Facing loss: coping mechanisms of Mayan widows in Guatemala

In countries of the global south the rights of widows are repeatedly infringed and neglected both by the women’s movement and by the international humanitarian community. Widows in Guatemala suffer especially from lack of official recognition and the psychological consequences of not knowing the fate of their husbands or not being able to bury them or remarry. This article focuses on Mayan Widows in Guatemala and how they cope with the loss in the context of the former military dictatorship and its counterinsurgency campaign against Guatemala’s rural, and mostly Indian citizens, the so-called “la violencia”. The study examines the psychological pain, coping mechanisms of these women and how they fulfil their dual economic roles; their vulnerability to intimidation, violence or abuse; and how this situation redefines their behaviour.Published online: 11 December 2017</p

The Trypanosome Exocyst:A Conserved Structure Revealing a New Role in Endocytosis

Membrane transport is an essential component of pathogenesis for most infectious organisms. In African trypanosomes, transport to and from the plasma membrane is closely coupled to immune evasion and antigenic variation. In mammals and fungi an octameric exocyst complex mediates late steps in exocytosis, but comparative genomics suggested that trypanosomes retain only six canonical subunits, implying mechanistic divergence. We directly determined the composition of the Trypanosoma brucei exocyst by affinity isolation and demonstrate that the parasite complex is nonameric, retaining all eight canonical subunits (albeit highly divergent at the sequence level) plus a novel essential subunit, Exo99. Exo99 and Sec15 knockdowns have remarkably similar phenotypes in terms of viability and impact on morphology and trafficking pathways. Significantly, both Sec15 and Exo99 have a clear function in endocytosis, and global proteomic analysis indicates an important role in maintaining the surface proteome. Taken together these data indicate additional exocyst functions in trypanosomes, which likely include endocytosis, recycling and control of surface composition. Knockdowns in HeLa cells suggest that the role in endocytosis is shared with metazoan cells. We conclude that, whilst the trypanosome exocyst has novel components, overall functionality appears conserved, and suggest that the unique subunit may provide therapeutic opportunities

Syntaxin 16 is a master recruitment factor for cytokinesis

Recently it was shown that both recycling endosome and endosomal sorting complex required for transport (ESCRT) components are required for cytokinesis, in which they are believed to act in a sequential manner to bring about secondary ingression and abscission, respectively. However, it is not clear how either of these complexes is targeted to the midbody and whether their delivery is coordinated. The trafficking of membrane vesicles between different intracellular organelles involves the formation of soluble N-ethylmalei­mide–sensitive factor attachment protein receptor (SNARE) complexes. Although membrane traffic is known to play an important role in cytokinesis, the contribution and identity of intracellular SNAREs to cytokinesis remain unclear. Here we demonstrate that syntaxin 16 is a key regulator of cytokinesis, as it is required for recruitment of both recycling endosome–associated Exocyst and ESCRT machinery during late telophase, and therefore that these two distinct facets of cytokinesis are inextricably linked

Facing loss: coping mechanisms of mayan widows in Guatemala

In countries of the global south the rights of widows are repeatedly infringed and neglected both by the women’s movement and by the international humanitarian community. Widows in Guatemala suffer especially from lack of official recognition and the psychological consequences of not knowing the fate of their husbands or not being able to bury them or remarry. This article focuses on Mayan Widows in Guatemala and how they cope with the loss in the context of the former military dictatorship and its counterinsurgency campaign against Guatemala’s rural, and mostly Indian citizens, the so-called “la violencia”. The study examines the psychological pain, coping mechanisms of these women and how they fulfil their dual economic roles; their vulnerability to intimidation, violence or abuse; and how this situation redefines their behaviour

Biochemische und Zellbiologische Charakterisierung der humanen Proteinkinase X

DFG, 1818/0

DLR SpaceBot Cup 2013: A Space Robotics Competition

In November 2013, the German Aerospace Center (DLR) in Bonn hosted the SpaceBot Cup, Germany’s first of its kind space robotics competition. The scenario is set in a planetary exploration environment with some manipulation tasks. Ten entrants had eight month to define, develop, and build robotic systems and the according ground station setup to conduct a remote testbed mission. Then, the robotic element(s) were deployed onto a sparsely known planetary surface and had to conduct exploration of the environment, find and collect two artificial objects, and mount them to a third object. Communication between ground control station and planetary surface was limited and impaired by delay, making autonomous functionality crucial for the success of the mission. In this report, the motivation, scenario, tasks, and final competition event of the DLR SpaceBot Cup 2013 are presented

Derivation of vascular endothelial cells from human embryonic stem cells under GMP-compliant conditions: towards clinical studies in ischaemic disease

Revascularisation of ischaemic tissue remains an area of substantial unmet clinical need in cardiovascular disease. Strategies to induce therapeutic angiogenesis are therefore attractive. Our recent focus has been on human embryonic stem cell (hESC) strategies since hESC can be maintained in a pluripotent state or differentiated into any desired cell type, including endothelial cells (EC), under defined differentiation culture conditions. We recently published a protocol for non-good manufacturing practice (GMP) feeder- and serum-free hESC-EC-directed monolayer differentiation to vascular EC demonstrating the potential to generate hESC-derived EC in a GMP-compliant manner suitable for use in clinical trials. In this study we modified that laboratory protocol to GMP compliance. EC production was confirmed by flow cytometry, qRT-PCR and production of vascular structures in Matrigel®, yielding approximately 30 % mature VE-cadherin+/PECAM-1+ cells using the GMP-compliant hESC line RC13. In conclusion, we have successfully demonstrated the production of vascular EC under GMP-compliant conditions suitable for clinical evaluation

Phosphorylation of the N-terminus of Syntaxin-16 controls interaction with mVps45 and GLUT4 trafficking in adipocytes

The ability of insulin to stimulate glucose transport in muscle and fat cells is mediated by the regulated delivery of intracellular vesicles containing glucose transporter-4 (GLUT4) to the plasma membrane, a process known to be defective in disease such as Type 2 diabetes. In the absence of insulin, GLUT4 is sequestered in tubules and vesicles within the cytosol, collectively known as the GLUT4 storage compartment. A subset of these vesicles, known as the ‘insulin responsive vesicles’ are selectively delivered to the cell surface in response to insulin. We have previously identified Syntaxin16 (Sx16) and its cognate Sec1/Munc18 protein family member mVps45 as key regulatory proteins involved in the delivery of GLUT4 into insulin responsive vesicles. Here we show that mutation of a key residue within the Sx16 N-terminus involved in mVps45 binding, and the mutation of the Sx16 binding site in mVps45 both perturb GLUT4 sorting, consistent with an important role of the interaction of these two proteins in GLUT4 trafficking. We identify Threonine-7 (T7) as a site of phosphorylation of Sx16 in vitro. Mutation of T7 to D impairs Sx16 binding to mVps45 in vitro and overexpression of T7D significantly impaired insulin-stimulated glucose transport in adipocytes. We show that both AMP-activated protein kinase (AMPK) and its relative SIK2 phosphorylate this site. Our data suggest that Sx16 T7 is a potentially important regulatory site for GLUT4 trafficking in adipocytes