Novel peptides aimed at interacting with the intracellular domain of dopamine receptor type 2

• Autor(a) principal: Vicente, Inês Teodósio
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/162947
• topic: GPCRs; D2R; G-protein; peptides; TRUPATH; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química

Degenerative diseases of the Central Nervous System (CNS) are the result of the pro- gressive loss of the ability to respond to nerve impulses, most of which still have no cure. One of the biological structures involved in some pathologies is the dopaminergic (DA) system, with different pathways being mediated by G-protein-coupled receptors (GPCRs), such as the case of dopamine receptors (DRs). Mutations in DRs, namely dopamine D2 receptors (D2R), have been associated with dopaminergic dysregulation, which is consequently associated with var- ious neurological and psychiatric diseases. As a result, modulation of this pathway, using, for example, D2R synthetic antagonists, could result in novel treatments and/or improvement of the quality of life of patients. The work in this thesis aimed at the design of peptides able to interact with the intracel- lular D2R/G-protein interface, which might result in the development of peptide-based com- pounds with therapeutic potential. Some of the peptides contain a cell penetrating sequence (CPP) that will allow translocation of the targeting peptides through the cell membrane. In addition, we aimed to biologically assay peptide-D2R interaction using the TRUPATH assay. After several attempts, we prepared four peptides by Solid Phase Peptide Synthesis (SPPS) on a Wang-PEG resin, namely pep_Gs (FNDCRDIIQRMHLRQYELL), pep_GsTAT (YGRK- KRRQRRR-FNDCRDIIQRMHLRQYELL), pep_Gi12 (FDAVTDVIIKNNLKDCGLF) and pep_Gi12TAT (YGRKKRRQRRR-FDAVTDVIIKNNLKDCGLF). After purification by reversed-phase high perfor- mance liquid chromatography (RP-HPLC), the peptides were characterized by electrospray ion- ization mass spectrometry (ESI-MS). The biological activity of the peptides will be evaluated by the TRUPATH assay after setting up and validation of the assay test method in the laboratory.