Ikaros isoforms in human pituitary tumors: distinct localization, histone acetylation, and activation of the 5' fibroblast growth factor receptor-4 promoter.

ABSTRACT: Targeted expression of a human pituitary tumor derived-fibroblast growth factor receptor-4 (FGFR4) recapitulates pituitary tumorigenesis. We have shown that FGFR4 is a target for Ikaros, a zinc finger-containing transcription factor that localizes to heterochromatin regions and participates in higher order chromatin complexes and control of gene expression. We report here the expression of Ikaros and functional differences between its alternatively spliced variants in human pituitary tumors. Ik1 expression was detected in human pituitary tumors and we also identified a truncated isoform consistent with the non-DNA-binding Ik6 isoform in a subset of adenomas by reverse transcriptase-polymerase chain reaction, sequencing, and Western immunoblotting. Transfection of Ik6 in GH4 pituitary cells

SUBMITTER: Ezzat S 

PROVIDER: S-EPMC1868268 | biostudies-literature | 2003 Sep

REPOSITORIES: biostudies-literature