The mother of all endocytosis

Massive endocytosis is initiated by a series of steps that involve a sudden influx of calcium ions, changes in mitochondria, and modification of surface proteins by lipids. A better understanding of this process could lead to new approaches to reducing the tissue damage that is caused by heart attacks

Sperm BerserKers

Human sperm cells rely on an unusual type of potassium ion channel

Housing Policies in Latin America: overview of the four largest economies

The aim of this paper is to examine the differences and similarities in housing policies in the four Latin American countries of Argentina, Brazil, Chile and Colombia. The article uses the welfare regime approach, modified by a recognition of path dependence, to identify a number of phases that each country has passed through. However, attention is drawn to the substantial differences in the circumstances in each country and the extent and duration of the different phases. It is concluded that it can be beneficial to use the concept of a Latin American housing regime, but that this general picture has to be used with an understanding of the path dependence caused by the different context in the individual countries

The concept of subjective well-being in housing research

The aim of this article is to review the ways in which subjective well-being has been conceptualized within housing research, with a view to evaluating the use of the concept, the insights it has generated, the problems that have been experienced and the possible range of lessons that might be taken forward. The article begins with an analysis of the reasons why subjective well-being has become popular as a conceptual tool in many fields. The article continues with a discussion of the range of definitions that appear in the literature which leads into discussions of the research techniques and methodologies that have been used in empirical research. Empirical studies which focussed on the impact of physical housing conditions and tenure on subjective well-being are reviewed in order to evaluate what is known about the impact of housing on both personal and collective subjective well-being. This review highlights issues of status, reference groups and adaptation that are important insights from the subjective well-being approach that should set the agenda for further research in this area. The conclusion is that the relationship between housing and subjective well-being is a complex one that repays further study in order to understand the rich texture of the role of housing in people’s lives. The article concludes with suggestions for both conceptual and methodological approaches and the focus of future research

Anion-Sensitive Fluorophore Identifies the Drosophila Swell-Activated Chloride Channel in a Genome-Wide RNA Interference Screen

When cells swell in hypo-osmotic solutions, chloride-selective ion channels ($Cl_{swell}$) activate to reduce intracellular osmolality and prevent catastrophic cell rupture. Despite intensive efforts to assign a molecular identity to the mammalian $Cl_{swell}$ channel, it remains unknown. In an unbiased genome-wide RNA interference (RNAi) screen of Drosophila cells stably expressing an anion-sensitive fluorescent indicator, we identify Bestrophin 1 (dBest1) as the Drosophila $Cl_{swell}$ channel. Of the 23 screen hits with mammalian homologs and predicted transmembrane domains, only RNAi specifically targeting dBest1 eliminated the $Cl_{swell}$ current ($I_{Clswell}$). We further demonstrate the essential contribution of dBest1 to Drosophila $I_{Clswell}$ with the introduction of a human Bestrophin disease-associated mutation (W94C). Overexpression of the W94C construct in Drosophila cells significantly reduced the endogenous $I_{Clswell}$. We confirm that exogenous expression of dBest1 alone in human embryonic kidney (HEK293) cells creates a clearly identifiable Drosophila–like $I_{Clswell}$. In contrast, activation of mouse Bestrophin 2 (mBest2), the closest mammalian ortholog of dBest1, is swell-insensitive. The first 64 residues of dBest1 conferred swell activation to mBest2. The chimera, however, maintains mBest2-like pore properties, strongly indicating that the Bestrophin protein forms the $Cl_{swell}$ channel itself rather than functioning as an essential auxiliary subunit. dBest1 is an anion channel clearly responsive to swell; this activation depends upon its N-terminus

Development of a genetic transformation method for seabuckthorn (Hippophae rhamnoides L.)

Seabuckthorn (Hippophae rhamnoides L.) is a dioecious plant with berries containing highamounts of several bioactive compounds with nutritional and medicinal traits. It is also planted tocontrol soil erosion. A genetic transformation procedure will facilitate studies of the control ofplant development and interactions with symbionts and pathogens, and will provide a tool forplant breeding. Here, we present a particle bombardment method for transforming seabuckthorn.The early stages of induced adventitious shoots from roots were chosen as a novel target tissue forthe transformation procedure. The root system was bombarded with gold particles coated withplasmid pRT99gus containing genes for plant kanamycin resistance and for β-glucuronidase expression,and shoots were regenerated under kanamycin selection. PCR analysis of the regeneratedtransformed lines confirmed the presence of a 603 bp gus (uidA) gene fragment and a 1.5 kbfragment from the 35S promoter in three shoots from independent transformation events

Controlled delivery of bioactive molecules into live cells using the bacterial mechanosensitive channel MscL

Bacterial mechanosensitive channels are some of the largest pores in nature. In particular, MscL, with a pore diameter > 25 Å, allows passage of large organic ions and small proteins. Functional MscL reconstitution into lipids has been proposed for applications in vesicular-based drug release. Here we show that these channels can be functionally expressed in mammalian cells to afford rapid controlled uptake of membrane impermeable molecules. We first demonstrate that MscL gating in response to increased membrane tension is preserved in mammalian cell membranes. Molecular delivery is controlled by adopting an established method of MscL charge-induced activation. We then determine pore size limitations using fluorescently labeled model cargoes. Finally, we activate MscL to introduce the cell-impermeable bi-cyclic peptide phalloidin, a specific marker for actin filaments, into cells. We propose that MscL will be a useful tool for gated and controlled delivery of bioactive molecules into cells