Data/hora: 02/06/2024 15:42:05

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 22/11/2002
Data da última atualização: | 22/11/2002
Autoria: | JOHNSON, G. A.; SPENCER, T. E.; BURGHARDT, R. C.; BAZER, F. W.
Título: | Ovine osteopontin: I. Cloning and expression of messenger ribonucleic acid in the uterus during the periimplantation period.
Ano de publicação: | 1999
Fonte/Imprenta: | Biology of Reproduction and Fertility, v. 61, n. 4, p. 884-891, 1999.
Idioma: | Inglês
Conteúdo: | Trophoblast-derived interferon tau (IFNT) acts on the endometrium to increase secretion of several proteins during the pregnancy recognition period in ruminants. One of these is a 70-kDa acidic protein that has not been identified. Our hypothesis was that lhe 70-kDa acidic protein is osteopontin (OPN). OPN is an acidic glycoprotein that fragments upon freezing and thawing or treatment with proteases including thrombin. OPN contains a Gly-Arg-Gly-Asp-Ser (GRGDS) sequence that binds to cell surface integrins to promote cell-cell attachment and cell spreading. Using antisera to recombinant human OPN, both 70-kDa and 45-kDa proteins were identified in uterine flushings from pregnant ewes by Western blotting. A clone containing lhe . entire ovine OPN cDNA coding sequence was isolated by screening a Day 15 pregnant ovine endometrial cDNA library with a partial ovine OPN cDNA. In pregnant ewes, steady-state levels of OPN endometrial mRNA increased (P < 0.01) after Day 17. In both cyclic and pregnant ewes, in situ hybridization analysis showed that OPN mRNA was localized on unidentified immune cells within the stratum compactum of the endometrium. In pregnant ewes, OPN mRNA was also expressed by the glandular epithelium. Results suggest that progesterone and/or IFNT induce expression and secretion of OPN by uterine glands during the periimplantation period and that OPN mar induce adhesion between luminal epithelium and trophectoderm to facilitate superficial implantation.
Palavras-Chave: | Ácido ribonucleico; Endometrio.
Thesagro: | Endocrinologia; Hormônio; Ovino; Prenhez; Reprodução Animal; Útero.
Categoria do assunto: | --
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (15145-1) - ADC - AP - -- -  -  - v.61, n.4 - DIS