Molecular cloning and characterization of pirarucu (Arapaima gigas) follicle-stimulating hormone and luteinizing hormone beta-subunit cDNAs

作者:Sevilhano Thais; de Carvalho Roberto Feitosa; de Jesus Oliveira Nelio Alessandro; Oliveira Joao Ezequiel; Maltarollo Vinicius Goncalves; Trossini Gustavo; Garcez Riviane; Bartolini Paolo*
来源:PLos One, 2017, 12(8): e0183545.
DOI:10.1371/journal.pone.0183545

摘要

The common gonadotrophic hormone alpha-subunit (GTH alpha) has been previously isolated by our research group from A. gigas pituitaries; in the present work the cDNA sequences encoding FSH beta and LH beta subunits have also been isolated from the same species of fish. The FSH beta-subunit consists of 126 amino acids with a putative 18 amino acid signal peptide and a 108 amino acid mature peptide, while the LH beta-subunit consists of 141 amino acids with a putative 24 amino acid amino acid signal peptide and a 117 amino acid mature peptide. The highest identity, based on the amino acid sequences, was found with the order of Anguilliformes (61%) for FSH beta and of Cypriniformes (76%) for LH beta, followed by Siluriformes, 53% for FSH beta and 75% for LH beta. Interestingly, the identity with the corresponding human amino acid sequences was still remarkable: 45.1% for FSH beta and 51.4% for LH beta. Three dimensional models of ag-FSH and ag-LH, generated by using the crystal structures of h-FSH and h-LH as the respective templates and carried out via comparative modeling and molecular dynamics simulations, suggested the presence of the so-called "seat-belt", favored by a disulfide bond formed between the 3rd and 12th cysteine in both beta-subunits. The sequences found will be used for the biotechnological synthesis of A. gigas gonadotrophic hormones (ag-FSH and ag-LH). In a first approach, to ascertain that the cloned transcripts allow the expression of the heterodimeric hormones, ag-FSH has been synthesized in human embryonic kidney 293 (HEK293) cells, preliminarily purified and characterized.

  • 出版日期2017-8-28