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Published on: April 30, 2013
Sequence analysis, endocrine regulation, and signal transduction of GnRH receptors in teleost fish
Berta Levavi-Sivan1, Ayelet Avitan
1Department of Animal Sciences, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel. sivan@agri.huji.ac.il
Abstract:
Three gonadotropin-releasing hormones (GnRHs) and three cognate receptors have been identified in vertebrates, with distinct distributions and functions. According to their sequences, the receptors can be grouped into distinct classes: types I, II, and III. One branch contains all type-I GnRH receptors (GnRH-R-I) from mammals and fish; another branch clusters mainly amphibian and human type-II GnRH receptors; and a third branch includes evolved fish, mainly perciform species, type-III GnRH receptors. Taken tilapia GnRH receptors as a model, the present study summarizes the information regarding the amino-acid residues assumed to be involved in the receptors' structure, binding, activation, and intracellular signal transduction, including arrangement of the disulfide bonds, glycosylation sites, coupling to G proteins, and protein kinase A or protein kinase C phosphorylation sites.
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