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The family of dynamin proteins is known to function in many eukaryotic membrane fusion and fission events. The yeast dynamin-related protein Vps1 functions at several stages of membrane trafficking, including Golgi apparatus to endosome and vacuole, peroxisomal fission, and endocytic scission. We have previously shown that in its endocytic role, Vps1 functions with the amphiphysin heterodimer Rvs161/Rvs167 to facilitate scission and release of vesicles. Phosphoproteome studies of Saccharomyces cerevisiae have identified a phosphorylation site in Vps1 at serine 599. In this study, we confirmed this phosphorylation event, and we reveal that, like Rvs167, Vps1 can be phosphorylated by the yeast cyclin-associated kinase Pho85 in vivo and in vitro. The importance of this posttranslational modification was revealed when mutagenesis of S599 to a phosphomimetic or nonphosphorylatable form caused defects in endocytosis but not in other functions associated with Vps1. Mutation to nonphosphorylatable valine inhibited the Rvs167 interaction, while both S599V and S599D caused defects in vesicle scission, as shown by both live-cell imaging and electron microscopy of endocytic invaginations. Our data support a model in which phosphorylation and dephosphorylation of Vps1 promote distinct interactions and highlight the importance of such regulatory events in facilitating sequential progression of the endocytic process. [ABSTRACT FROM AUTHOR]

This article explores the work of three contemporary Northern Irish poets, Leontia Flynn, Sinéad Morrissey and Alan Gillis, asking how this work relates to fragility as experienced in Northern Ireland. Is there, within this poetry, a fostering of hope with respect to Northern Ireland's fragile future? Does a new generation of poets look for continuity with the past or does it strike out on a new path? The first part of the article provides a brief introduction to the ‘first-generation peace poets’, and also gives an overview of the ways in which Northern Irish poetry has been criticized in recent decades. It then suggests that this literature might be read through the lens of the elegiac tradition, as well as by exploring the ‘post-theory’ approach of new aestheticism. The second part comprises a series of close readings, with particular emphasis on poems about Belfast, and other poems that deal with themes of loss. [ABSTRACT FROM PUBLISHER]

This article offers information on the Mutual Legal Assistance (MLA) Unit of the Serious Fraud Office (SFO) of Great Britain. The MLA unit was created through the amendment of the Criminal Justice Act 1987 by the Criminal Justice and Public Order Act 1994. Since 1995 requests for assistance referred by the British Central Authority from Commonwealth countries to the SFO have increased in number, particularly from African countries.

Vps1 is the yeast dynamin-like protein that functions during several membrane trafficking events including traffic from Golgi to vacuole, endosomal recycling and endocytosis. Vps1 can also function in peroxisomal fission indicating that its ability to drive membrane fission is relatively promiscuous. It has been of interest therefore that several mutations have been identified in Vps1 that only disrupt its endocytic function. Most recently, disruption of the interaction with actin through mutation of residues in one of the central stalk α helices (RR457,458 EE) has been shown to disrupt endocytosis and cause an accumulation of highly elongated invaginations in cells. This data supports the idea that an interaction between Vps1 and actin is important to drive the scission stage in endocytosis. Another Vps1 mutant generated in the study was vps1 E461K. Here we show data demonstrating that the E461K mutation also disrupts endocytosis but at an early stage, resulting in inhibition of the invagination step itself. [ABSTRACT FROM PUBLISHER]