UNASSIGNED: Transcription factor Forkhead box protein M1b ( @entity4009 ) plays an important role during mitotic entry and progression. Our previous studies identified @entity9370 ( @entity9370 ) as a major regulator of @entity4009 . During G2/M transition, @entity9370 directly interacts with and phosphorylates @entity4009 , resulting in full activation of transactivation capacity of @entity4009 . Such a vital regulatory mechanism is essential for timely mitotic entry and progression; however, the molecular mechanism by which @entity9370 -mediated phosphorylation enhances @entity4009 's transcriptional activity remains to be determined. We demonstrate that @entity4009 can be SUMOylated in vitro and in vivo, preferentially by @entity16926 . SUMOylation of @entity4009 was found to occur at multiple sites, leading to suppression of @entity4009 's transcriptional activity. Such a post-translational modification of @entity4009 was antagonized by @entity9370 -mediated phosphorylation. By immunofluorescence staining and subcellular fractionation, we demonstrate that SUMO conjugation promotes cytosolic translocation of @entity4009 . Moreover, SUMO modification of @entity4009 facilitates the ubiquitin-mediated proteasomal degradation of @entity4009 . @entity9370 -mediated phosphorylation of @entity4009 abrogates the inhibitory effect on @entity4009 by SUMO modification, thereby promoting its nuclear translocation and preventing its proteolytic degradation in the cytoplasm. Such an antagonistic regulatory mechanism is essential for @entity4009 's mitotic function, ensuring timely mitotic entry and progression. Taken together, our studies have revealed a working mechanism by which @entity9370 positively regulates the activity and level of @entity4009 , which would greatly facilitate therapeutic interventions that focus on targeting the @entity9370 -mediated and/or @entity4009 -mediated signaling network.

XXXX -mediated phosphorylation of Forkhead box protein M1b antagonizes its SUMOylation and thereby facilitates its mitotic function.

@entity4009 :: ('2305', 'Gene') :: ['FoxM1', 'FoxM1b'] @entity16926 :: ('7341', 'Gene') :: ['SUMO-1'] @entity9370 :: ('5347', 'Gene') :: ['PLK1', 'polo-like kinase 1']
@entity9370 :: (5347,Gene) :: ['Polo-like kinase 1']
