MSCA COFUND PhD@Tec21 - PhD position in Biophysics: Active Bio-Gels in Motion: Unraveling anomalous transport of Nano-Objects

id="offer-description" class="ecl-u-type-heading-2 ecl-u-mt-none ecl-u-mb-l">Offer Description Description of the project . This project will investigate how nanoscale extracellular vesicles travel through the extracellular matrix to deliver their cargo of proteins, DNA and RNA to target cells, within biological tissues. Its aim is to identify the physical mechanisms that let a vesicle cross the interstitial space of tissues, and to determine how cell contractions effectively pump the interstitial fluid through the extracellular matrix and how these flows assist vesicle transport. The central paradox is that vesicles move through fibrous matrices whose pores are much smaller than the vesicles themselves. Since no active, ATP-dependent mechanism has been identified in the extracellular matrix, the only local energy source is cellular contractility. Working Hypothesis . The extracellular matrix undergoes elastic and inelastic deformations over long distances, arising from its nonlinear microstructure and non-local constitutive laws. We therefore hypothesize that traction forces generated by cellular contractions in fibrous tissues facilitate vesicle transport. We propose two potentially synergistic mechanisms: . 1) Local “zipping/unzipping” mechanism. A transient interaction between the vesicle surface and a filament of the extracellular matrix could locally and reversibly open the matrix pores, allowing the vesicle to pass before immediate resealing. This process, occurring wi