ORIGINAL PAPER A transgenic mouse model for the in vivo bioluminescence imaging of the expression of the lysophosphatidic acid receptor 3: relevance for inflammation and uterine physiology research Chenqi Zhao . Anne Sardella . Lynn Davis . Patrice E. Poubelle . Sylvain G. Bourgoin . Maria J. Fernandes Received: 25 June 2014 / Accepted: 2 May 2015 Ó Springer International Publishing Switzerland 2015 Abstract Lysophosphatidic acid (LPA) is a lipid- derived signaling molecule that plays key roles in diverse biological processes including inflammation and uterine remodeling. Although the function of LPA and its receptors has been extensively studied using knock-out mice, the temporal-spatial expression of LPA receptors is less well-characterized. To gain further insight into the dynamic regulation of LPA receptor 3 (Lpar3) expression in vivo by biolumines- cence imaging, we generated and characterized mice transgenic for a putative Lpar3 promoter fragment. A non-coding region of the Lpar3 gene immediately upstream of the start site was subcloned adjacent to the luciferase gene. Promoter activity was determined by in vitro luciferase assays, in vivo bioluminescent imaging or by semi-quantitative real-time PCR. The air-pouch model was used to investigate Lpar3 promoter activity in the context of inflammation. The putative Lpar3 promoter fragment behaved similarly to the endogenous promoter in vitro and in vivo. In male mice, elevated levels of Lpar3- induced luciferase activity were observed in the testis. In female mice, the basal level of luciferase activity in the uterus significantly increased during pseudopreg- nancy. Moreover, luciferase activity was upregulated by TNF-a in the air-pouch model. We report the identification of a functional Lpar3 promoter fragment and the generation of a transgenic mouse model to investigate the regulation of Lpar3 promoter activity non-invasively in vivo by bioluminescence imaging. This mouse model is a valuable tool for reproductive biology and inflammation research as well as other biological processes in which this receptor is involved. Keywords Lysophosphatidic acid receptor 3 (Lpar3) promoter Á Luciferase 2 (luc2) Á Transgenic mouse model Á Transgenic reporter bioluminescence noninvasive imaging Á Tumour necrosis factor-a (TNF-a) Á Inflammation Introduction Lysophosphatidic acid (LPA) is a bioactive lipid mediator that is involved in numerous physiological and pathological processes such as cell growth, migration, angiogenesis, metastasis, and autoimmuni- ty. The diverse biological functions of LPA are mediated through six G protein-coupled receptors Electronic supplementary material The online version of this article (doi:10.1007/s11248-015-9882-8) contains supple- mentary material, which is available to authorized users. C. Zhao Á A. Sardella Á L. Davis Á P. E. Poubelle Á S. G. Bourgoin (&) Á M. J. Fernandes (&) Rheumatology and Immunology Research Center, Local T1-49, CHUQ-CHUL Research Center and Faculty of Medicine, Laval University, 2705, Boul. Laurier, Que ´bec, QC G1V 4G2, Canada e-mail: sylvain.bourgoin@crchul.ulaval.ca M. J. Fernandes e-mail: maria.fernandes@crchul.ulaval.ca 123 Transgenic Res DOI 10.1007/s11248-015-9882-8