Paris Postdoc Seminar – Maria Laura Rojas

Maria Laura Rojas (Université Paris Cité, INSERM U1151, CNRS UMR8253, Institut Necker Enfants Malades, Paris, France) will give the next Paris postdoc seminar on the theme :

Organelle Crosstalk and Mitochondrial Renewal in Metabolic Adaptation to Shear Stress

Abstract:

Kidney epithelial cells play a central role in maintaining body water and electrolytes balance, a function that critically depends on continuous urinary flow to maintain metabolic homeostasis and support kidney differentiation.

Data from our lab have shown that urinary flow activates the autophagic machinery in kidney epithelial cells, promoting lipid droplets (LDs) catabolism and the transfer of free fatty acids to mitochondria. This process, in turn, promotes mitochondrial biogenesis and ATP production through oxidative phosphorylation.

Despite these insights, how mitochondrial remodeling and inter-organelle communication are coordinated during this metabolic transition remains poorly understood. Here, we found that physiological fluid flow triggers mitochondrial membrane remodeling and turnover during shear stress adaptation, suggesting that mitochondrial renewal is essential during metabolic shift.  During mitochondrial specialization, inter-organelle crosstalk occurs, particularly with LDs and the endoplasmic reticulum (ER), where tethering and lipid transfer proteins regulate mitochondrial structure and function.

In this context, we identify a transient stabilization of ER–LD-mitochondria contact sites at early stages of fluid flow, required to mediate fatty acid transfer from LDs to mitochondria during shear stress, highlighting the importance of early organelle membrane mobilization in enabling cellular metabolic adaptation to mechanical cues.