|Roberts, Andrew - Andy|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 3/10/2006
Publication Date: 7/1/2006
Citation: Roberts, A.J., Mclean, D.J. 2006. Microarray analysis of gene expression in anterior pituitary glands from anestrous and cycling postpartum beef cows. Journal of Animal Science Supplement 84(Suppl. 2):158. Interpretive Summary:
Technical Abstract: Oligionucleotide microarrays (GeneChip Bovine Genome Arrays, Affymetrix Inc., Santa Clara, CA) were used to evaluate gene expression profiles in anterior pituitary glands collected from four anestrous and four cycling postpartum beef cows. Anestrous cows were slaughtered 40 to 61d after calving at ~2 yr of age. Cycling cows were slaughtered 7 to 13 d after estrus, at 54 to 77 d after calving. Anterior pituitary tissue was collected and snap-frozen in liquid nitrogen within 22 to 37 min after exsanguination. Total RNA was isolated from each sample and was reverse transcribed into double stranded cDNA and subsequently transcribed in the presence of biotinylated UTP to generate target for hybridization on the Bovine Genome GeneChip . Each sample was hybridized to an individual Genechip containing 24,027 total probe sets including 23,080 bovine transcripts representing 19,000 unigene clusters as of March 2004. Levels of expression were compared across arrays using GeneChip Operating Software (GCOS; Affymetrix). Nine transcripts were expressed at greater levels in pituitaries from cycling cows than anestrous cows, including: IGFBP-3, gastrin-releasing peptide (GRP), claudin 1 (CLDN1), transcripts exhibiting >91% homology to the human genes 2-hydroxyphytanol-CoA lyase (2-HPCL) and Kelch-related protein 1 (KRP1), and 4 uncharacterized transcripts (Unigene ID Bt.2501, Bt.10261, Bt.12034 and Bt.14570). Transcripts expressed at lower levels in cycling than anestrous cows included: signal transducer and activator of transcription 3 (Stat3), versican (CSPG2), translation initiation factor eIF-4E (eIF-4E), microsomal glutathione- S-transferase (MGST1), protein S alpha (PROS1), and two uncharacterized transcripts (Unigene ID Bt.33897 and Bt.25587). Although further study is required to confirm the role of these genes in the transition from anestrous to cycling status, results demonstrate potential of this methodology for identifying novel mechanisms regulating reproductive function.