Selective STAT3-α or -β expression reveals spliceform-specific phosphorylation kinetics, nuclear retention and distinct gene expression outcomes.

ABSTRACT: Phosphorylation of STAT3 (signal transducer and activator of transcription 3) is critical for its nuclear import and transcriptional activity. Although a shorter STAT3β spliceform was initially described as a negative regulator of STAT3α, gene knockout studies have revealed that both forms play critical roles. We have expressed STAT3α and STAT3β at comparable levels to facilitate a direct comparison of their functional effects, and have shown their different cytokine-stimulated kinetics of phosphorylation and nuclear translocation. Notably, the sustained nuclear translocation and phosphorylation of STAT3β following cytokine exposure contrasted with a transient nuclear translocation and phosphorylation of STAT3α. Importantly, co-expression of the spliceforms revealed that STAT3β enhanced an

SUBMITTER: Ng IH 

PROVIDER: S-EPMC3441131 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature