Escherichia coli GlpG is an integral membrane protein that belongs to the widespread rhomboid protease family. Rhomboid proteases, like site-2 protease (S2P) and gamma-secretase, are unique in that they cleave the transmembrane domain of other membrane proteins. Here we describe the 2.1 A resolution crystal structure of the GlpG core domain. This structure contains six transmembrane segments. Residues previously shown to be involved in catalysis, including a Ser-His dyad, and several water molecules are found at the protein interior at a depth below the membrane surface. This putative active site is accessible by substrate through a large 'V-shaped' opening that faces laterally towards the lipid, but is blocked by a half-submerged loop structure. These observations indicate that, in intramembrane proteolysis, the scission of peptide bonds takes place within the hydrophobic environment of the membrane bilayer. The crystal structure also suggests a gating mechanism for GlpG that controls substrate access to its hydrophilic active site.

By a simple method, that is, by heating raw materials in a flowing gas at ambient pressure, Si 3 N 4 , Ga 2 O 3 , and ZnO nanowires, SiC nanocables, and SiO 2 amorphous nanowires are synthesized without metal catalysts. The diameters of these one-dimensional nanoscale materials are greatly affected by synthesis temperatures. At suitable synthesis temperatures, their diameters are <100 nm. The growth mechanisms of these nanowires are discussed preliminarily.

Crystalline boron nanowires with tetragonal structure have been synthesized based on laser ablation of a B/NiCo target; the nanowires are sometimes single crystals and have a droplet at one end of the nanowire; the droplet contains B, Ni and Co elements, which indicates that the vapor-liquid-solid (VLS) mechanism may play a key role in the growth of the boron nanowires.

Aluminum nitride nanowires have been synthesized in bulk from carbon nanotubes (CNTs) at relatively low temperatures. This method produces AlN nanowires through the reaction of the carbon nanotubes, Al, and Al2O3 in a flowing NH3 atmosphere. The diameters of the products, mainly in the range of 10−50 nm, correspond with the diameters of the carbon nanotubes, which provides a promising way to control the diameters of the AlN nanowires. The AlN nanowires fabricated in this way are single crystals covered by a thin amorphous layer. The small diameter and single crystal form make the AlN nanowires highly flexible. The growth mechanism of the AlN nanowires and the factors that allow a decrease in the synthesis temperature are discussed.

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Aligned and diameter‐controlled one‐dimensional nickel–carbon nanotubes and Ag–Si heterojunctions (see Figure) have been synthesized by a novel combination of electrochemical deposition and chemical vapor deposition with anodic aluminum oxide templates. No external catalysts are introduced in the chemical reactions. In the joint regions of the heterojunctions, no amorphous layers are found. These heterojunctions are significant for the development of electronics.

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The small p97/VCP-interacting protein (SVIP) functions as an inhibitor of the endoplasmic reticulum (ER)-associated degradation (ERAD) pathway. Here we show that overexpression of SVIP in HeLa cells leads to localization of p97/VCP at the plasma membrane, intracellular foci and juxtanuclear vacuoles. The p97/VCP-positive vacuolar structures colocalized or associated with LC3 and lamp1, suggesting that SVIP may regulate autophagy. In support of this possibility, knockdown of SVIP diminished, whereas overexpression of SVIP enhanced LC3 lipidation. Surprisingly, knockdown of SVIP reduced the levels of p62 protein at least partially through downregulation of its mRNA, which was accompanied by a decrease in starvation-induced formation of p62 bodies. Overexpression of SVIP, on the other hand, increased the levels of p62 protein and enhanced starvation-activated autophagy as well as promoted sequestration of polyubiquitinated proteins and p62 in autophagosomes. These results suggest that SVIP plays a regulatory role in p97 subcellular localization and is a novel regulator of autophagy.