Mitotic Kinases Aurora-A, Plk1, and Cdk1 Interact with Elk-1 Transcription Factor through the N-Terminal Domain

Figure 1

Interaction of Elk-1 with mitotic kinases. (a) A schematic diagram of the domain structure and predicted mitotic kinase phosphorylation motifs of ternary complex factor Elk-1; predicted Plk phosphorylation motifs are shown in purple, Cdk motifs in orange, Aur-B motif in green, Aur-A motifs in red, and the known ERK/MAPK phosphorylation sites are shown in blue; ETS: E-twenty-six; DBD: DNA binding domain; B: SRF interaction domain; R: repression domain; D: docking domain; C: activation domain (AD). (b) Immunoprecipitation of endogenous Elk-1 in SH-SY5Y cell lines, followed by Western blot with antibodies specific for Aur-A, Aur-B, Cdk1, Plk1, and Elk-1 (IgG is used as IP control). (c) U87 cells were arrested with nocodazole treatment, released into mitosis at time 0 (indicated as 0), and samples were taken at 30 min (30), 60 min (60), and 90 min (90) after release. Immunoprecipitation was performed using Elk-1 antibody, and both input and IP samples were analyzed by Western blot with antibodies specific for Aurora-A, Aurora-B, Cdk1, Plk1, and Elk-1.

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