Expression of uterine sensitization-associated gene-1 (USAG-1) in the mouse uterus during the peri-implantation period.
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 tissue-specific 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.
Maeda
Kanami
K
Research Unit for Functional Genomics, National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
Lee
Dong-Soo
DS
Yanagimoto Ueta
Yoshiko
Y
Suzuki
Hiroshi
H
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001757:Blastomeres / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000235:genetics*; D010064:Embryo Implantation / Q000502:physiology*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008813:Mice, Inbred ICR; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D011555:Pseudopregnancy / Q000503:physiopathology; D012333:RNA, Messenger / Q000378:metabolism; D014599:Uterus / Q000502:physiology*
D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; D012333:RNA, Messenger; C483887:Sostdc1 protein, mouse