title: Interactomic analysis of REST/NRSF and implications of its functional links with the transcription suppressor TRIM28 during neuronal differentiation.
abstract: RE-1 silencing transcription factor (REST) is a transcriptional repressor that regulates gene expression by binding to repressor element 1. However, despite its critical function in physiology, little is known about its interaction proteins. Here we identified 204 REST-interacting proteins using affinity purification and mass spectrometry. The interactome included proteins associated with mRNA processing/splicing, chromatin organization, and transcription. The interactions of these REST-interacting proteins, which included TRIM28, were confirmed by co-immunoprecipitation and immunocytochemistry, respectively. Gene Ontology (GO) analysis revealed that neuronal differentiation-related GO terms were enriched among target genes that were co-regulated by REST and TRIM28, while the level of CTNND2 was increased by the knockdown of REST and TRIM28. Consistently, the level of CTNND2 increased while those of REST and TRIM28 decreased during neuronal differentiation in the primary neurons, suggesting that CTNND2 expression may be co-regulated by both. Furthermore, neurite outgrowth was increased by depletion of REST or TRIM28, implying that reduction of both REST and TRIM28 could promote neuronal differentiation via induction of CTNND2 expression. In conclusion, our study of REST reveals novel interacting proteins which could be a valuable resource for investigating unidentified functions of REST and also suggested functional links between REST and TRIM28 during neuronal development.
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea.
authors.forename: Namgyu
authors.initials: N
authors.lastname: Lee
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea.
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 3E1, Canada.
authors.forename: Ghazal
authors.initials: G
authors.lastname: Haddad
authors.affiliation: Donnelly Centre, Departments of Molecular Genetics and Computer Science, University of Toronto, Toronto, Ontario M5S 3E1, Canada.|Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.
authors.forename: Dae-Kyum
authors.initials: DK
authors.lastname: Kim
authors.affiliation: Pohang Center for Evaluation of Biomaterials, Pohang, Gyeonbuk, Korea.|Department of Veterinary Medicine, Kyungpook, National University, Daegu, Republic of Korea.
authors.forename: Seon-Min
authors.initials: SM
authors.lastname: Park
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea.
authors.forename: Sang Ki
authors.initials: SK
authors.lastname: Park
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea.|Department of Integrative Biosciences &Biotechnology, Pohang, Gyeongbuk, Republic of Korea.
authors.forename: Kwan Yong
authors.initials: KY
authors.lastname: Choi
mesh_terms: D000818:Animals; D051177:Catenins / Q000378:metabolism*; D002454:Cell Differentiation; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D063990:Gene Ontology; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D009474:Neurons / Q000166:cytology* / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D000076183:Tripartite Motif-Containing Protein 28 / Q000235:genetics / Q000378:metabolism*; D000095002:Delta Catenin; D000099229:RE1-Silencing Transcription Factor
chemical_list: D051177:Catenins; D012097:Repressor Proteins; D000076183:Tripartite Motif-Containing Protein 28; D000095002:Delta Catenin; D000099229:RE1-Silencing Transcription Factor; C101116:TRIM28 protein, human