title: Time-resolved FT-IR microspectroscopy of protein aggregation induced by heat-shock in live cells.
abstract: Maintaining the correct folding of cellular proteins is essential for preserving cellular homeostasis. Protein dishomeostasis, aberrant protein folding, and protein aggregation are indeed involved in several diseases including cancer, aging-associated, and neurodegenerative disorders. Accumulation of protein aggregates can also be induced from a variety of stressful conditions, such as temperature increase or oxidative stress. In this work, we monitored by Fourier transform-infrared (FT-IR) microspectroscopy the response of live breast cancer MCF-7 and mammary breast adenocarcinoma MDA-MB 231 cell lines to severe heat-shock (HS), caused by the rise of the cellular medium temperature from 37 ± 0.5 °C to 42 ± 0.5 °C. Through the study of the time-evolution of the second derivatives of the spectra and by the 2D correlation analysis of FT-IR absorbance data, we were able to identify a common sudden heat-shock response (HSR) among the two cell lines. The hyperfluidization of mammalian cell membranes, the transient increment of the signal lipids, as well as the alteration of proteome profile were all monitored within the first 40 min of stress application, while the persistent intracellular accumulation of extended β-folded protein aggregates was detected after 40 min up to 2 h. As a whole, this paper offers a further prove of the diagnostic capabilities of FT-IR microspectroscopy for monitoring in real-time the biochemical rearrangements undergone by live cells upon external stimulation.
authors.affiliation: †Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.|‡IOM-CNR, TASC Laboratory, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Mitri
authors.affiliation: †Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Saša
authors.initials: S
authors.lastname: Kenig
authors.affiliation: ‡IOM-CNR, TASC Laboratory, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Coceano
authors.affiliation: †Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Diana E
authors.initials: DE
authors.lastname: Bedolla
authors.affiliation: ‡IOM-CNR, TASC Laboratory, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Tormen
authors.affiliation: ‡IOM-CNR, TASC Laboratory, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.|§MBI, National University of Singapore T-Lab, 5A Engineering Drive 1, Singapore.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Grenci
authors.affiliation: †Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Basovizza, Trieste Italy.
authors.forename: Lisa
authors.initials: L
authors.lastname: Vaccari
mesh_terms: D045744:Cell Line, Tumor; D005260:Female; D018869:Heat-Shock Response; D006358:Hot Temperature; D006801:Humans; D008958:Models, Molecular; D066329:Protein Aggregates; D058767:Protein Unfolding; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D066329:Protein Aggregates