title: LEFTY2 expression and localization in rat oviduct during early pregnancy.
abstract: In mammals, fertilization and preimplantation embryo development occurs in the oviduct. Cross-talk between the developing embryos and the maternal reproductive tract has been described in such a way as to show that the embryos modulate the physiology and gene expression of the oviduct. Different studies have indicated that transforming growth factor beta (TGF-β) can modulate the oviductal microenvironment and act as an autocrine/paracrine factor on embryo development. LEFTY2, a novel member of the TGF-β superfamily is involved in the negative regulation of other cytokines in this family such as nodal, activin, BMPs, TGF-β1 and Vg1. In previous studies, we have reported that LEFTY2 is differentially expressed in the rat oviduct during pregnancy. In this study, we describe the temporal pattern of LEFTY2 in pregnant and non-pregnant rat oviduct by western blotting, which showed higher levels of LEFTY2 on day 4 of pregnancy, a time at which the embryos are ending their journey along the oviduct. The cellular location of LEFTY2 was assessed by immunohistochemistry, which showed immunolabelling in the cytoplasm and at the apical surface of the oviductal epithelial cells. The oviductal fluid also presented a 26 kDa band, which corresponds to the biologically active form of this protein, at the preimplantation period of pregnancy, indicating LEFTY2 secretion to the lumen. As LEFTY2 is expressed at a high level just before the embryos pass to the uterus, its biological effect might be relevant and significant for the preimplantation stage of embryo development in the oviduct. The fact that embryos do not express LEFTY2 at this stage of development supports this hypothesis.
authors.affiliation: Instituto Superior de Investigaciones Biológicas (CONICET-UNT), Chacabuco 461, 4000, Tucumán, Argentina.
authors.forename: Martin Eduardo
authors.initials: ME
authors.lastname: Argañaraz
authors.forename: Silvana Andrea
authors.initials: SA
authors.lastname: Apichela
authors.forename: Dora Cristina
authors.initials: DC
authors.lastname: Miceli
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003593:Cytoplasm / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D030762:Estrous Cycle / Q000378:metabolism; D005187:Fallopian Tubes / Q000166:cytology / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D055458:Left-Right Determination Factors / Q000235:genetics / Q000378:metabolism*; D008297:Male; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D055458:Left-Right Determination Factors