Drosophila in the study of hTBP protein interactions in the development and modeling of SCA17

Gac Med Mex. 2024;160(1):1-8. doi: 10.24875/GMM.M24000845.

Abstract

Background: Protein interactions participate in many molecular mechanisms involved in cellular processes. The human TATA box binding protein (hTBP) interacts with Antennapedia (Antp) through its N-terminal region, specifically via its glutamine homopeptides. This PolyQ region acts as a binding site for other transcription factors under normal conditions, but when it expands, it generates spinocerebellar ataxia 17 (SCA17), whose protein aggregates in the brain prevent its correct functioning.

Objective: To determine whether the hTBP glutamine-rich region is involved in its interaction with homeoproteins and the role it plays in the formation of protein aggregates in SCA17.

Material and methods: We characterized hTBP interaction with other homeoproteins using BiFC, and modeled SCA17 in Drosophila melanogaster by targeting hTBPQ80 to the fly brain using UAS/GAL4.

Results: There was hTBP interaction with homeoproteins through its glutamine-rich region, and hTBP protein aggregates with expanded glutamines were found to affect the locomotor capacity of flies.

Conclusions: The study of hTBP interactions opens the possibility for the search for new therapeutic strategies in neurodegenerative pathologies such as SCA17.

Antecedentes: Las interacciones proteicas participan en una gran cantidad de mecanismos moleculares que rigen los procesos celulares. La proteína de unión a la caja TATA humana (hTBP) interacciona con Antennapedia (Antp) a través de su extremo N-terminal, específicamente a través de sus homopéptidos de glutaminas. Esta región PolyQ sirve como sitio de unión a factores de transcripción en condiciones normales, pero cuando se expande genera la ataxia espinal cerebelosa 17 (SCA17), cuyos agregados proteicos en el cerebro impiden su funcionamiento correcto.

Objetivo: Determinar si la región rica en glutaminas de hTBP interviene en su interacción con homeoproteínas y el papel que tiene en la formación de agregados proteicos en SCA17.

Material y métodos: Se caracterizó la interacción de hTBP con otras homeoproteínas usando BiFC y se modeló SCA17 en Drosophila melanogaster dirigiendo hTBPQ80 al cerebro de las moscas usando UAS/GAL4.

Resultados: Existió interacción de hTBP con homeoproteínas a través de su región rica en glutaminas. Los agregados proteicos de hTBP con las glutaminas expandidas afectaron la capacidad locomotriz de las moscas.

Conclusiones: El estudio de las interacciones de hTBP abre la posibilidad para la búsqueda de nuevas estrategias terapéuticas en patologías neurodegenerativas como SCA17.

Keywords: Homeoproteins; Homeoproteínas; Interacciones proteicas; Protein interactions; SCA17; hTBP.

MeSH terms

  • Animals
  • Brain / metabolism
  • Disease Models, Animal*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster* / metabolism
  • Glutamine / metabolism
  • Humans
  • Peptides / metabolism
  • Protein Aggregates / physiology
  • Spinocerebellar Ataxias* / genetics
  • Spinocerebellar Ataxias* / metabolism
  • TATA-Box Binding Protein* / genetics
  • TATA-Box Binding Protein* / metabolism

Substances

  • polyglutamine

Supplementary concepts

  • Spinocerebellar Ataxia 17