title: All-trans-retinoic acid inhibits collapsin response mediator protein-2 transcriptional activity during SH-SY5Y neuroblastoma cell differentiation.
abstract: Neurons are highly polarized cells composed of two structurally and functionally distinct parts, the axon and the dendrite. The establishment of this asymmetric structure is a tightly regulated process. In fact, alterations in the proteins involved in the configuration of the microtubule lattice are frequent in neuro-oncologic diseases. One of these cytoplasmic mediators is the protein known as collapsin response mediator protein-2, which interacts with and promotes tubulin polymerization. In this study, we investigated collapsin response mediator protein-2 transcriptional regulation during all-trans-retinoic acid-induced differentiation of SH-SY5Y neuroblastoma cells. All-trans-retinoic acid is considered to be a potential preventive and therapeutic agent, and has been extensively used to differentiate neuroblastoma cells in vitro. Therefore, we first demonstrated that collapsin response mediator protein-2 mRNA levels are downregulated during the differentiation process. After completion of deletion construct analysis and mutagenesis and mobility shift assays, we concluded that collapsin response mediator protein-2 basal promoter activity is regulated by the transcription factors AP-2 and Pax-3, whereas E2F, Sp1 and NeuroD1 seem not to participate in its regulation. Furthermore, we finally established that reduced expression of collapsin response mediator protein-2 after all-trans-retinoic acid exposure is associated with impaired Pax-3 and AP-2 binding to their consensus sequences in the collapsin response mediator protein-2 promoter. Decreased attachment of AP-2 is a consequence of its accumulation in the cytoplasm. On the other hand, Pax-3 shows lower binding due to all-trans-retinoic acid-mediated transcriptional repression. Unraveling the molecular mechanisms behind the action of all-trans-retinoic acid on neuroblastoma cells may well offer new perspectives for its clinical application.
authors.affiliation: Department of Biochemistry, University of Navarra, Pamplona, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Fontán-Gabás
authors.forename: Erik
authors.initials: E
authors.lastname: Oliemuller
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Martínez-Irujo
authors.forename: Carlos
authors.initials: C
authors.lastname: de Miguel
authors.forename: Ana
authors.initials: A
authors.lastname: Rouzaut
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D001483:Base Sequence; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D009447:Neuroblastoma / Q000378:metabolism; D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012323:RNA Processing, Post-Transcriptional; D012689:Sequence Homology, Nucleic Acid; D050656:Transcription Factor AP-2 / Q000378:metabolism; D014158:Transcription, Genetic; D014212:Tretinoin / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D000072041:PAX3 Transcription Factor; C489409:PAX3 protein, human; D051761:Paired Box Transcription Factors; D050656:Transcription Factor AP-2; C095114:collapsin response mediator protein-2; D014212:Tretinoin