Expression of Uterine Sensitization-Associated Gene-1 (USAG-1) in the Mouse Uterus During the Peri-Implantation Period

Abstract

Abstract. Rat uterine sensitization-associated gene-1 (USAG-1) mRNA is expressed in the uterus during the peri-implantation period, and its mRNA expression in uterine epithelial cells is highest on day 5 of pregnancy. On the other hand, since changes in USAG-1 mRNA expression in the mouse uterus are not seen during the estrous cycle, USAG-1 expression might be specifically regulated by embryonic factors rather than by the maternal environment. However, the expression pattern and function of USAG-1 in the mouse uterus have not been determined. Thus, we examined the tissuespecific USAG-1 mRNA expression in the uteri of ICR mice during peri-implantation using real-time quantitative PCR. Uterine tissues, such as the myometrium, luminal epithelium, and stroma, were collected by laser capture microdissection at 3.5-6.5 dpc. USAG-1 mRNA was expressed in the uteri of pregnant mice from 3.5 dpc to 6.5 dpc, and the highest level of expression was seen at 4.5 dpc (P<0.01). Significantly high USAG-1 mRNA expression was detected in the luminal epithelium at 4.5 dpc (P<0.05). The stroma and myometrium exhibited unchanged expression levels of USAG-1 mRNA at 3.5-5.5 dpc. USAG-1 mRNA was undetectable in blastocysts and implanting embryos. Expression of USAG-1 mRNA appears to be associated with blastocyst implantation to the luminal epithelium, suggesting that physiological or biochemical contact of the blastocyst to the uterus is required for USAG-1 expression. Key words: Implantation, Mouse, mRNA, Uterine sensitization-associated gene-1 (USAG-1), Uterus (J. Reprod. Dev. 53: [931][932][933][934][935][936] 2007) or successful establishment of pregnancy, blastocyst development must proceed beyond the attachment stage and result in endometrial decidualization and subsequent placental formation. Estrogen and progesterone regulate the events that lead to the receptivity and sensitization of the endometrium for the decidual cell reaction [1]. In rodents and humans, implantation is i n i t i a t e d w i t h a n a p p o s i t i o n b e t w e e n t h e trophoblast and apical surface of the luminal epithelium. This is followed rapidly by adhesion of the conceptus to the luminal surface and then penetration through the luminal epithelium to the underlying stroma, which initiates the endometrial d e c i d u a l i z a t i o n r e a c t i o n [ 2 , 3 ] . U t e r i n e sensitization-associated gene-1 (USAG-1), a gene of unknown function during conceptus development, is upregulated in the sensitized endometrium of the rat uterus during the peri-implantation period [4].

Sost and its paralog Sostdc1 coordinate digit number in a Gli3-dependent manner

“…4L), the urogenital system, teeth, connective tissue and periosteum. Previously published reports have described several phenotypes associated with these expression domains including roles in tooth development (Kassai et al, 2005), hair follicle development (Narhi et al, 2008, 2012), urogenital system development (Maeda et al, 2007), kidney development and toxicity (Tanaka et al, 2008), and more recently pancreas metabolism (Henley et al, 2012). While Sostdc1 expression has not been described in the context of muscle tissue, the robust intermittent expression pattern is consistent with a described role for WNT signaling in the identity of muscle fiber types (Tee et al, 2009; von Maltzahn et al., 2012).…”

Use of laser microdissection in the analysis of renal-infiltrating T cells in MRL/lpr mice

“…There are some Maeda et al [41] prepared 12-16 lm-thick sections and Khodosevich et al [42] dissected 3,000-5,000 cells by LMD for a qRT-PCR experiment. However, in the present study, we were afraid that the amount of RNA necessary for qRT-PCR would not be obtained.…”

Avaliação histologica e da expressão genica de BMP e Wnt no endometrio durante a implantação embrionaria em bovinos

“…Esclerotin, codificado pelo gene Sost, é outro antagonista de BMP abundantemente expresso em osso e cartilagem o qual se liga a BMP6 e BMP7 com alta afinidade e a BMP2 e BMP4 com baixa afinidade (Kusu et al, 2003), cuja expressão já foi identificada no rim humano e no coração de camundongos neonatos (Van Bezooijen et al, 2005). Esse antagonista é da mesma família do USAG-1 (uterine sensitization-associated gene-1) que é predominantemente expresso no útero de ratos pseudo-grávidos (Simmons & Kennedy, 2002), camundongos no período peri-implantacional (Maeda et al, 2007) e no rim em desenvolvimento (Yanagita et al, 2004).…”

“…Por conseguinte, este antagonista não deve ter uma atuação preponderante na regulação da ação da BMP na mucosa uterina da CAR ou IC. Porém, considerando que a proteína USAG, um membro da família DAN de antagonistas na qual SOSTDC1 se inclui, foi identificada no epitélio luminal no 4,5dg em camundongos(Maeda et al, 2007) e no epitélio glandular de ratos pseudo-grávidos(Simmons & Kennedy, 2002) não se pode excluir a possibilidade de que outras proteínas dessa família atuem no endométrio de bovinos, regulando a ação das BMPs nas modificações que acontecem na CAR.O fato do antagonista Noggin ser expresso tanto na região IC quanto CAR do útero NG e gestante de P1 a P4, revela a sua participação na regulação das BMPs, o que vem ao encontro dos relatos de Paria e colaboradores (2001) que verificaram a expressão deste antagonista no estroma subepitelial durante a implantação embrionária de camundongos. Contudo, a sua maior expressão na IC em relação à CAR, sugere a sua menor ou ausência de influência nas alterações da mucosa caruncular.…”