title: ISWI ATP-dependent remodeling of nucleoplasmic ω-speckles in the brain of Drosophila melanogaster.
abstract: Heterogeneous nuclear ribonucleoproteins (hnRNPs) belong to the RNA-binding proteins family. They are involved in processing heterogeneous nuclear RNAs (hnRNAs) into mature mRNAs. These proteins participate in every step of mRNA cycle, such as mRNA export, localization, translation, stability and alternative splicing. At least 14 major hnRNPs, which have structural and functional homologues in mammals, are expressed in Drosophila melanogaster. Until now, six of these hnRNPs are known to be nucleus-localized and associated with the long non-coding RNA (lncRNA) heat shock responsive ω (hsrω) in the omega speckle compartments (ω-speckles). The chromatin remodeler ISWI is the catalytic subunit of several ATP-dependent chromatin-remodeling complexes, and it is an essential factor for organization of ω-speckles. Indeed, in ISWI null mutant, severe defects in ω-speckles structure are detectable. Here, we clarify the role of ISWI in the hnRNPs‒hsrω interaction. Moreover, we describe how ISWI by its remodeling activity, controls hsrω and hnRNPs engagement in ω-speckles. Finally, we demonstrate that the sequestration of hnRNPs in ω-speckles nuclear compartment is a fundamental event in gene expression control and represents a key step in the regulation of several pathways.
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Lo Piccolo
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Attardi
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy.
authors.forename: Rosa
authors.initials: R
authors.lastname: Bonaccorso
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Li Greci
authors.affiliation: Genomix4Life Srl, University of Salerno, Baronissi Campus, Salerno 84081, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Giurato
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy.
authors.forename: Antonia Maria Rita
authors.initials: AMR
authors.lastname: Ingrassia
authors.affiliation: STEBICEF Department, University of Palermo, Palermo 90128, Italy. Electronic address: mconorati@dti.telethon.it.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Onorati
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000166:cytology*; D002467:Cell Nucleus / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004331:Drosophila melanogaster / Q000166:cytology* / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D034441:Heterogeneous-Nuclear Ribonucleoproteins; C086468:ISWI protein; D014157:Transcription Factors; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases
keywords: Chromatin remodelers; Nuclear body; Omega speckles; hnRNPs; lncRNA