title: FIP-2, an IkappaB-kinase-gamma-related protein, is associated with the Golgi apparatus and translocates to the marginal band during chicken erythroblast differentiation.
abstract: Using an antiserum directed against marginal band associated proteins of chicken erythrocytes we isolated clones encoding the chicken homolog of 14.7K-interacting protein 2 (FIP-2), a protein potentially involved in tumor necrosis factor-alpha/nuclear factor-kappaB signaling, from a chicken erythroblast cDNA library. We found that chicken FIP-2 was expressed in a variety of tissues and cell types, but unlike its human counterpart, alternative splicing does not appear to take place. Analysis of intracellular localization revealed that FIP-2 was concentrated at the Golgi apparatus in most cells. Perturbation of the Golgi structure without loss of Golgi function (by treatment with nocodazole) resulted in a retention of FIP-2 at the dispersed Golgi fragments. In contrast, disruption of both Golgi structure and function (by brefeldin A) led to a loss of FIP-2 from Golgi membranes. Remarkably, during erythroblast differentiation FIP-2 was found to translocate from the Golgi to the marginal band. Our results support the hypothesis of a function of the Golgi apparatus in signal transduction. Moreover, our results raise the possibility that the marginal band of chicken erythrocytes, in addition to its role in morphogenesis, has a function in signal transduction and that FIP-2 is in some way involved in its formation.
authors.affiliation: Institute of Biochemistry and Molecular Cell Biology, Vienna Biocenter, University of Vienna, Dr. Bohr-Gasse 9, A-1030 Vienna, Austria.
authors.forename: Heike
authors.initials: H
authors.lastname: Stroissnigg
authors.forename: Marion
authors.initials: M
authors.lastname: Repitz
authors.forename: Angelina
authors.initials: A
authors.lastname: Miloloza
authors.forename: Irena
authors.initials: I
authors.lastname: Linhartova
authors.forename: Hartmut
authors.initials: H
authors.lastname: Beug
authors.forename: Gerhard
authors.initials: G
authors.lastname: Wiche
authors.forename: Friedrich
authors.initials: F
authors.lastname: Propst
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism* / Q000502:physiology; D002454:Cell Differentiation; D002645:Chickens; D004900:Erythroblasts / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism* / Q000502:physiology; D051550:I-kappa B Kinase; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000378:metabolism* / Q000502:physiology; D008969:Molecular Sequence Data; D017346:Protein Serine-Threonine Kinases; D021381:Protein Transport; D016415:Sequence Alignment; D015398:Signal Transduction
chemical_list: D002352:Carrier Proteins; D017346:Protein Serine-Threonine Kinases; D051550:I-kappa B Kinase