CONICET | Buscador de Institutos y Recursos Humanos

During the preimplantation phase of pregnancy the endometrial stroma differentiates into decidua, a process that implies numerous morphological changes and is an example of physiological transdifferentiation. Here we show that UIII rat endometrial stromal cells cultured in the presence of calf serum acquired morphological features of decidual cells and expressed decidual markers. To identify genes involved in decidualization we compared gene expression patterns of control and decidualized UIII cells using cDNA microarray. We found 322 annotated genes exhibiting significant differences in expression (>3-fold, fold discovery rate (FDR)>0.005), of which 312 have not been previously related to decidualization. Analysis of overrepresented functions revealed that protein synthesis, gene expression, and chromatin architecture and remodeling are the most relevant modified functions during decidualization. Relevant genes are also found in the functional terms differentiation, cell proliferation, signal transduction, and matrix/structural proteins. Several of these new genes involved in decidualization (Csdc2, Trim27, Eef1a1, Bmp1, Wt1, Aes, Gna12, and Men1) are also regulated in uterine deciduas during normal pregnancy. We compared changes in gene expression in serum stimulated decidualized cells with changes observed in UIII cells treated with the ovarian hormones, progesterone and estradiol, the physiological stimuli for decidualization. The mRNA and protein levels of Csdc2, an RNA binding protein that controls transcription and translation of specific genes and is the most up-regulated gene in serum induced decidualization, is also increased during decidualization induced by the combination of progesterone and estradiol. Thus, the UIII cell culture model will allow future mechanistic studies to define the transcriptional network regulating reprogramming of stromal cells into decidual cells.