title: Predominance of spliceosomal complex formation over polyadenylation site selection in TDP-43 autoregulation.
abstract: TDP-43 is a nuclear protein involved in many aspects of RNA metabolism. To ensure cellular viability, its expression levels within cells must be tightly regulated. We have previously demonstrated that TDP-43 autoregulation occurs through the activation of a normally silent intron in its 3'-UTR sequence that results in the use of alternative polyadenylation sites. In this work, we analyse which is the dominant event in autoregulation: the recognition of the splice sites of 3'-UTR intron 7 or the intrinsic quality of the alternative polyadenylation sites. A panel of minigene constructs was tested for autoregulation functionality, protein production and subcellular messenger RNA localization. Our data clearly indicate that constitutive spliceosome complex formation across intron 7 does not lead to high protein production but, on the contrary, to lower TDP-43 messenger RNA and protein levels. This is due to altered nucleocytoplasmic distribution of the RNA that is mostly retained in the nucleus and degraded. This study provides a novel in-depth characterization of how RNA binding proteins can autoregulate their own levels within cells, an essential regulatory process in maintaining cellular viability.
authors.affiliation: International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Bembich
authors.forename: Jeremias S
authors.initials: JS
authors.lastname: Herzog
authors.forename: Laura
authors.initials: L
authors.lastname: De Conti
authors.forename: Cristiana
authors.initials: C
authors.lastname: Stuani
authors.forename: S Eréndira
authors.initials: SE
authors.lastname: Avendaño-Vázquez
authors.forename: Emanuele
authors.initials: E
authors.lastname: Buratti
authors.forename: Marco
authors.initials: M
authors.lastname: Baralle
authors.forename: Francisco E
authors.initials: FE
authors.lastname: Baralle
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D057809:HEK293 Cells; D006706:Homeostasis; D006801:Humans; D007438:Introns; D026723:Polyadenylation; D022821:RNA Splice Sites; D012326:RNA Splicing; D034443:RNA Transport; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D017381:Spliceosomes / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D022821:RNA Splice Sites; D012333:RNA, Messenger; D016601:RNA-Binding Proteins