Journal
MOLECULAR AND CELLULAR BIOCHEMISTRY
Volume 290, Issue 1-2, Pages 177-184Publisher
SPRINGER
DOI: 10.1007/s11010-006-9185-8
Keywords
CREB; real-time monitoring; granulosa cell; ovarian autocrine; paracrine factors
Categories
Ask authors/readers for more resources
The present study was performed to establish a real-time monitoring of the cAMP response element binding protein (CREB) signalling using granulosa cells, and to assess the modulation of CREB activity by potential ovarian autocrine/paracrine and oocyte-derived factors. Granulosa cells were isolated from porcine follicles and cultured for 2 days, and then transfected with CRE-containing pGL3. The cells were directly stimulated or cultured with FSH, LH, forskolin, or a permeable cAMP analog, and/or IGF-I, EGF, bFGF, TGF-beta 2 or TNF-alpha, or cumulus-oocyte complex (COCs) for the real-time monitoring of CREB signaling. The activation pattern of CREB signaling consisted of three distinct phases, i.e., burst, attenuation and refractory. In contrast to FSH, LH, and forskolin, a cAMP analog induced the prolonged activation, although three distinct phases were observed at its high concentration. Of all the autocrine/paracrine factors, only IGF-I slightly induced CREB activity. On the other hand, TGF-beta 2 and TNF-alpha significantly repressed FSH-stimulated transcriptional activation of CREB by 30% (P < 0.05) and 45% (P < 0.05), respectively. Additionally, coculture with COCs caused a significant suppression of transcriptional activation of CREB signaling stimulated by FSH. These results indicate that ovarian autocrine/paracrine factors such as IGF-I, TGF-beta 2, TNF-alpha and oocyte-derived factors modulate the CREB signaling. The present study provides a new approach for direct signaling study on transcription factors under the influences of potential factors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available