Western blotting 1:1000

The p53 family member, p73, exists in multiple isoforms/splice variants and can induce apoptosis and cell cycle arrest in response to DNA damage via its activity as a transcription regulator (1-3). Upon DNA damage, p73 is phosphorylated at Tyr99 by c-Abl, causing translocation to the nuclear matrix (4). DNA damage-induced acetylation of p73 at Lys321 by the acetyltransferase p300 has also been reported to enhance transcription of genes including that of p53AIP1 (5). Another report, however, indicates that p300 does not acetylate full length p73 in vivo (6). While the sequences surrounding p73 Tyr99 and p63 Tyr149 are very similar, only p73 co-localizes with c-Abl following gamma irradiation, suggesting that p63 is not a c-Abl substrate (7).Phospho-p73 (Tyr99) Antibody detects endogenous levels of p73 only when phosphorylated at tyrosine 99. This antibody cross-reacts with p63 when phosphorylated at tyrosine 149.