These results suggest a role for Stat5 in regulation of Epo-mediated cell growth and implicate altered kinetics of Epo-induced Jak2 and Stat5 activation in the pathogenesis of familial erythrocytosis associated with this naturally occurring EpoR gene mutation.
We show that cells engineered to concomitantly express the wild-type (WT) EPOR and mutant EPORs associated with FE (FE EPORs) are hypersensitive to EPO-stimulated proliferation and activation of Jak2 and Stat5.