Suspension HeLa cells were grown in DMEM, 10% FCS, Pen/Strep and split 1:2 the day before harvesting.
Extracted molecule
polyA RNA
Extraction protocol
mRNAs were isolated by immunoprecipitation from 200ul of precleared HeLa cell extract, using the anti-U2AF65 MC3 mAb (Gama-Carvalho, Krauss et al. 1997) or the Bb7 anti-PTB mAb (ATCC) for 2h at 4C. Immune complexes were precipitated with a slurry with 50% of protein A/protein G agarose beads (Amersham), blocked with 100ug/ul of tRNA and RNAse free BSA (Ambion), by rotating for 1h at 4C and washed with lysis buffer. Complexes bound to the beads were eluted with TES buffer (10mM Tris, 0.5M EDTA, 0.5% SDS, pH 8.0) by heating at 65C for 10 minutes and Trizol extracted. Polyadenilated RNA in the cell extract (input) and in the immunoprecipitation sample was reverse transcribed, end-tagged and PCR amplified using the Super SMART PCR cDNA synthesis kit from Clontech, following manufacturer instructions. 1ug of input or precipitated RNA was used per RT-PCR reaction to produce samples for microarray hybridization. For each set of samples (input and immunoprecipitated) a 100ul test PCR reaction was performed according to manufacturer instructions and analyzed by agarose gel electrophoresis to select ideal conditions for amplification in the linear range. PCR reactions were pooled to obtain enough material for microarray hybridization.
Label
biotin
Label protocol
15ug of PCR amplified cDNA from input and immunoprecipitated samples were fragmented, end labeled with biotin
Hybridization protocol
hybridized to Affymetrix GeneChip Human Genome U133 Plus 2.0 Arrays as described (Brodsky, Meyer et al. 2005), following standard Affymetrix hybridization protocols
Scan protocol
Gama-Carvalho et al, 2006
Description
Total cDNA from HeLa cell extract from Immunoprecipitation experiment 2
Data processing
The data were analyzed with dChip using default analysis settings. The model based expression index was calculated using the PM/MM model
