title: Drosophila dSAP18 is a nuclear protein that associates with chromosomes and the nuclear matrix, and interacts with pinin, a protein factor involved in RNA splicing.
abstract: SAP18 is a highly conserved protein that was proposed to be involved in multiple cellular processes from autophagy to gene regulation and mRNA processing. In this paper we show that, in Drosophila, dSAP18 is a predominantly nuclear protein that associates to both chromosomes and the nuclear matrix. dSAP18 becomes nuclear early during development, at the onset of cellularization, and remains so all through embryo development. dSAP18 is also nuclear in salivary glands, ovaries and cultured S2 cells. Here we also show that dSAP18 forms a complex with the Drosophila homolog of pinin (dPnn), a protein factor involved in mRNA splicing. dSAP18-dPnn interaction was confirmed in vivo, through co-immunoprecipitation experiments, as well as in vitro, through GST pull-down assays. These results are discussed in the context of the possible functions played by SAP18.
authors.affiliation: Departament de Biologia Molecular i Cellular, Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Parc Científic de Barcelona, Josep Samitier 1-5, 08028, Barcelona, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Costa
authors.forename: Silvia
authors.initials: S
authors.lastname: Canudas
authors.forename: Ivan
authors.initials: I
authors.lastname: Garcia-Bassets
authors.forename: Silvia
authors.initials: S
authors.lastname: Pérez
authors.forename: Irene
authors.initials: I
authors.lastname: Fernández
authors.forename: Ernest
authors.initials: E
authors.lastname: Giralt
authors.forename: Fernando
authors.initials: F
authors.lastname: Azorín
authors.forename: M Lluïsa
authors.initials: ML
authors.lastname: Espinás
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D015815:Cell Adhesion Molecules / Q000502:physiology*; D002467:Cell Nucleus / Q000502:physiology; D002875:Chromosomes; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D004625:Embryo, Nonmammalian; D005260:Female; D047468:Immunoprecipitation; D008969:Molecular Sequence Data; D015530:Nuclear Matrix; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D010053:Ovary; D012326:RNA Splicing / Q000235:genetics / Q000502:physiology*; D012469:Salivary Glands; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
chemical_list: D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D029721:Drosophila Proteins; D009687:Nuclear Proteins; C514330:Pnn protein, Drosophila; D014157:Transcription Factors; C407043:bicoid interacting protein 1, Drosophila