@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 {721, title = {Synaptic activity in serotonergic neurons is required for air-puff stimulated flight in Drosophila melanogaster.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e46405}, abstract = {

BACKGROUND: Flight is an integral component of many complex behavioral patterns in insects. The giant fiber circuit has been well studied in several insects including Drosophila. However, components of the insect flight circuit that respond to an air-puff stimulus and comprise the flight central pattern generator are poorly defined. Aminergic neurons have been implicated in locust, moth and Drosophila flight. Here we have investigated the requirement of neuronal activity in serotonergic neurons, during development and in adults, on air-puff induced flight in Drosophila.

METHODOLOGY/PRINCIPAL FINDINGS: To target serotonergic neurons specifically, a Drosophila strain that contains regulatory regions from the TRH (Tryptophan Hydroxylase) gene linked to the yeast transcription factor GAL4 was used. By blocking synaptic transmission from serotonergic neurons with a tetanus toxin transgene or by hyperpolarisation with Kir2.1, close to 50\% adults became flightless. Temporal expression of a temperature sensitive Dynamin mutant transgene (Shi(ts)) suggests that synaptic function in serotonergic neurons is required both during development and in adults. Depletion of IP(3)R in serotonergic neurons via RNAi did not affect flight. Interestingly, at all stages a partial requirement for synaptic activity in serotonergic neurons was observed. The status of serotonergic neurons was investigated in the central nervous system of larvae and adults expressing tetanus toxin. A small but significant reduction was observed in serotonergic cell number in adult second thoracic segments from flightless tetanus toxin expressing animals.

CONCLUSIONS: These studies show that loss of synaptic activity in serotonergic neurons causes a flight deficit. The temporal focus of the flight deficit is during pupal development and in adults. The cause of the flight deficit is likely to be loss of neurons and reduced synaptic function. Based on the partial phenotypes, serotonergic neurons appear to be modulatory, rather than an intrinsic part of the flight circuit.

}, keywords = {Animals, Cell Count, Central Nervous System, DNA-Binding Proteins, Drosophila melanogaster, Drosophila Proteins, Dynamins, Flight, Animal, Gene Expression Regulation, Developmental, Larva, Potassium Channels, Inwardly Rectifying, Pupa, Saccharomyces cerevisiae Proteins, Serotonergic Neurons, Synaptic Transmission, Tetanus Toxin, Transcription Factors, Transgenes, Tryptophan Hydroxylase}, issn = {1932-6203}, doi = {10.1371/journal.pone.0046405}, author = {Sadaf, Sufia and Birman, Serge and Hasan, Gaiti} }