Send to

Choose Destination
J Interferon Cytokine Res. 2001 Jun;21(6):369-78.

Involvement of protein phosphatase 2A in the interleukin-3-stimulated Jak2-Stat5 signaling pathway.

Author information

Department of Physiology and Biophysics, School of Medicine, State University of New York at Stony Brook, Stony Brook, NY 11794-8661, USA.


In this study, we report that the tyrosine kinase, Janus kinase 2 (Jak2), associates with the serine/threonine protein phosphatase 2A (PP2A) in 32Dcl3 myeloid progenitor cells. The association between Jak2 and PP2A transiently increases following interleukin-3 (IL-3) stimulation and activation of Jak2. The catalytic subunit of PP2A is tyrosine phosphorylated by Jak2 in vitro and in vivo, resulting in inhibition of phosphatase activity. PP2A also associates with Stat5 in 32Dcl3 cells in an IL-3-dependent manner. Pretreatment of 32Dcl3 cells with okadaic acid (OA), an inhibitor of PP2A, resulted in increased tyrosine phosphorylation and nuclear translocation of Stat5. Our results suggest that PP2A plays a negative regulatory role in regulating the IL-3 signaling pathway via formation of complexes with Jak2 and Stat5.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center