Structure and biological activity of gonadotropin-releasing hormone isoforms isolated from rat and hamster brains

Rat and hamster brain tissues were used to investigate the possible existence of a follicle stimulating hormone (FSH)-releasing factor with similar characteristics to the lamprey gonadotropin-releasing hormone III (lGnRH-III) form proposed in previous reports. The present studies involved isolation...

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Detalles Bibliográficos
Autores: Montaner, Alejandro Daniel, Mongiat, Lucas Alberto, Lux, Victoria Adela R., Park, M. K., Fischer, W. H., Rivier, J. E., Lescheid, D., Lovejoy, D., Libertun, Carlos, Sherwood, N. M., Somoza, Gustavo Manuel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2001
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/31321
Acceso en línea:http://hdl.handle.net/11336/31321
Access Level:acceso abierto
Palabra clave:Gonadotropins
Processing
Structure Function Relationship
Hydroxyproline Gnrh
https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
Descripción
Sumario:Rat and hamster brain tissues were used to investigate the possible existence of a follicle stimulating hormone (FSH)-releasing factor with similar characteristics to the lamprey gonadotropin-releasing hormone III (lGnRH-III) form proposed in previous reports. The present studies involved isolation and purification of the molecule by high-performance liquid chromatography (HPLC), identification by radioimmunoassay, sequence analysis by automated Edman degradation, mass spectrometry and examination of biological activity. Hypothalamic extracts from both species contained an HPLC fraction that was immunoreactive to GnRH and coeluted with lGnRH-III and 9-hydroxyproline mGnRH ([Hyp(9)]GnRH). Determination of primary structure from purified total brain material demonstrated that the isolated molecule was [Hyp(9)]GnRH. This is the first report showing the presence of the posttranslationally modified form already known as [Hyp(9)]GnRH by primary sequence analysis. The biological activity of distinct GnRH peptides was also tested in vitro for gonadotropin release using rat pituitary primary cell cultures. The results showed that [Hyp(9)]GnRH stimulated both luteinizing hormone and FSH release, as already reported, whereas lGnRH-III had no action on the secretion of either gonadotropin.