Cell cycle-dependent phosphorylation of MAN1.
The LEM (LAP2beta, Emerin, and MAN1) proteins are essential for nuclear membrane targeting to chromatin via an association with barrier-to-autointegration factor (BAF). Herein, we focused on the mitotic phosphorylation of MAN1 and its biological role. MAN1 was phosphorylated in a cell cycle-dependent manner in the Xenopus egg cell-free system, and the mitotic phosphorylation at the N-terminal region of MAN1 suppressed the binding of MAN1 to BAF. Titansphere column chromatography followed by MS/MS sequencing identified at least three M-phase-specific phosphorylation sites, Thr-209, Ser-351, and Ser-402, and one cell cycle-independent phosphorylation site, Ser-463. An in vitro BAF binding assay involving mutants S402A and S402E suggested that the phosphorylation of Ser-402 was important for regulation of the binding of MAN1 to BAF.
Hirano
Yasuhiro
Y
Graduate School of Biostudies, Kyoto University, Yoshida-konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. hirano@lif.kyoto-u.ac.jp
Iwase
Yuka
Y
Ishii
Kohei
K
Kumeta
Masahiro
M
Horigome
Tsuneyoshi
T
Takeyasu
Kunio
K
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002453:Cell Cycle; D004268:DNA-Binding Proteins; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation
D004268:DNA-Binding Proteins; C405329:LEMD3 protein, human; D008565:Membrane Proteins; D009687:Nuclear Proteins