Obtention and characterization of cDNA corresponding to the beta subunit of pirarucu thyroid stimulating hormone (TSH) (Arapaima gigas)

• Grant number: 18/10697-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2019
• End date: December 31, 2019
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Carlos Roberto Jorge Soares
• Grantee: Renan Passos Freire
• Host Institution: Instituto de Pesquisas Energéticas e Nucleares (IPEN). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

The Arapaima gigas (Pirarucu) is a fish of the family of Osteoglossiformes, naturally Brazilian that is on exploitation according to IBAMA due to its predatory fishing and illegal trade. Your difficulty in captive breeding makes it possible to study the possible administration of recombinant gonadotropic hormones (FSH, LH and TSH) in order to stimulate their reproduction under breeding conditions. Several studies with fish have shown that thyroid hormones act both in the stimulation of the release of the gonadotrophic hormones (LH and FSH) and the sexual development of the female and male by different routes. Thyroid stimulating hormone (or thyrotropin, TSH) is a heterodimeric glycoprotein that regulates the synthesis of thyroid hormones, triiodothyronine (T3) and thyroxine (T4), increasing or decreasing its expression. These hormones participate in various organs of our body, especially in iodine uptake, cerebral and sexual development of vertebrates. TSH also has a common alpha-subunit with luteinizing (LH) and follicle-stimulating hormone (FSH), whereas the beta-protein chain confers the specificity of each hormone. Pirarucu FSH (ag-FSH) has recently been cloned, characterized and expressed in mammalian cells in our Laboratory of Pituitary Hormones of the Institute of Energy and Nuclear Research (IPEN) located at the University of São Paulo (USP). The group has extensive experience in the expression of recombinant human proteins, such as prolactin, thyrotropin and growth hormone. The objective of this work is to obtain and characterize the gene corresponding to the beta subunit of Arapaima gigas TSH. The results of this work will be the basis for future phylogenetic and three-dimensional modeling studies of Arapaima gigas, as well as ag-TSH expression in mammalian cells.