Promotes megakaryocyte differentiation by enhancing ERK and JNK signaling as well as up-regulating RUNX1 and FLI1 expression (By similarity). Represses NF-kappa-B transcriptional activity by inhibiting phosphorylation of RELA at 'Ser- 536' (By similarity). May be involved in early neuronal development (By similarity). Phosphorylation at Tyr-34 is essential for its ability to promote megakaryocyte differentiation. Belongs to the MTURN family.