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MANY A WORLD War I historian has tried to explain why Africans in the German colonies, Askari soldiers as well as bearers, exhibited such a high level of loyalty throughout [...]

Re. 'Rush to Disaster,' by Ron Soodalter, July 2014: The article once again reminds us that ill-equipped parade-ground soldiers will be killed when attacked by a large element of brutally [...]

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The fear of a gas attack (Portfolio, May 2010) was universal for the warring European states--vestiges of World War I. The Nazis issued gas masks, Volksgasmasken ('people's gas masks') to [...]

[Re. 'What We Learned from the Dieppe Raid,' by Nigel Jones, January:] What we learned is that poor planning and lousy intelligence leads to disaster. But I thought we had [...]

Williamson Murray's article 'The Making of Hitler's Army' (Nov/Dec) appears to make the Wehrmacht responsible for Adolf Hitler's rise to power. Let's get the facts straight: Hitler was Germany's national [...]

Richard A. Gabriel's 'The Right Hand of Khan' [May/June] brought back fond memories. I grew up 10 miles or so south of Wahlstatt and vividly remember the 1727 baroque abbey [...]

Several letters to the editor are presented in response to the articles in previous issues including "The Myths of Blitzkrieg and the 1940 Campaign," in the March 2006 issue, "Traditional and Irregular War," in the March 2006 issues, and "Lights Off at the Pentagon," in the February 2006 issue.

Hrs-2, via interactions with SNAP-25, plays a regulatory role on the exocytic machinery. We now show that Hrs-2 physically interacts with Eps15, a protein required for receptor-mediated endocytosis. The Hrs-2/Eps15 interaction is calcium dependent, inhibited by SNAP-25 and alpha-adaptin, and results in the inhibition of receptor-mediated endocytosis. Immunoelectron microscopy reveals Hrs-2 localization on the limiting membrane of multivesicular bodies, organelles in the endosomal pathway. These data show that Hrs-2 regulates endocytosis, delineate a biochemical pathway (Hrs-2-Eps15-AP2) in which Hrs-2 functions, and suggest that Hrs-2 acts to provide communication between endo- and exocytic processes.

Molecular mechanisms of vesicle transport between the prevacuolar compartment and the vacuole in yeast or the lysosome in mammalian cells are poorly understood. To learn more about the specificity of this intercompartmental step, we have examined the subcellular localization of a SEC1 homologue, Vps33p, a protein implicated to function in transport between the prevacuolar compartment and the vacuole. Following short pulses, 80-90% of newly synthesized Vps33p cofractionated with a cytosolic enzyme marker after making permeabilized yeast cells. However, during a chase, 20-40% of Vps33p fractionated with permeabilized cell membranes in a time-dependent fashion with a half-time of approximately 40 min. Depletion of cellular ATP increased the association rate to a half-time of approximately 4 min and caused 80-90% of newly synthesized Vps33p to be associated with permeabilized cell membranes. The association of Vps33p with permeabilized cell membranes was reversible after restoring cells with glucose before permeabilization. The N-ethylmaleimide-sensitive fusion protein homologue, Sec18p, a protein with known ATP binding and hydrolysis activity, displayed the same reversible energy-dependent sedimentation characteristics as Vps33p. We determined that the photosensitive analog, 8-azido-[alpha-32P]ATP, could bind directly to Vps33p with low affinity. Interestingly, excess unlabeled ATP could enhance photoaffinity labeling of 8-azido-[alpha-32P]ATP to Vps33p, suggesting cooperative binding, which was not observed with excess GTP. Importantly, we did not detect significant photolabeling after deleting amino acid regions in Vps33p that show similarity to ATP interaction motifs. We visualized these events in living yeast cells after fusing the jellyfish green fluorescent protein (GFP) to the C terminus of full-length Vps33p. In metabolically active cells, the fully functional Vps33p-GFP fusion protein appeared to stain throughout the cytoplasm with one or two very bright fluorescent spots near the vacuole. After depleting cellular ATP, Vps33p-GFP appeared to localize with a punctate morphology, which was also reversible upon restoring cells with glucose. Overall, these data support a model where Vps33p cycles between soluble and particulate forms in an ATP-dependent manner, which may facilitate the specificity of transport vesicle docking or targeting to the yeast lysosome/vacuole.

Several letters to the editor are presented in response to articles in previous issues including the "Journal of a Platoon Leader in Afghanistan," in the December 2010 issue, "The Danger of Extrapolating From Today's Wars," by Richard Hart Sinnreich in the December 2010 issue and "Harsh Lessons From Task Force Smith," by Eric C. Ludvigsen in the November 2010 issue.