Bovine tissue gene expression profiling at peak lactation

Tissue from mammary, liver, and three adipose depots (mesenteric, omental, and subcutaneous) was collected at slaughter from a cow at peak lactation to examine gene expression profiles of 7872 sequences using a bovine cDNA microarray. Keywords: comparative tissue gene expression RNA (20 ug) from tissues and a reference standard derived from a mixture of tissues were used to make aminoallyl-labeled cDNA followed by incorporation of Cy3-ester and Cy5-ester (Amersham, Piscataway, NJ). Each experimental sample was co-hybridized with the reference standard, which allowed the treatment of fluorescence ratios as measurements of relative expression across all samples and time points. Probes were hybridized to the array for 2 days at 42 C. All samples were hybridized to duplicate slides for a total of 4 spots per cDNA element. The microarray platform has already been described [Everts et al. (2005) Vet. Immunol. Immunopathol. 105:235-245]. Slides were scanned for both dye channels with a Scanarray 4000 (GSI-Lumonics, Billerica, MA) dual-laser confocal scanner and images were processed using GenePix 4.0 (Axon Instruments, Inc., CA).