The 3 0 RACE assay was carried out on total RNA (20 mg) isolated from untreated cells and treated with 1mM H 2 O 2 . DNA 'adaptor' oligonucleotide (W242) carrying aminolinker at the 3 0 -end was ligated with the 3 0 -end of total RNA using 20U of T4 RNA ligase (NEB). Ligation was performed in the presence of 25% PEG1000 (Sigma) at 378C. RNA was extracted with phenol: chloroform: isoamyl alcohol (v/v 25:24:1), precipitated and used as a template for cDNA synthesis using W243 primer complementary to the anchor sequence and the Enhanced Avian HS RT-PCR Kit (Sigma) according to manufacturer's instructions. cDNA was amplified using primers W241 and W243, the resulting PCR product was gel purified, cloned into pGEM-T Easy vector and sequenced using primer W241.