The edge of a cell: a living fabric by Satyajit Mayor скачать в хорошем качестве

The edge of a cell: a living fabric by Satyajit Mayor

Foundation Day Lectures The edge of a cell: a living fabric Speaker: Satyajit Mayor (NCBS-TIFR, Bengaluru) Date: 13 December 2022, 17:30 to 19:00 Venue: Chandrasekhar Auditorium, ICTS   The edge of a living cell is a flimsy four nanometer wide lipidic membrane bilayer that separates the outside of the cell from the inside. Its structure and organization has been the subject of research for close to a hundred years. In fact, 50 years ago almost to date, a unifying model called the fluid-mosaic model was proposed to provide an explanation for some of its physical and chemical properties. This model declared that the plasma membrane was a complex mixture of lipids and proteins which were well mixed. Today we recognize that the membrane is far from being well-mixed. Its organization, form and physico-chemical properties are impacted not only by its dynamically maintained composition but by its interaction with the extracellular environment as well as the cortical cytoskeleton that it is draped over. My talk will describe the evolution of our thinking about the membrane and provide a perspective on how we see this part of the cell behave as an active actin membrane composite, and how as a uniquely living material it influences many decisions that the cell must make. Table of Contents (powered by https://videoken.com) 0:00:00 The Edge of a Cell: A Living Fabric 0:08:31 The active actin-membrane composite team 0:11:41 History of cell membrane structure 0:15:55 Where do these lipids come from? 0:16:07 Evolutionary Tree of Life 0:17:21 Where do these phospholipids come from? 0:19:15 (Revised) Evolutionary Tree of Life 0:19:53 O2 emissions Climate Change? 0:22:37 Revised Evolutionary Tree of Life 0:23:00 The second encounter : 'Raft' phase of the cell membrane: 0:27:19 Composition is tightly controlled 0:27:38 Possible Phases in cell membranes 0:29:37 Organization of Cell Surface Molecules 0:30:34 Tools to Study Organization of Cell Surface Molecules 0:34:16 Models of membrane organization: 0:35:07 Membrane template by cortical actin: Aki Kusumi and the Membrane Skeleton Fence Model 0:36:33 The Third Encounter - Physics of active systems Membrane template by dynamic cortical actin: 0:36:55 A Theoretical Framework 0:37:54 Active dynamics of cortical action filaments 0:38:35 Membrane template by dynamic cortical actin: active mechanics 0:39:15 Model recapitulates key features of cell experiments 0:39:44 Model recapitulates key features of cell experiments and also makes predictions 0:43:07 How do GPI-anchored proteins couple across the bilayer? 0:46:18 GPI-anchored protein clusters correlate with /o domains 0:46:19 The State of Membrane Lipids 0:48:35 Membrane heterogeneity as a consequence of active mechanics of cortical action 0:49:00 Cell surface is a membrane - action cortex composite 0:50:20 A sensory system 0:51:40 Temporal evolution of GPI-anchored proteins nano-cluster during Integrin activation 0:52:20 Signalling Receptors sculpt their local membrane environment 0:53:05 Parts List : Evolutionary Antecedents 0:53:37 Active composite membranes have been active for long time 0:55:21 Mechano-sensing via the creation membrane domains 0:56:28 Membrane Lipid Organization, Sorting and Protein Confirmation: 0:57:17 A new solvatochromic probe for membrane order 0:58:02 Signalling receptors sculpt their local membrane environment for functional purposes- 0:58:38 The structure and organization of cell membranes: 1:00:01 In Conclusion 1:02:52 Q&A