Proteostasis and Proteolytic Signalling

PP_Photo - Cópia (2)

Paulo Pereira

Principal Investigator
Habilitation by the Faculty of Medicine, University of Coimbra
PhD in Cell Biology, University of Coimbra
Biochemistry, University of Coimbra

Short Bio


Campus Sant'Ana
Pólo de Investigação, NMS, UNL
Rua Câmara Pestana, nº 6
Lab 3.16
1150-082 Lisboa, Portugal

Phone: (+351) 218 803 101 (Ext. 26043)
Lab Ext: 26013
E-mail: ppereira(at)

Main interests

During ageing and disease cells are exposed to increased levels of stress that damages various biomolecules, including cellular proteins.
Accumulation of damaged or otherwise obsolete proteins is often toxic and can lead or contribute to cell damage during ageing or disease. Thus, it is critical that cells efficiently repair or dispose of such proteins. Elimination of damaged proteins is tightly regulated and involves a variety of proteases and proteolytic systems, including the ubiquitin proteasome system (UPP) and various forms of autophagy.


In the last few years it became apparent that proteolytic systems have unanticipated signalling functions in the cell. For example, targeting of protein substrates by ubiquitin targets not only proteins for proteasomal degradation but it also regulates subcellular trafficking and DNA transcription.
Our group is interested in exploring non-canonical functions for proteolytic signalling and in the putative crosstalk between the various proteolytic systems in the cell. We want to understand how cooperation between proteolytic systems can contribute to the fine-tuning of key regulatory proteins under specific conditions. For instance, we have shown that the HIF-1alpha protein, a transcription factor that helps tissues and organs to cope with hypoxia, can be regulated by a complex cross-talk between UPP and new particular form of autophagy called Chaperon-Mediated Autophagy (CMA).
We have also shown that intercellular communication through gap-junctions can be fine-tuned by a complex molecular interplay involving UPP, autophagy and specific deubiquitinating enzymes that target the Gap-junction protein connexin 43 (Cx43). By pursuing these studies we have identified new targets for CMA and for macroautophagy (such as HIF and Cx43). We have also identified critical molecular players, such as co-chaperone CHIP that mediates triage decisions between the proteolytic systems (UPP and CMA) and protein folding.

esquema final autofagia + UCH-L1

In close collaboration with our colleagues at CNC.IBILI we have used various cell and animal models to assess the physiological relevance and pathophysiological implications of the regulation of proteolysis and disruption of proteostasis in health and disease.
For example we have shown that tight regulation of proteostasis and crosstalk between proteolytic systems play key roles in diseases such as Age Related Macular Degeneration, diabetic retinopathy cardiac isquemia, tumour growth etc.

Our goal is to continue to elucidate unanticipated roles for key regulators of the cross-talk between proteolytic systems in the cell, to identify key molecular players and new signalling functions for proteolysis, thus opening new avenues for the understanding and treatment of diseases associated with deregulation of proteostasis, including age-related diseases.



PTDC/SAU-ORG/119296/2010 - Unravelling the molecular events of gap junction remodelling in ischemic heart

FCT- PTDC/SAU-ORG/118694/2010 - An animal model for age-related changes in proteostasis

PTDC/SAU-ORG/113542/2009 - Tumorigenesis as a working model for the physiological role of HIF-1alpha degradation by chaperone-mediated autophagy

PTDC/SAU-OSM/67498/2006 - A new route for endothelial dysfunction on diabetes: From phenotypes to molecules

