Wolfram (DIDMOAD) syndrome is an autosomal recessive neurodegenerative disorder accompanied by insulin-dependent diabetes mellitus and progressive optic atrophy. Recent positional cloning led to identification of the WFS1 (Wolfram syndrome 1) gene, a member of a novel gene family of unknown function. In this study, we generated a specific antibody against the C-terminus of the WFS1 protein and investigated its subcellular localization in cultured cells. We also studied its distribution in the rat brain. Biochemical studies indicated the WFS1 protein to be an integral, endoglycosidase H-sensitive membrane glycoprotein that localizes primarily in the endoplasmic reticulum (ER). Consistent with this, immunofluorescence cell staining of overexpressed WFS1 showed a characteristic reticular pattern over the cytoplasm and overlapped with the ER marker staining. No co-localization of WFS1 with mitochondria argues against an earlier clinical hypothesis that Wolfram syndrome is a mitochondria-mediated disorder. In the rat brain, at both the protein and mRNA level, WFS1 was found to be present predominantly in selected neurons in the hippocampus CA1, amygdaloid areas, olfactory tubercle and superficial layer of the allocortex. These expression sites, i.e. components of the limbic system or structures closely associated with this system, may be involved in the psychiatric, behavioral and emotional abnormalities characteristic of this syndrome. ER localization of WFS1 suggests that this protein plays an as yet undefined role in membrane trafficking, protein processing and/or regulation of ER calcium homeostasis. These studies represent a first step toward the characterization of WFS1 protein, which presumably functions to maintain certain populations of neuronal and endocrine cells.

SummaryCaloric restriction (CR) can delay onset of several age‐related pathophysiologies and extend lifespan in various species, including rodents. CR also induces metabolic remodeling involved in activation of lipid metabolism, enhancement of mitochondrial biogenesis, and reduction of oxidative stress in white adipose tissue (WAT). In studies using genetically modified mice with extended lifespans, WAT characteristics influenced mammalian lifespans. However, molecular mechanisms underlying CR‐associated metabolic remodeling of WAT remain unclear. Sterol regulatory element‐binding protein‐1c (Srebp‐1c), a master transcription factor of fatty acid (FA) biosynthesis, is responsible for the pathogenesis of fatty liver (steatosis). Our study showed that, under CR conditions, Srebp‐1c enhanced mitochondrial biogenesis via increased expression of peroxisome proliferator‐activated receptor gamma coactivator‐1α (Pgc‐1α) and upregulated expression of proteins involved in FA biosynthesis within WAT. However, via Srebp‐1c, most of these CR‐associated metabolic alterations were not observed in other tissues, including the liver. Moreover, our data indicated that Srebp‐1c may be an important factor both for CR‐associated suppression of oxidative stress, through increased synthesis of glutathione in WAT, and for the prolongevity action of CR. Our results strongly suggested that Srebp‐1c, the primary FA biosynthesis‐promoting transcriptional factor implicated in fatty liver disease, is also the food shortage‐responsive factor in WAT. This indicated that Srebp‐1c is a key regulator of metabolic remodeling leading to the beneficial effects of CR.

We have developed a quantitative method for measuring hair growth using optical microscopy and image analysis, and have used this to investigate the rate of growth in subjects with and without alopecia. The hairs were cut from an area 7-8 mm in diameter and 24 h and 72 h later, images of the areas were obtained using an optical microscope and were recorded on a video disc. Measurements of the regrowing hairs, placed parallel to the scalp using a glass slide attached to the front of the microscope, were made using the image analyser. In subjects with little or no baldness there was a clear difference between fast-growing hairs and resting or slow-growing hairs. However, in subjects with alopecia there was no such difference and the growth rate of all the hairs showed a continuous distribution. Using this method other parameters such as the number of hairs per unit area and hair diameter as well as grouping of the hairs could be measured.

Our results suggest that the increase of CB IFN-gamma and IL-4- producing T cells is part of the immune system directed against perinatal intrauterine infections.

Modern single-molecule biophysical experiments require high numerical aperture oil-immersion objectives in close contact with the sample. We introduce two methods of high numerical aperture temperature control which can be implemented on any microscope: objective temperature control using a ring-shaped Peltier device, and stage temperature control using a fluid flow cooling chip in close thermal contact with the sample. We demonstrate the efficacy of each system by showing the change in speed with temperature of two molecular motors, the bacterial flagellar motor and skeletal muscle myosin.