title: Evidence that phosphorylation by the mitotic kinase Cdk1 promotes ICER monoubiquitination and nuclear delocalization.
abstract: In contrast to normal prostatic cells, the transcriptional repressor Inducible cAMP Early Repressor (ICER) is undetected in the nuclei of prostate cancer cells. The molecular mechanisms for ICER abnormal expression in prostate cancer cells remained largely unknown. In this report data is presented demonstrating that ICER is phosphorylated by the mitotic kinase cdk1. Phosphorylation of ICER on a discrete residue targeted ICER to be monoubiquitinated. Different from unphosphorylated, phosphorylated and polyubiquitinated ICER, monoubiquitinated ICER was found to be cytosolic. Taken together, these results hinted on a mechanism for the observed abnormal subcellular localization of ICER in human prostate tumors.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, NJ 07103, USA.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Mémin
authors.forename: Megan
authors.initials: M
authors.lastname: Genzale
authors.forename: Marni
authors.initials: M
authors.lastname: Crow
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Molina
mesh_terms: D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D051786:Cyclic AMP Response Element Modulator / Q000378:metabolism*; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008297:Male; D008938:Mitosis; D010766:Phosphorylation; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D014407:Tumor Cells, Cultured; D054875:Ubiquitination
chemical_list: C497410:CREM protein, human; D051786:Cyclic AMP Response Element Modulator; D016203:CDC2 Protein Kinase