Selected Publications
  • Martins-Marques T, Isabel Anjo S, Pereira P, Manadas B, Girao H. Interacting network of the gap junction protein connexin43 is modulated by ischemia and reperfusion in the heart. Mol Cell Proteomics, August 27, 2015, doi:10.1074/mcp.M115.052894.
  • Soares AR, Martins-Marques T, Ribeiro-Rodrigues T, Ferreira JV Catarino S, Pinho MJ, Zuzarte M, Anjo SI, Manadas B, Sluijter JPG, Pereira P, Girao H. Gap junctional protein Cx43 is involved in the communication between extracellular vesicles and mammalian cells. Sci Reports 2015, 5:13243.
  • Ferreira JV, Soares A, Ramalho JS, Pereira P, Girao H. K63 linked ubiquitin chain formation is a signal for HIF1A degradation by Chaperone-Mediated Autophagy. Sci Reports 2015, 5:10210
  • Martins-Marques T, Catarino S, Marques C, Matafome P, Ribeiro-Rodrigues T, Pereira P, Girão H. Heart ischemia results in Connexin43 ubiquitination localized at the intercalated discs. Biochimie 2015, 112:196-201
  • Ribeiro-Rodrigues T, Catarino S, Pinho MJ, Pereira P and Girao H. Connexin 43 ubiquitination determines the fate of gap junctions: restrict to survive. Biochem Soc Trans 2015, 3:471-5
  • Martins-Marques T, Catarino S, Marques C, Pereira P, Girão H. To beat or not to beat: degradation of Cx43 imposes the heart rhythm. Biochem Soc Trans 2015, 43:476-81
  • Martins-Marques T, Catarino S, Zuzarte M, Marques C, Matafome P, Pereira P, Girão H. Ischemia-induced autophagy leads to degradation of gap junction protein Connexin43 in cardiomyocytes. Biochem J. 2015, 467(2):231-45
  • Martins-Marques T, Ribeiro-Rodrigues T, Pereira P, Codogno P, Girao H. Autophagy and Ubiquitination in Cardiovascular Diseases. DNA Cell Biol. 2015, 34(4):243-51
  • Ribeiro-Rodrigues T, Catarino S, Marques C, Ferreira J, Marques T, Pereira P, Girao H. AMSH-mediated deubiquitination of Cx43 regulates internalization and degradation of gap junctions, FASEB J 2014, 28:4629-41
  • Simões-Correia J, Silva DI, Melo S, Figueiredo J, Caldeira J, Pinto MT, Girão H, Pereira P, Seruca R. DNAJB4 molecular chaperone distinguishes WT from mutant E-cadherin, determining their fate in vitro and in vivo. Hum Mol Genet 2014, 23:2094-2105
  • Ferreira JV, Fofo H, Bejarano E, Figueira Bento C, Ramalho JS, Girao H, Pereira P. CHIP/STUB1 is required for HIF-1A degradation by Chaperone-Mediated Autophagy. Autophagy 2013,9:1349-1366.
  • Bejarano E*, Girao H*, Yuste A, Patel B, Marques C, Spray D, Cuervo AM, Pereira P. Autophagy modulates dynamics of connexins at the plasma membrane in an ubiquitin-dependent manner. Mol Biol Cell 2012, 23:2156-69
  • Catarino SM, Ramalho JS, Marques C, Pereira PC, Girao H. Ubiquitin-mediated internalization of Connexin43 is independent on the canonical endocytic tyrosine-sorting signal. Biochem J. 2011, 437:255-67.
  • Girão H, Catarino S and Pereira P. Eps15 interacts with ubiquitinated Cx43 and mediates its internalization. Exp Cell Res. 2010, 315:3587-3597.
  • Carvalho AN, Marques C, Rodrigues E, Henderson CJ, Wolf CR, Pereira P, Gama MJ. Ubiquitin-proteasome system impairment and MPTP-induced oxidative stress in the brain of C57BL/6 wild-type and GSTP knockout mice. Mol Neurobiol. 2013 Apr;47(2):662-72. doi: 10.1007/s12035-012-8368-4. Epub 2012 Nov 6.
  • Francisco V, Costa G, Figueirinha A, Marques C, Pereira P, Miguel Neves B, Celeste Lopes M, García-Rodríguez C, Teresa Cruz M, Teresa Batista M. Anti-inflammatory activity of Cymbopogon citratus leaves infusion via proteasome and nuclear factor-κB pathway inhibition: contribution of chlorogenic acid. J Ethnopharmacol. 2013 Jun 21;148(1):126-34. doi: 10.1016/j.jep.2013.03.077. Epub 2013 Apr 10.
  • Catarino S, Bento CF, Brito A, Murteira E, Fernandes AF, Pereira P. Regulation of the expression of interleukin-8 induced by 25-hydroxycholesterol in retinal pigment epithelium cells. Acta Ophthalmol. 2012 Jun;90(4):e255-63. doi: 10.1111/j.1755-3768.2011.02350.x. Epub 2012 Feb 7.


  • Henrique Girão; CNC.IBILI, University of Coimbra, Portugal
  • Claudia Pereira, CNC.IBILI, University of Coimbra, Portugal
  • Paula Moreira, CNC.IBILI, University of Coimbra, Portugal
  • Teresa Cruz, CNC.IBILI, University of Coimbra, Portugal
  • Ana Maria Cuervo, Albert Einstein College of Medicine, NY, USA
  • Alan Prescott, University of Dundee, UK
  • Alan Tayllor, USDA – Tufts University, Boston, USA
  • Fu Shang Tufts University, Boston, USA
  • Michael Clague, ITM, University of Liverpool, Liverpool, UK
  • Ehud Cohen, Hebrew University, Faculty of Medicine, Jerusalem, Israel

Open Positions

If you would like to apply for a position please contact Paulo Pereira (