Tyrosine phosphorylation regulates the partitioning of STAT1 between different dimer conformations.

ABSTRACT: The activation/inactivation cycle of STAT transcription factors entails their transition between different dimer conformations. Unphosphorylated STATs can dimerize in an antiparallel conformation via extended interfaces of the globular N-domains, whereas STAT activation triggers a parallel dimer conformation with mutual phosphortyrosine:SH2 domain interactions, resulting in DNA-binding and nuclear retention. However, despite the crucial role of STAT tyrosine phosphorylation in cytokine signaling, it has not been determined how this modification affects the stability and the conformational flexibility of STAT dimers. Here, we use analytical ultracentrifugation and electrophoretic mobility shift assay (EMSA) to study the association of STAT1 in solution before and after tyrosine phosphorylat

SUBMITTER: Wenta N 

PROVIDER: S-EPMC2453697 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature