STAT3 nuclear import is independent of tyrosine phosphorylation and mediated by importin-alpha3.

ABSTRACT: Signal transducer and activator of transcription (STAT)3 is a member of a family of DNA-binding factors that function to induce expression of responsive genes. STAT3 can act as an oncogene, and its function has been shown to be critical for cellular transformation by a number of oncogenic tyrosine kinases. The role of STAT3 as a DNA-binding transcription factor naturally depends on its ability to gain entrance to the nucleus. In this study, we provide evidence that STAT3 is distinct from previously characterized STAT molecules in that it dynamically shuttles between cytoplasmic and nuclear compartments and maintains prominent nuclear presence. Although tyrosine phosphorylation is required for STAT3 to bind to specific DNA target sites, nuclear import takes place constitutively and independ

SUBMITTER: Liu L 

PROVIDER: S-EPMC1149424 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature