Biophysical Society Thematic Meeting | Ascona 2026

Mechanobiology of Infection

Wednesday Speaker Abstracts

CONFINED GROWTH INDUCES ROBUST YEAST-TO-HYPHAL TRANSITION IN CANDIDA ALBICANS Morgan Delarue LAAS-CNRS, Toulouse, France Candida albicans is a human commensal fungus which can turn into a pathogen in some cases. It is a dimorphic yeast which exists in an ovaloid yeast form and in an elongated hyphal form. The hyphal form is specialized for invasion within host tissues and immune escape. Growth within a biofilm or in the crypt of the intestine in the case of a loss of mucus are examples of naturally spatially confined growth of Candida albicans. Confined growth leads to the emergence of growth-induced pressure, which compresses the cells and their surroundings. We have designed novel microfluidic devices to study how confined growth can impact Candida albicans physiology. We show that a mild increase in compressive stress triggers a yeast to hyphal transition, in a robust and irreversible way. This transition is controlled by farnesol secretion which constraints in space and time the dimorphic switch. While we have not identified a mechanosensor responsible for the transition, it is possible that it is triggered by the observed inhibition of ribosome biogenesis, which we have recently shown to regulate the yeast-to-hyphal transition (Serrano et al, Nat Microbiol, 2025). Our work has identified a novel stressor that regulates Candida albicans pathogenicity. Spatial confinement and subsequent mechanical compression are found in multiple examples during the life cycle of this fungus. Properly identifying what triggers filamentation in this condition could lead to novel ways of reducing Candida albicans’ pathogenicity.

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