Irisin inhibition of growth hormone secretion in cultured tilapia pituitary cells.
Irisin, the product of fibronectin type III domain-containing protein 5 (FNDC5) gene, is well-documented to be a regulator of energy metabolism. At present, not much is known about its biological function in non-mammalian species. In this study, a full-length tilapia FDNC5 was cloned and its tissue expression pattern has been confirmed. Based on the sequence obtained, we produced and purified recombinant irisin which could induce uncoupling protein 1 (UCP1) gene expression in tilapia hepatocytes. Further, the rabbit polyclonal irisin antiserum was produced and its specificity was confirmed by antiserum preabsorption. In tilapia pituitary cells, irisin inhibited growth hormone (GH) gene expression and secretion and triggered rapid phosphorylation of Akt, Erk1/2, and p38 MAPK. Furthermore, irisin-inhibited GH mRNA expression could be prevented by inhibiting PI3K/Akt, MEK1/2, and p38 MAPK, respectively. Apparently, fish irisin can act directly at the pituitary level to inhibit GH transcript expression via multiple signaling pathways.
Key Laboratory of Bio-resources and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, PR China.
Anji
A
Lian
Key Laboratory of Bio-resources and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, PR China.
Xin
X
Li
Key Laboratory of Bio-resources and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, PR China. Electronic address: jiangqua@gmail.com.
Quan
Q
Jiang
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001681:Biological Assay; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005353:Fibronectins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D013006:Growth Hormone / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007106:Immune Sera / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000235:genetics; D010902:Pituitary Gland / Q000166:cytology*; D011994:Recombinant Proteins / Q000494:pharmacology; D016415:Sequence Alignment; D017210:Tilapia / Q000235:genetics / Q000378:metabolism*; D000071256:Uncoupling Protein 1 / Q000378:metabolism
D018076:DNA, Complementary; C577593:FNDC5 protein, human; D005353:Fibronectins; D007106:Immune Sera; D011994:Recombinant Proteins; D000071256:Uncoupling Protein 1; D013006:Growth Hormone
Growth hormone; Hepatocytes; Irisin; Pituitary cells; Tilapia