title: Phosphorylation of CEACAM1 molecule by calmodulin kinase IID in a three-dimensional model of mammary gland lumen formation.
abstract: Carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1), a transmembrane protein, expressed on normal breast epithelial cells is down-regulated in breast cancer. Phosphorylation of Thr-457 on the short cytoplasmic domain isoform (CEACAM1-SF) that is predominant in normal epithelial cells is required for lumen formation in a three-dimensional model that involves apoptosis of the central acinar cells. Calmodulin kinase IID (CaMKIID) was selected as a candidate for the kinase required for Thr-457 phosphorylation from a gene chip analysis comparing genes up-regulated in MCF7 cells expressing wild type CEACAM1-SF compared with the T457A-mutated gene (Chen, C. J., Kirshner, J., Sherman, M. A., Hu, W., Nguyen, T., and Shively, J. E. (2007) J. Biol. Chem. 282, 5749-5760). Up-regulation of CaMKIID during lumen formation was confirmed by analysis of mRNA and protein levels. CaMKIID was able to phosphorylate a synthetic peptide corresponding to the cytoplasmic domain of CEACAM1-SF and was covalently bound to biotinylated and T457C-modified peptide in the presence of a kinase trap previously described by Shokat and co-workers (Maly, D. J., Allen, J. A., and Shokat, K. M. (2004) J. Am. Chem. Soc. 126, 9160-9161). When cell lysates from wild type-transfected MCF7 cells undergoing lumen formation were incubated with the peptide and kinase trap, a cross-linked band corresponding to CaMKIID was observed. When these cells were treated with an RNAi that inhibits CaMKIID expression, lumen formation was blocked by over 90%. We conclude that CaMKIID specifically phosphorylates Thr-457 on CEACAM1-SF, which in turn regulates the process of lumen formation via apoptosis of the central acinar cells.
authors.affiliation: From the Department of Immunology, Beckman Research Institute of City of Hope, Duarte, California 91010.
authors.forename: Tung
authors.initials: T
authors.lastname: Nguyen
authors.forename: Charng-Jui
authors.initials: CJ
authors.lastname: Chen
authors.forename: John E
authors.initials: JE
authors.lastname: Shively
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D017209:Apoptosis / Q000502:physiology; D001596:Benzylamines / Q000494:pharmacology; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000235:genetics / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D018929:Cell Culture Techniques / Q000379:methods; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005260:Female; D006801:Humans; D061986:MCF-7 Cells; D042361:Mammary Glands, Human / Q000033:anatomy & histology / Q000166:cytology*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000235:genetics; D013449:Sulfonamides / Q000494:pharmacology; D000096926:Benzenesulfonamides
chemical_list: D015703:Antigens, CD; D001596:Benzylamines; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D015815:Cell Adhesion Molecules; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D013449:Sulfonamides; C069847:CD66 antigens; C072105:KN 93; D000096926:Benzenesulfonamides; C017967:W 7
keywords: Apoptosis; Breast Cancer; CaMKII; Calmodulin; Cell Adhesion; RNA Interference (RNAi)