Total RNA was extracted and purified using RiboPure RNA Isolation (Ambion). Total RNA samples were quantitated by UV spectrophotometry. Quality of total RNA was assessed using an Agilent Bioanalyzer.
Label
Cy5
Label protocol
Biotin-labelled cRNA was prepared by linear amplification of the poly(A)+ RNA population within the total RNA sample. Briefly, 2 µg of total RNA was reverse transcribed after priming with a DNA oligonucleotide containing the T7 RNA polymerase promoter 5' to a d(T)24 sequence. After second-strand cDNA synthesis and purification of double-stranded cDNA, in vitro transcription was performed using T7 RNA polymerase in the presence of biotinylated UTP.
Hybridization protocol
10 µg of purified cRNA was fragmented to uniform size and applied to CodeLink Mouse Whole Genome Microarrays in hybridization buffer. Arrays were hybridized at 37°C for 18 hrs. in a temperature-controlled shaking incubator, washed at 46°C for 1 hr, and stained with Cy5-Streptavidin dye conjugate for 30 min.
Scan protocol
Rinsed and dried arrays were scanned with an Axon GenePix 4000B Microarray Scanner at 5 µm resolution.
Description
F293Liver
Data processing
CodeLink software was used to process the scanned images from arrays (gridding and feature intensity extraction), and the data generated for each probe on the array was analyzed with GeneSpring GX software (Agilent Technologies, Santa Clara, CA). Intensity values were normalized to the 75th percentile intensity of each array.