PARENT SESSION
MECHANISMS OF HORMONE ACTION

Tuesday, August 3, 2004
10:30 AM–12:30 PM
Buchanan Courtyard

(354) TRANSCRIPTIONAL PROFILING OF CELLULAR RESPONSES TO OVINE INTERFERON TAU AND HUMAN INTERFERON ALPHA.

Spencer, Thomas¹, Fleming, Jo-Ann¹, Gray, Allison¹, Bazer, Fuller¹, ¹ Texas A&M University, College Station, TX

ABSTRACT- Interferon tau (IFN), a Type I IFN produced by conceptus trophectoderm, increases many Type I IFN-stimulated genes (ISGs) in the ovine uterine endometrial stroma and glandular epithelium (GE) using Stat1-dependent pathways. Most ISGs are not induced or increased by IFN in the Stat1-negative endometrial luminal epithelium (LE). Objectives were to: (1) identify genes regulated by IFN in a Stat1-dependent and -independent manner using DNA microarray and human 2fTGH and U3A (Stat1 null 2fTGH) cells for the endometrial stroma/GE and LE, respectively; and (2) compare effects of ovine IFN and human IFN on gene regulation using 2fTGH cells. The mRNAs from human 2fTGH and U3A cells, treated for 24 h with nothing or recombinant ovine IFN, and from 2fTGH cells treated with recombinant human IFN (Roferon) were profiled using Amersham CodeLink UniSet Human 10K I and 10K 2 Bioarrays. Data were analyzed using GeneSpring 6.1 to determined changes in gene expression that were greater than 2-fold (p<0.05). In 2fTGH cells, IFN and IFN increased the expression of 130 and 81 genes, respectively, including known ISGs such as ISG15, OAS, Mx and Stat1, and decreased expression of 78 and 32 genes, respectively. Although the fold difference between the two Type I IFNs differed in most cases, no uniquely responsive genes were found for either Type I IFN. Genes increased by IFN and IFN in 2fTGH cells included RIG-I RNA helicase and bHLH factor Hes4. Genes decreased by IFN and IFN in 2fTGH cells included L-MYC and HBF-2, a forkhead transcription factor. In U3A cells, IFN increased expression of 49 genes including a phospholipase C, beta 4 and transforming growth factor receptor 1, but decreased the expression of 137 genes including matrix metalloproteinase 23 (MMP-23) and homeobox D3. None of the genes regulated by IFN in 2fTGH cells were similarly regulated by IFN in U3A cells. Expression of 1572 genes was different in untreated 2fTGH versus U3A cells. Therefore, Stat1 is a global regulator of gene transcription and programs the innate ability of cells to respond to Type I IFNs. Elucidation of the IFN signaling pathways in 2fTGH and U3A cells will advance our understanding of gene regulation in the endometrium during pregnancy recognition and implantation as well as the general pathways utilized by other Type I IFNs. Supported by NIH HD32534.

KEY WORDS: endometrium, gene profiling, interferon, cell lines