VSCCs) and calmodulin attenuated human chorionic gonadotropin (HCG)-induced steroid production, whereas modulators of adenylate cyclase and protein kinase A (PKA) increased their production, indicating that both calcium- and PKA-dependent pathways are involved in the regulation of gonadotropin-induced steroidogenesis in carp ovary. Interactions between these two pathways are evident from the positive effect of elevated intracellular calcium on HCG-induced steroid production and the reduction of forskolin (FK)- and dibutyryl cAMP (dbcAMP)-induced steroidogenesis by inhibitors of VSCCs and calmodulin. In this study, we found the involvement of a third signaling pathway, a mitogen-activated protein kinase (MAP kinase), in the regulation of gonadal steroidogenesis in this fish. An antagonist of mitogen-activated protein kinase kinases 1/2 (MEK1/2; also known as MAP2K1/MAP2K2) markedly attenuated HCG-induced steroid production. Cells treated with HCG stimulated MEK1/2-dependent phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERKs1/2) in a concentration and time-dependent manner. Moreover, ERK1/2 activation in cells was mimicked by FK and dbcAMP suggesting that ERK1/2 transduce signal downstream of PKA in HCG-induced ovarian steroidogenesis. Evidence for presence of cross talk between calcium-dependent pathways and this MAP kinase cascade has been shown by demonstrating the inhibitory effects of verapamil and calmodulin on ERK1/2 activation after HCG stimulation. Our results suggest that activation of ERK1/2 by HCG as well as other agents may be a key mechanism for the modulation of gonadotropin-induced steroidogenesis in carp ovary. Journal of Molecular Endocrinology |
|
Date |
2010
|
|
Type |
Article
PeerReviewed |
|
Format |
application/pdf
|
|
Identifier |
http://www.eprints.iicb.res.in/1027/1/18_JME_2010.pdf
Paul, Sudipta and Kundu, Sourav and Pramanick, Kousik and Bandyopadhyay, Arun and Mukherjee, Dilip (2010) Regulation of Ovarian Steroidogenesis in Vitro by Gonadotropin in Common Carp Cyprinus Carpio: Interaction Between Calcium- and Adenylate Cyclase-Dependent Pathways and Involvement of ERK Signaling Cascade. Journal of Molecular Endocrinology, 45 (4). pp. 207-218. |
|
Relation |
http://dx.doi.org/10.1677/JME-10-0061
http://www.eprints.iicb.res.in/1027/ |
|