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Membrane remodeling is a critical process for many membrane trafficking events, including clathrin-mediated endocytosis. Several molecular mechanisms for protein-induced membrane curvature have been described in some detail. Contrary, the effect that the physico-chemical properties of the membrane have on these processes is far less well understood. Here, we show that the membrane binding and curvature-inducing ENTH domain of epsin1 is regulated by phosphatidylserine (PS). ENTH binds to membranes in a PI(4,5)P2-dependent manner but only induces curvature in the presence of PS. On PS-containing membranes, the ENTH domain forms rigid homo-oligomers and assembles into clusters. Membrane binding and membrane remodeling can be separated by structure-to-function mutants. Such oligomerization mutants bind to membranes but do not show membrane remodeling activity. In vivo, they are not able to rescue defects in epidermal growth factor receptor (EGFR) endocytosis in epsin knock-down cells. Together, these data show that the membrane lipid composition is important for the regulation of protein-dependent membrane deformation during clathrin-mediated endocytosis. Electronic supplementary material The online version of this article (10.1007/s00018-020-03647-z) contains supplementary material, which is available to authorized users.

Variations in atmosphere oxygen and ocean sulfate concentrations through time are regarded as important controls on the cycles of sediment-hosted and volcanic-hosted ore deposits. However, estimates of atmosphere oxygen in the Proterozoic have been frustrated by the lack of a direct measurement method and conflicting evidence from various proposed geochemical proxies. Studies in the 1970s to 1990s suggested a relatively oxygenated atmosphere (> 3 wt% O2) in the Proterozoic. However, since the late 1990s, new proxies and modelling have suggested very much lower levels of oxygen (

Fluoride contamination in the groundwater has got great attention in last few decades due to their toxicity, persistent capacity and accumulation in human bodies. There are several sources of fluoride in the environment and different pathways to enter in the drinking water resources, which is responsible for potential effect on human health. Presence of high concentration of fluoride ion in groundwater is a major issue and it makes the water unsuitable for drinking purpose. Availability of fluoride in groundwater indicates various geochemical processes and subsurface contamination of a particular area. Fluoride-bearing aquifers, geological factors, rate of weathering, ion-exchange reaction, residence time and leaching of subsurface contaminants are major responsible factors for availability of fluoride in groundwater. In India, several studies have reported that the groundwater of several states are contaminated with high fluoride. The undesirable level of fluoride in groundwater is one of the most natural groundwater quality problem, which affects large portion of arid and semiarid regions of India. Rajasthan, Andhra Pradesh, Telangana, Tamil Nadu, Gujarat, and West Bengal are the relatively high-fluoride-contaminated states in India. Chronic ingestion of high doses of fluoride-rich water leads to fluorosis on human and animal. Over 66 million Indian populations are at risk due to excess fluoride-contaminated water. Therefore, groundwater contamination subject to undesirable level of fluoride needs urgent attention to understand the role of geochemistry, hydrogeology and climatic factors along with anthropogenic inputs in fluoride pollution.

BackgroundLight and carbon are two important interacting signals affecting plant growth and development. The mechanism(s) and/or genes involved in sensing and/or mediating the signaling pathways involving these interactions are unknown. This study integrates genetic, genomic and systems approaches to identify a genetically perturbed gene network that is regulated by the interaction of carbon and light signaling in Arabidopsis.ResultsCarbon andlightinsensitive (cli) mutants were isolated. Microarray data fromcli186is analyzed to identify the genes, biological processes and gene networks affected by the integration of light and carbon pathways. Analysis of this data reveals 966 genes regulated by light and/or carbon signaling in wild-type. Incli186, 216 of these light/carbon regulated genes are misregulated in response to light and/or carbon treatments where 78% are misregulated in response to light and carbon interactions. Analysis of the gene lists show that genes in the biological processes "energy" and "metabolism" are over-represented among the 966 genes regulated by carbon and/or light in wild-type, and the 216 misregulated genes incli186. To understand connections among carbon and/or light regulated genes in wild-type and the misregulated genes incli186, the microarray data is interpreted in the context of metabolic and regulatory networks. The network created from the 966 light/carbon regulated genes in wild-type, reveals thatcli186is affected in the light and/or carbon regulation of a network of 60 connected genes, including six transcription factors. One transcription factor, HAT22 appears to be a regulatory "hub" in thecli186network as it shows regulatory connections linking a metabolic network of genes involved in "amino acid metabolism", "C-compound/carbohydrate metabolism" and "glycolysis/gluconeogenesis".ConclusionThe global misregulation of gene networks controlled by light and carbon signaling incli186indicates that it represents one of the first Arabidopsis mutants isolated that is specifically disrupted in the integration of both carbon and light signals to control the regulation of metabolic, developmental and regulatory genes. The network analysis of misregulated genes suggests thatCLI186acts to integrate light and carbon signaling interactions and is a master regulator connecting the regulation of a host of downstream metabolic and regulatory processes.

Aerial photographs and LANDSAT images have been used in conjunction with existing topographical and geological information to prepare a land unit map of the Piedmont plain of the Himalaya between the Tista and Jaldhaka Rivers, in parts of Darjeeling Jaiguri districts, West Bengal. Such study was carried out to analyse the Piedmont Fan deposits, fluvial processes, effect of Quaternary tectonics on the morphogenesis of terraces (land units), morphodynamic processes operating on the units, and present land utilisation pattern. Geomorphologically, the area encompasses a multi-staged, fluviogenetic compound land units of five distinct Fan-cut and fill terraces originated due to an intensive interaction of endogenic (related to Himalayan upheaval), masogenic (relared to reactivation of lineaments) and exogenic (surfacial morphodynamic processes including mass wasting) factors during the Quaternary period. Widespread change of Paleo-environmental conditions along with tectonic disposition during the Quaternary period had the major influence on the Piedmont morphogenesis. The area probably underwent at least five phases of tectonic rejuvenation in a cycle of anagenetic revival of this land system.