Characterization and expression of the mouse tat interactive protein 60 kD (TIP60) gene

Abstract

Tat interactive protein-60 (TIP60) is a novel histone acetyltransferase-containing protein that has been implicated in the regulation of transcription, DNA repair and apoptosis. In this report we describe the structure and expression of the mouse TIP60 gene, as well the localization of TIP60 protein at the cellular level. The gene contains 14 exons within a DNA sequence interval of 6611 bp. The assembled exons comprise a 1,539 bp DNA complementary to RNA (cDNA) having 91.7 and 78.7% homology with respective human and chick TIP60 cDNAs. Translation predicts a ∼59 kD protein having 99.6 and 91.6% sequence homology with respective human and chick proteins. Alignment with mouse expressed sequence tag database entries indicates, similar to human and chick TIP60, the existence of an alternative splice created by removal of exon 5 that results in a 1383 bp cDNA with a predicted translation product of ∼53 kD. Northern hybridization analysis reveals a peak of TIP60 expression during mouse embryogenesis at E11; in adult tissues TIP60 is expressed in the following order of intensity: testis>heart>brain>kidney>liver>lung, with little to no expression in spleen and skeletal muscle. Cellular localization using green fluorescent protein-TIP fusion constructs and immunohistochemistry reveal that TIP53 and TIP60 are nuclear proteins.