Presentation Information
[SS17-07]Physical mechanisms for shaping organelles
*Masashi Tachikawa1 (1. Yokohama City University (Japan))
Keywords:
organelle morphology,physical modeling
Eukaryotic cells have various functional units made of lipid-bilayer membrane, called organelles. Molecular biology and cell biology have revealed various molecules working on organelles, which allow us to characterize the structure, role and dynamics of organelle. The morphology of organelles shaped by the folded, extruded and invaginated lipid membrane are generated and controlled by these molecules and is believed to be optimized to carry out the cellular function in the crowded intracellular conditions. However, the mechanism to generate and maintain the organelle morphologies are yet to be revealed.
To understand the morphology of organelles, we introduce physical model for describing the deformation of lipid membrane under the existence of various membrane associating proteins and develop computational approaches to describe the physical dynamics of the protein-lipid membrane system. The size of organelles is up to 1 µm much larger than the molecular size. Continuum models are suitable for describing the organelle shapes. We employ a dynamically triangulated surface method to describe the tree dimensional shape of membrane. Here we present our recent studies on Golgi apparatus, mitochondria and endosome. Through these studies we emphasize that the force balances among different energy sources control the organelle morphology, and the relation between molecules and their contributions to energy source modifications are key to understand the molecular mechanism to organize organelle systems.
To understand the morphology of organelles, we introduce physical model for describing the deformation of lipid membrane under the existence of various membrane associating proteins and develop computational approaches to describe the physical dynamics of the protein-lipid membrane system. The size of organelles is up to 1 µm much larger than the molecular size. Continuum models are suitable for describing the organelle shapes. We employ a dynamically triangulated surface method to describe the tree dimensional shape of membrane. Here we present our recent studies on Golgi apparatus, mitochondria and endosome. Through these studies we emphasize that the force balances among different energy sources control the organelle morphology, and the relation between molecules and their contributions to energy source modifications are key to understand the molecular mechanism to organize organelle systems.