Biophysical Society Thematic Meeting | Riga 2026

Active and Responsive Soft Matter: From Biological to Engineered Systems

Thursday Speaker Abstracts

SHAPING AND MOVING MITOCHONDRIA: THE ROLE OF CYTOSKELETAL FORCES Luciana Bruno 1 ; Agustina Fernández Casafuz 1 ; Anael Zurdo 1 ; Azul Brigante 1 ; María Cecilia De Rossi 2 ; Marina Valdora 1 ; Mariela Sued 1 ; Alejandro Monastra 3 ; 1 CONICET - Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Instituto de Cálculo (IC), Buenos Aires, Argentina 2 CONICET - Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica (IQUIBICEN), Buenos Aires, Argentina 3 Universidad Nacional de General Sarmiento, Instituto de Ciencias, Los Polvorines, Argentina Mitochondrial shape and motility emerge from the interplay between active cytoskeletal forces and thermal fluctuations in the crowded cellular environment. In our group, we investigate the mechanical principles governing mitochondrial dynamics by combining high-resolution live-cell imaging with quantitative physical modeling. Tracking individual mitochondria in Xenopus laevis melanophore cells, we analyze transport dynamics, shape fluctuations, and mechanically induced jittering. Our results identify microtubules as the dominant mechanical scaffold driving long-range transport, elongation, and force transmission, while actin filaments impose constraints on mitochondrial mobility and morphology. We introduce a minimally invasive quantitative method to detect localized active force impulses acting on mitochondria and to separate them from background thermal noise. Our findings frame mitochondrial behavior as an out-of-equilibrium mechanical process governed by cytoskeletal force transmission, highlighting the role of intracellular mechanics in organelle dynamics.

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