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| Author(s): |
Jéssica Christina Lóis de Oliveira Campos
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2016-08-31 |
| Examining board members: |
Ana Carolina Migliorini Figueira;
Sandra Martha Gomes Dias;
Francisco de Assis Rocha Neves;
Fernanda Apareceida Helena Batista;
Célia Regina Nogueira
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| Advisor: | Ana Carolina Migliorini Figueira |
| Abstract | |
Nuclear Receptors (NRs) are proteins activated by small hydrophobic molecules that act directly in regulation of gene expression. Thyroid Hormone Receptors (TRs) are NRs involved in maintaining metabolic rates, oxygen consumption and have unique functions in different organs. There are two isoforms of TRs: TR? and TR?, each one has different expression among human tissues. The small hydrophobic molecules responsible for TRs regulation are triiodothyronine (T3) and thyroxine (T4) hormones. Nowadays, a deeply understanding of indirect non-classical transcription regulation by TRs could lead to a better mapping of the main differences between normal and pathological states of the cell. To do so, we performed screenings in yeast two-hybrid system (y2h) and immunoprecipitation (IP) followed by Mass Spectrometry (LC-MS/MS) to identify novel interactors for TRs and to elucidate possible differences between both isoforms plus and minus T3. The results showed TR? binding a superior number of interactors in comparison with TR?. In second place, treatment with T3 decreases TR expression. In third place, we build interactomes for TRs and we classified the protein candidates by biological process (BP). Following, important candidates from cell cycle regulation BP were confirmed by Co-immunoprecipitation (Co-IP) with TRs. One of those interactions, TR-PDI was further investigated and our results showed that PDI changes TR-gene regulation in reporter gene assays. In addition, PDI knockdown alters expression of some genes. In Biophysical Assays we characterized TR-PDI complex and measure binding affinities (Kd). We observed that complex formation do not change coactivator recruitment. Finally, we built in silico models in order to elucidate TR-PDI possible interfaces of interaction. Overall, we suggest that TRs have important roles in less studied pathways, as cell cycle regulation, and TRs could be regulated by redox mechanism to change gene expression (AU) | |
| FAPESP's process: | 11/23659-2 - Interaction between nuclear receptors TR (thyroid hormone receptor), PPAR (Peroxissome Proliferator-Activated Receptor) and other cell proteins |
| Grantee: | Jéssica Christina Lóis de Oliveira Campos |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |