title: DNA microarray analysis of region-specific gene expression in the mouse epididymis.
abstract: Microarray analysis was carried out to identify genes with enriched expression in the initial segment region of the mouse epididymis. A set of approximately 15 000 clones developed at the National Institutes for Aging and consisting of expressed sequence tags (ESTs) derived from pre- and peri-implantation embryos, Embryonic Day 12.5 female gonad/mesonephros, and newborn ovary were hybridized with probes generated against the initial segment (epididymal region 1) and the remainder of the epididymis (epididymal regions 2-5). The median values for the normalized ratios of region 1 to regions 2-5 from three independent experiments were averaged for each gene/EST using Genespring 5.0 software. The majority of clones showed a ratio of 1.0, suggesting they were expressed at similar levels in all epididymal regions. In addition, 123 clones exhibited 2-fold or higher expression in the initial segment, including Cres3, prostein, lipocalin 2, ALEX3, synaptotagmin-like 4, erm, and milk fat globule factor, whereas 216 clones, including elafin-like 1, lactotransferrin, Sin3B, zinc-finger protein 91, and membrane-type frizzled-related protein, showed 2-fold or higher expression in epididymal regions 2-5. Northern blot analyses of 12 clones predicted by microarray analysis to be either enriched in the initial segment (n = 8), enriched in epididymal regions 2-5 (n = 2), or similar in all regions (n = 2) were carried out. All clones exhibited the expected region-specific expression, thus confirming the microarray results. The studies presented here show a global survey of region-specific gene expression in the epididymis, identifying 15287 sequences, the majority of which have not previously been shown to be expressed in this organ.
authors.affiliation: Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA.
authors.forename: Nelson
authors.initials: N
authors.lastname: Hsia
authors.forename: Gail A
authors.initials: GA
authors.lastname: Cornwall
mesh_terms: D000818:Animals; D004822:Epididymis / Q000502:physiology*; D015870:Gene Expression; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D020411:Oligonucleotide Array Sequence Analysis / Q000592:standards; D015203:Reproducibility of Results