title: N-terminally truncated BAF57 isoforms contribute to the diversity of SWI/SNF complexes in neurons.
abstract: The SWItch/Sucrose NonFermentable, a nucleosome remodeling complex (SWI/SNF) chromatin-remodelling complexes act upon the nucleosomal structure and regulate transcription, replication, repair of chromatin and splicing. In this study, we present evidence that human, mouse and rat genes encoding one of the SWI/SNF complex subunits, BAF57, undergo neuron-specific splicing of exons II, III and IV. Alternative splicing yields in at least three isoforms of BAF57 protein that have truncated N-termini (N-BAF57s). The transcripts encoding N-BAF57 isoforms are predominantly expressed in the nervous system. The biochemical fractionation data supported by the results of the co-immunoprecipitation analysis show that N-BAF57 isoforms associate into protein complexes together with Brg1, Brm, BAF155 and BAF170. Transient over-expression of N-BAF57 isoforms in non-neural cells affects the level of expression of certain neuron-restrictive silencer element-containing genes. Together these data suggest that neuronal isoforms of BAF57 contribute to functional SWI/SNF complexes regulating neurogenesis.
authors.affiliation: Protobios LLC, Tallinn, Estonia.
authors.forename: Anna
authors.initials: A
authors.lastname: Kazantseva
authors.forename: Mari
authors.initials: M
authors.lastname: Sepp
authors.forename: Jekaterina
authors.initials: J
authors.lastname: Kazantseva
authors.forename: Helle
authors.initials: H
authors.lastname: Sadam
authors.forename: Priit
authors.initials: P
authors.lastname: Pruunsild
authors.forename: Tõnis
authors.initials: T
authors.lastname: Timmusk
authors.forename: Toomas
authors.initials: T
authors.lastname: Neuman
authors.forename: Kaia
authors.initials: K
authors.lastname: Palm
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001921:Brain / Q000166:cytology; D002478:Cells, Cultured; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004265:DNA Helicases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004622:Embryo, Mammalian; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods; D008545:Melanoma; D051379:Mice; D009447:Neuroblastoma; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D009687:Nuclear Proteins / Q000378:metabolism; D010446:Peptide Fragments; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013347:Subcellular Fractions / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010446:Peptide Fragments; D020033:Protein Isoforms; D012333:RNA, Messenger; C084011:SMARCA2 protein, human; C101682:SMARCC2 protein, human; C504738:SMARCE1 protein, human; D014157:Transcription Factors; C084108:SMARCA4 protein, human; D004265:DNA Helicases