Postdoctoral researcher position at the Instituto Superior Técnico (IST) Lisbon
Our lab at the Instituto Superior Técnico – IST is looking for a highly motivated postdoctoral researcher to be hired under a research contract of the scientific project: SingleMolHTTex1 – The aggregation- prone structures of Huntingtin exon 1 at the single-molecule level: Influence of membranes and implications in Huntington’s disease.
Project Summary
The pathological expansion of the polyglutamine (PolyQ) repeat within huntingtin (HTT) protein above a critical threshold length of about 37 glutamines is a hallmark of Huntington’s disease (HD). HTT proteolytic cleavage or aberrant splicing lead to highly toxic HTT exon 1 fragments (HTTex1), which are sufficient to replicate much of HD’s pathology. The precise mechanism by which HTTex1 contributes to neurodegeneration remains elusive but growing evidence support that (i) biological membranes play a key role in this mechanism, and (ii) toxic monomeric and/or oligomeric HTTex1 species, rather than aggregates, are the primary cytotoxic species.
The overall aim of this project is to provide a detailed understanding of the initial steps of HTTex1-lipid interaction. However, this characterization has been exceptionally challenging using ensemble biophysical methods due to the heterogeneous nature of this interaction and the high propensity of HTTex1 to aggregate. To overcome these limitations, a complementary set of single-molecule fluorescence techniques (namely, single-molecule FRET and FCS) will be used to obtain insights into the physical/structural features of aggregation-prone states of HTTex1 at the membrane surface.
The results of this frontier project may assist in the rational design of inhibitors to treat and/or prevent HD.
Type of contract
30-month research contract (not fellowship) according to decree-law No. 57/2016.
Requirements
PhD in Biophysics, Bioengineering, Biotechnology, Biochemistry and Chemistry or related areas.
Supervision
The work will be carried out under the scientific guidance of Dr. Ana M. Melo. For further information, please send an email to anammelo@tecnico.ulisboa.pt
Research Centers
The project will be carried out in the Biological Fluorescence Group (Professor Manuel Prieto) at Centro de Química-Física Molecular – CQFM and Institute for Bioengineering and Biosciences – iBB, Instituto Superior Técnico – IST, in Lisbon (Portugal). Our research team has a wide and well- established expertise in the quantitative application of multi-parametric fluorescence approaches to study lipid-protein interactions, and also single-molecule techniques to investigate molecular interactions and conformational changes in IDPs involved in neurodegeneration. Our lab has state-of-the-art fluorescence instrumentation (picosecond time-resolved fluorescence intensity and anisotropy) and also a SP5 Leica confocal microscope equipped with advanced microscopy techniques (e.g. two-photon microscopy, FCS, FRAP, FLIM, FAIM). This project will also support the implementation of smFRET in Portugal. In addition, iBB is equipped with all required facilities for protein expression/purification.
Selected Publications
- Melo AM, Elbaum-Garfinkle S, Rhoades E (2017) Insights into tau function and dysfunction through single-molecule fluorescence. Methods in Cell Biology 141: 27-44.
- Melo AM, Coraor J, Alpha-Cobb G, Elbaum-Garfinkle S, Nath A, Rhoades E (2016) A functional role for intrinsic disorder in the tau-tubulin complex. Proc. Natl. Acad. Sci. U.S.A. 113: 14336-14341. Highlighted on F1000 Prime.
- Melo AM, Prieto M, Coutinho A (2014) Quantifying lipid-protein interaction by fluorescence correlation spectroscopy (FCS). Methods Mol. Biol. 1076: 575-595.
- Melo AM, Prieto M, Coutinho A (2011) The effect of variable liposome brightness on quantifying lipid-protein interactions using fluorescence correlation spectroscopy. Biochim Biophys Acta- Biomembr. 1808: 2559-2568.
