Project description:The Del-Mar 14K chip was used to interrogate differential expression of transcripts in the white isthmus (WI) compared with the adjacent magnum (Mg) and uterine (Ut) segments of the hen oviduct. Differential expression of genes common to both comparisons (WI/Mg and WI/Ut) was detected for 204 annotated proteins. Of these, 58 genes were overexpressed in both WI/Mg and WI/Ut, and are therefore considered to be the most interesting candidates for WI - specific functions. Additionally, general analysis revealed 135 clones hybridizing to overexpressed transcripts (WI/Mg + WI/Ut), and corresponding to 102 NCBI annotatated non-redundant Gallus gallus gene ID~s. This combined analysis revealed that structural proteins highly over-expressed in white isthmus were collagen X (COL10A1), Fibrillin (FBN1) and Cysteine Rich Eggshell Membrane Protein (CREMP). In addition, genes encoding collagen-processing enzymes were over-expressed, as were proteins known to regulate disulfide cross-linking, suggesting that coordinated upregulation of gene networks in the white isthmus is associated with eggshell membrane fibre formation. IPA interactome analysis reinforces the key role of the estrogen receptor and SMAD3 in mediating gene regulation during eggshell membrane synthesis. These results will assist with development of selection strategies to improve eggshell quality and food safety of the table egg. Keywords: Laying hen, eggshell, oviduct, Isthmus expression, cDNA microarray, indirect cDNA labelling, Alexa Fluor dyes Keywords: Expression profiling by array
