title: Tiam1 takes PARt in cell polarity.
abstract: Cell polarity is an essential requirement for the proper tissue development of complex organisms. This is underscored by in vivo studies showing that loss of cell polarity contributes to the formation and progression of tumours. Evolutionary conserved multiprotein complexes, such as the Par3-Par6-aPKC or, in short, the Par polarity complex, regulate the establishment of cell polarity. The small Rho GTPases CDC42 and Rac control the activation of the Par polarity complex. Evidence now implicates the Rac activator Tiam1 as a crucial component of the Par complex in regulating neuronal (axonal) and epithelial (apical-basal) polarity. Our current knowledge places Tiam1 at the centre of a pivotal biological process, the establishment and maintenance of cell polarity, and suggests that deregulation of the Tiam1-Par complex contributes to tumourigenicity.
authors.affiliation: Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
authors.forename: Alexander E E
authors.initials: AE
authors.lastname: Mertens
authors.forename: D Michiel
authors.initials: DM
authors.lastname: Pegtel
authors.forename: John G
authors.initials: JG
authors.lastname: Collard
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D018797:Cell Cycle Proteins / Q000502:physiology*; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology*; D002471:Cell Transformation, Neoplastic; D004846:Epithelial Attachment; D005109:Extracellular Matrix / Q000502:physiology; D020662:Guanine Nucleotide Exchange Factors / Q000502:physiology*; D006801:Humans; D008565:Membrane Proteins / Q000502:physiology*; D008954:Models, Biological; D046912:Multiprotein Complexes / Q000378:metabolism; D009363:Neoplasm Proteins / Q000502:physiology*; D009473:Neuronal Plasticity; D051571:Protein Kinase C-alpha / Q000502:physiology*; D011506:Proteins / Q000502:physiology*; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; D019108:Tight Junctions / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; D046912:Multiprotein Complexes; D009363:Neoplasm Proteins; C509689:PARD3 protein, human; D011506:Proteins; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; C087334:TIAM1 protein, human; D051571:Protein Kinase C-alpha