| TIP49b , a regulator of activating transcription factor 2 response to stress and DNA damage . ^^^ A yeast two hybrid screen identified TBP interacting protein 49b ( TIP49b ) , a component of the INO 80 chromatin remodeling complex , as a novel ATF 2 interacting protein . ^^^ TIP49b ' s association with ATF 2 is phosphorylation dependent and requires amino acids 150 to 248 of ATF 2 ( ATF 2 ( 150 248 ) ) , which are implicated in intramolecular inhibition of ATF 2 transcriptional activities . ^^^ Forced expression of TIP49b efficiently attenuated ATF 2 transcriptional activities under normal growth conditions as well as after UV treatment , ionizing irradiation , or activation of p 38 kinase , all of which induced ATF 2 phosphorylation and increased TIP49b ATF 2 association . ^^^ Constitutive expression of ATF 2 ( 150 248 ) peptide outcompeted TIP49b interaction with ATF 2 and alleviated the suppression of ATF 2 transcriptional activities . ^^^ |