Polyamines modulate the subcellular localization of RNA-binding protein HuR through AMP-activated protein kinase-regulated phosphorylation and acetylation of importin alpha1.

@article{Zou2008PolyaminesMT,
  title={Polyamines modulate the subcellular localization of RNA-binding protein HuR through AMP-activated protein kinase-regulated phosphorylation and acetylation of importin alpha1.},
  author={Tongtong Zou and Lan Liu and Jaladanki N Rao and Bernard S. Marasa and Jie Chen and Lan Xiao and Huiping Zhou and Myriam Gorospe and Jian-Ying Wang},
  journal={The Biochemical journal},
  year={2008},
  volume={409 2},
  pages={
          389-98
        }
}
Polyamines are required for maintenance of intestinal epithelial integrity, and a decrease in cellular polyamines increases the cytoplasmic levels of RNA-binding protein HuR stabilizing p53 and nucleophosmin mRNAs, thus inhibiting IEC (intestinal epithelial cell) proliferation. The AMPK (AMP-activated protein kinase), an enzyme involved in responding to metabolic stress, was recently found to be implicated in regulating the nuclear import of HuR. Here, we provide evidence showing that… 

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