Molecular cloning of AP-1 transcription factors in Chinese grass carp and their functional roles in PACAP-stimulated growth hormone gene expression

2003 ◽  
Author(s):  
Yonghua Jiang
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Transcription Factors ◽  
Molecular Cloning ◽  
Grass Carp ◽  
Growth Hormone Gene ◽  
Functional Roles

scholarly journals Paracrine regulation of growth hormone gene expression by gonadotrophin release in grass carp pituitary cells: functional implications, molecular mechanisms and signal transduction

2005 ◽  
Vol 34 (2) ◽  
pp. 415-432 ◽  
Author(s):  
Hong Zhou ◽  
Yonghua Jiang ◽  
Wendy K W Ko ◽  
Wensheng Li ◽  
Anderson O L Wong
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Adenylate Cyclase ◽  
Mrna Expression ◽  
Grass Carp ◽  
Janus Kinase ◽  
Growth Hormone Gene ◽  
Pituitary Cells ◽  
Mrna Levels ◽  
Gh Gene

Growth hormone (GH) is known to stimulate luteinizing hormone (LH) release via paracrine interactions between somatotrophs and gonadotrophs. However, it is unclear if LH can exert a reciprocal effect to modulate somatotroph functions. Here we examined the paracrine effects of LH on GH gene expression using grass carp pituitary cells as a cell model. LH receptors were identified in grass carp somatotrophs and their activation by human chorionic gonadotropin (hCG) increased ‘steady-state’ GH mRNA levels. Removal of endogenous LH by immunoneutralization using LH antiserum inhibited GH release and GH mRNA expression. GH secretagogues, including gonadotrophin releasing hormone (GnRH), pituitary adenylate cyclase-activating polypeptide (PACAP) and apomorphine, were effective in elevating GH mRNA levels but these stimulatory actions were blocked by LH antiserum. In pituitary cells pretreated with actinomycin D, the half-life of GH mRNA was not affected by hCG but was enhanced by LH immunoneutralization. Treatment with LH antiserum also suppressed basal levels of mature GH mRNA and primary transcripts. hCG increased cAMP synthesis in carp pituitary cells and hCG-induced GH mRNA expression was mimicked by forskolin but suppressed by inhibiting adenylate cyclase and protein kinase A. Similarly, the stimulatory actions of hCG and forskolin on GH mRNA expression were blocked by inhibiting Janus kinase 2 (JAK2) and MAP kinase (MAPK), including P42/44MAPK and P38 MAPK. These results suggest that LH is essential for the maintenance of GH release, GH gene expression, and somatotroph responsiveness to GH-releasing factors. The paracrine actions of LH on GH mRNA expression are mediated by a concurrent increase in GH gene transcription and GH mRNA turnover, probably through JAK2/MAPK coupled to the cAMP-dependent pathway.

scholarly journals Development of a quantitative competitive reverse transcriptase polymerase chain reaction for the quantification of growth hormone gene expression in pigs

2003 ◽  
Vol 26 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Maurício Machaim Franco ◽  
Juliana Franco Almeida ◽  
Guilherme Rocha Lino de Souza ◽  
Robson Carlos Antunes ◽  
Luiz Ricardo Goulart
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Polymerase Chain Reaction ◽  
Reverse Transcriptase ◽  
Growth Hormone Gene ◽  
Chain Reaction ◽  
Polymerase Chain

scholarly journals Stimulation of Growth Hormone Gene Expression in the Pituitary and Brain by Panax ginseng C. A. MEYER

1999 ◽  
Vol 46 (Suppl) ◽  
pp. S85-S88 ◽  
Author(s):  
HIDEO YOSHIZATO ◽  
TAKAHIKO FUJIKAWA ◽  
MUNEICHI SHIBATA ◽  
MINORU TANAKA ◽  
KUNIO NAKASHIMA
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Panax Ginseng ◽  
Growth Hormone Gene ◽  
Stimulation Of
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