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PLEASE NOTE: If a candidate gives a layman's talk, the livestream will start fifteen minutes earlier.

Our bodies are composed of tissues made of trillions of specialized cells that share a core set of machinery. Inside cells, the cytoskeleton (microtubules, actin, and vimentin intermediate filaments) organizes shape and transport. Microtubules act as stiff highways, actin drives movement, and vimentin provides resilience. Organelles such as mitochondria, lysosomes, and the endoplasmic reticulum (ER) depend on these networks and motor proteins for proper positioning and function.

Although we know which kinesins move specific cargo, it remains unclear how different kinesins cooperate to control steady-state organelle distribution, particularly in the context of other cytoskeletal and organelle interactions. To address this, we studied five kinesin motors from the three main families (kinesin-1, -2, and 3), focusing on their roles in cytoskeletal organization and organelle positioning, and on how vimentin filaments, alone and together with microtubules and the ER, shape cell architecture.

Kinesin-2 proved especially important for maintaining the ER at the cell edges. Its removal caused ER retraction and increased ER and microtubule mobility, while lysosomes were largely unaffected. When multiple kinesins were removed simultaneously, lysosomes clustered and became more mobile, while the ER remained stable. These findings show that compartment organization depends strongly on motor activity, not simply on direct organelle contact.

We also developed a tool to reposition vimentin using small molecules or light. Shifting vimentin altered the ER and mitochondria, but only mildly affected actin, microtubules, and lysosomes. Dense ER tubules anchored vimentin at the periphery through linkers such as RNF26, with Nesprin-3 emerging as a candidate. Removing vimentin increased ER mobility, while disrupting ER–microtubule links produced opposite effects.

Altogether, these findings reveal deep interdependence among microtubules, vimentin, and the ER. Their coordinated dynamics maintain cellular architecture and, ultimately, cellular function.