Abstract

Recognized for its traditional roles, estrogen is ever-present in all vertebrates, regulates reproduction by binding and activating estrogen receptors (ERs), and also controls several functions of vertebrates, including reproductive immune, and central nervous systems. In order to access any other possible functions of the estrogen receptors in the development of the juvenile Hybrid grouper (Epinephelus fuscoguttatus â™€× Epinephelu polyphekadion ♂), full-length of ERs cDNA sequences were isolated and analyses were found to be 2391 bp for hgERα, 2626 bp for gERb1 and 2339 bp for hgERb2, respectively. The results of amino acid and phylogenetic analysis revealed that each hgER was grouped in consistent taxonomic groups of perciformes and demonstrated great evolutional conservation in functional domains. Real-time PCR examination discovered that the receptors expressed in all tissues examined, though, at a different level, the ERα mRNA level expressed higher than ERβ1, and ERβ2 in tissues examined. The ERα mRNA level of expression was found to be highest in the tissue of the heart, followed by muscle, and liver. The ERβ1 mRNA level was greatest in heart tissue, trailed by liver and muscle and ERβ2 was highest in the heart trailed by stomach and liver. The minimal expression was recorded in the kidney, the gill, and the brain for ERα, ERβ1, and ERβ2 respectively. These results put forward that steroid hormone estrogen receptors might be playing a significant part in the controlling of social behavior complexity, plasticity behavior, and the assessment of a gratifying inducement in Hybrid grouper.

Key words: Estrogen receptors, Real-time POR, tissue expression, hybrid grouper.