title: LIM-only protein FHL3 interacts with CDC25B2 phosphatase.
abstract: LIM domain proteins are important regulators of the growth, determination, and differentiation of cells. In this report, FHL3 (human four-and-a-half LIM-only protein 3) is shown to interact with human phosphatase CDC25B, a cell cycle regulator involved in the control of G2/M. We found that this interaction was specific to the CDC25B2 isoform. Deletion and point mutation studies indicated that the second LIM domain of FHL3 was essential for this interaction. FRET experiments in C2C12 cells showed that, although both proteins were colocated in the cytoplasm and the nucleus, they interacted only in the nucleus. Finally, we showed that FHL3 binding impaired neither CDC25B2 phosphatase activity nor its localization. Further work is now needed to elucidate the consequences of this interaction on myoblast fate decision and cycle control.
authors.affiliation: Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération, CNRS UMR5088, Université Paul Sabatier, IFR 109 "Exploration Fonctionnelle des Génomes," 118 Route de Narbonne, Batiment 4R3b1-31062, Toulouse Cedex, France. mils@cict.fr
authors.forename: Valérie
authors.initials: V
authors.lastname: Mils
authors.forename: Simon Ming Yuen
authors.initials: SM
authors.lastname: Lee
authors.forename: Willy
authors.initials: W
authors.lastname: Joly
authors.forename: Eric Wong Chi
authors.initials: EW
authors.lastname: Hang
authors.forename: Véronique
authors.initials: V
authors.lastname: Baldin
authors.forename: Mary Miu Yee
authors.initials: MM
authors.lastname: Waye
authors.forename: Bernard
authors.initials: B
authors.lastname: Ducommun
authors.forename: Stephen Kwok Wing
authors.initials: SK
authors.lastname: Tsui
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D022001:Focal Adhesions / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D060588:LIM Domain Proteins; D011485:Protein Binding; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D020687:cdc25 Phosphatases / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; C117563:FHL3 protein, human; D018398:Homeodomain Proteins; D047908:Intracellular Signaling Peptides and Proteins; D060588:LIM Domain Proteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; C517008:CDC25B protein, human; D020687:cdc25 Phosphatases