@article {1015, title = {Mechanochemical feedback control of dynamin independent endocytosis modulates membrane tension in adherent cells. [Microfluidics and Microfabrication Facility (INT)]}, journal = {Nat Commun}, volume = {9}, year = {2018}, month = {2018 10 11}, pages = {4217}, abstract = {

Plasma membrane tension regulates many key cellular processes. It is modulated by, and can modulate, membrane trafficking. However, the cellular pathway(s) involved in this interplay is poorly understood. Here we find that, among a number of endocytic processes operating simultaneously at the cell surface, a dynamin independent pathway, the CLIC/GEEC (CG) pathway, is rapidly and specifically upregulated upon a sudden reduction of tension. Moreover, inhibition (activation) of the CG pathway results in lower (higher) membrane tension. However, alteration in membrane tension does not directly modulate CG endocytosis. This requires vinculin, a mechano-transducer recruited to focal adhesion in adherent cells. Vinculin acts by controlling the levels of a key regulator of the CG pathway, GBF1, at the plasma membrane. Thus, the CG pathway directly regulates membrane tension and is in turn controlled via a mechano-chemical feedback inhibition, potentially leading to homeostatic regulation of membrane tension in adherent cells.

}, keywords = {Animals, Biomechanical Phenomena, Cell Adhesion, Cell Membrane, Dynamins, Endocytosis, Feedback, Physiological, Mechanotransduction, Cellular, Mice, Signal Transduction, Temperature, Vinculin}, issn = {2041-1723}, doi = {10.1038/s41467-018-06738-5}, author = {Thottacherry, Joseph Jose and Kosmalska, Anita Joanna and Kumar, Amit and Vishen, Amit Singh and Elosegui-Artola, Alberto and Pradhan, Susav and Sharma, Sumit and Singh, Parvinder P and Guadamillas, Marta C and Chaudhary, Natasha and Vishwakarma, Ram and Trepat, Xavier and Del Pozo, Miguel A and Parton, Robert G and Rao, Madan and Pullarkat, Pramod and Roca-Cusachs, Pere and Mayor, Satyajit} } @article {713, title = {Active remodeling of cortical actin regulates spatiotemporal organization of cell surface molecules.}, journal = {Cell}, volume = {149}, year = {2012}, month = {2012 Jun 08}, pages = {1353-67}, abstract = {

Many lipid-tethered proteins and glycolipids exist as monomers and nanoclusters on the surface of living cells. The spatial distribution and dynamics of formation and breakup of nanoclusters does not reflect thermal and chemical equilibrium and is controlled by active remodeling of the underlying cortical actin. We propose a model for nanoclustering based on active hydrodynamics, wherein cell surface molecules bound to dynamic actin are actively driven to form transient clusters. This consistently explains all of our experimental observations. Using FCS and TIRF microscopy, we provide evidence for the existence of short, dynamic, polymerizing actin filaments at the cortex, a key assumption of the theoretical framework. Our theory predicts that lipid-anchored proteins that interact with dynamic actin must exhibit anomalous concentration fluctuations, and a cell membrane protein capable of binding directly to actin can form nanoclusters. These we confirm experimentally, providing an active mechanism for molecular organization and its spatiotemporal regulation on the plasma membrane.

}, keywords = {Actins, Animals, Cell Line, Tumor, Cell Membrane, CHO Cells, Cricetinae, Cytoskeleton, Humans, Membrane Proteins, Models, Biological, Spectrometry, Fluorescence}, issn = {1097-4172}, doi = {10.1016/j.cell.2012.05.008}, author = {Gowrishankar, Kripa and Ghosh, Subhasri and Saha, Suvrajit and C, Rumamol and Mayor, Satyajit and Rao, Madan} }