Long-term ketogenic diet causes hyperlipidemia, liver dysfunction, and glucose intolerance from impaired insulin trafficking and secretion in mice.

A ketogenic diet (KD) is a very low-carbohydrate, very high-fat diet proposed to treat obesity and type 2 diabetes. While KD grows in popularity, its effects on metabolic health are understudied. Here we show that, in male and female mice, while KD protects against weight gain and induces weight loss, over long-term, mice develop hyperlipidemia, hepatic steatosis, and severe glucose intolerance.

AAV-based gene therapy prevents and halts the progression of dilated cardiomyopathy in a mouse model of phosphoglucomutase 1 deficiency (PGM1-CDG).

Phosphoglucomutase 1 (PGM1) deficiency is recognized as the third most common N-linked congenital disorders of glycosylation (CDG) in humans. Affected individuals present with liver, musculoskeletal, endocrine, and coagulation symptoms; however, the most life-threatening complication is the early onset of dilated cardiomyopathy (DCM). Recently, we discovered that oral D-galactose supplementation improved liver disease, endocrine, and coagulation abnormalities, but does not alleviate the fatal cardiomyopathy and the associated myopathy.

Variability in bacterial flagella re-growth patterns after breakage.

Many bacteria swim through liquids or crawl on surfaces by rotating long appendages called flagella. Flagellar filaments are assembled from thousands of subunits that are exported through a narrow secretion channel and polymerize beneath a capping scaffold at the tip of the growing filament. The assembly of a flagellum uses a significant proportion of the biosynthetic capacities of the cell with each filament constituting ~1% of the total cell protein.

ASC contributes to metastasis of oral cavity squamous cell carcinoma.

ASC (Apoptosis-associated Speck-like protein containing a CARD) acts as a platform protein in the inflammasome cascade of some cancer types. However, its potential involvement in OSCC (oral cavity squamous cell carcinoma) has not yet been determined. Here, we investigated the potential role of ASC in OSCC.

Ciliopathy proteins establish a bipartite signaling compartment in a C. elegans thermosensory neuron.

How signaling domains form is an important, yet largely unexplored question. Here, we show that ciliary proteins help establish two contiguous, yet distinct cyclic GMP (cGMP) signaling compartments in Caenorhabditis elegans thermosensory AFD neurons. One compartment, a bona fide cilium, is delineated by proteins associated with Bardet-Biedl syndrome (BBS), Meckel syndrome and nephronophthisis at its base, and requires NPHP-2 (known as inversin in mammals) to anchor a cGMP-gated ion channel within the proximal ciliary region.

The microtubule-associated protein EB1 links AIM2 inflammasomes with autophagy-dependent secretion.

Inflammasomes are multi-protein complexes that regulate chronic inflammation-associated diseases by inducing interleukin-1 β (IL-1β) secretion. Numerous components involved in inflammasome activation have been identified, but the mechanisms of inflammasome-mediated IL-1β secretion have not yet been fully explored. Here, we demonstrate that end-binding protein 1 (EB1), which is required for activation of AIM2 inflammasome complex, links the AIM2 inflammasome to autophagy-dependent secretion.

Endophilin B is required for the Drosophila oocyte to endocytose yolk downstream of Oskar.

The nutritional environment is crucial for Drosophila oogenesis in terms of controlling hormonal conditions that regulate yolk production and the progress of vitellogenesis. Here, we discovered that Drosophila Endophilin B (D-EndoB), a member of the endophilin family, is required for yolk endocytosis as it regulates membrane dynamics in developing egg chambers. Loss of D-EndoB leads to yolk content reduction, similar to that seen in yolkless mutants, and also causes poor fecundity.

The gradient of Gurken, a long-range morphogen, is directly regulated by Cbl-mediated endocytosis.

The asymmetric localization of gurken mRNA and post-translational sorting mechanisms are responsible for the polar distribution of Gurken protein in Drosophila. However, endocytosis of Egfr, the receptor for Gurken in the follicle cells, also plays a role in shaping the extracellular gradient of the Gurken morphogen. Previously, we have found that mutation in the Cbl gene caused elevated Egfr signaling along the dorsoventral axis, and resulted in dorsalization phenotypes in embryos and egg shells.

Regulation of endocytic recycling by C. elegans Rab35 and its regulator RME-4, a coated-pit protein.

Using Caenorhabditis elegans genetic screens, we identified receptor-mediated endocytosis (RME)-4 and RME-5/RAB-35 as important regulators of yolk endocytosis in vivo. In rme-4 and rab-35 mutants, yolk receptors do not accumulate on the plasma membrane as would be expected in an internalization mutant, rather the receptors are lost from cortical endosomes and accumulate in dispersed small vesicles, suggesting a defect in receptor recycling. Consistent with this, genetic tests indicate the RME-4 and RAB-35 function downstream of clathrin, upstream of RAB-7, and act synergistically with recycling regulators RAB-11 and RME-1.

Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes.

Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.

Morphogenesis of the hepatitis B virion and subviral particles in the liver of transgenic mice.

Up to date, no ultrastructure showing the HBV budding site has ever been reported. In this study, the liver of transgenic mice expressing a high titer of HBV was processed for cryo-ultrathin section electron microscopy. This approach preserves membrane structures very well and thus allowed us to find HBV (Dane particles) and subviral particles (spherical and filamentous form) present separately inside the lumen of the endoplasmic reticulum (ER).

Thermally-induced order-order transition of DNA-cationic surfactant complexes.

Polyanionic DNA interacts with cationic amphiphiles to form electrostatic complexes exhibiting rich self-assembled structures. This type of complex has been considered as a nonviral carrier in gene therapy and as a template for nanostructure construction. Here we report a thermally-induced phase transition of the complexes of DNA with the mixtures of a cationic surfactant, dodecyltrimethyl bromide (DTAB), and a neutral lipid, dioleoylphosphatidylethanolamine (DOPE), in fully hydrated state.

Restriction of vaccinia virus replication by a ced-3 and ced-4-dependent pathway in Caenorhabditis elegans.

Genetic tractability and easy manipulation make Caenorhabditis elegans a good model to study host-pathogen interactions. Dozens of different bacterial species can pathogenically infect C. elegans under laboratory conditions, and all of these microbes are extracellular pathogens to nematodes.

Mesomorphic complexes of DNA with the mixtures of a cationic surfactant and a neutral lipid.

Polyanionic DNA binds to cationic lipids to form electrostatic complexes exhibiting rich self-assembled structures. These types of complexes have been considered as a nonviral carrier in gene therapy and as a template for nanostructure construction. For the latter application where biocompatibility is not the key issue, replacement of cationic lipid by cationic surfactant is advantageous due to the wide availability of surfactant.

Caenorhabditis elegans RME-6 is a novel regulator of RAB-5 at the clathrin-coated pit.

Here we identify a new regulator of endocytosis called RME-6. RME-6 is evolutionarily conserved among metazoans and contains Ras-GAP (GTPase-activating protein)-like and Vps9 domains. Consistent with the known catalytic function of Vps9 domains in Rab5 GDP/GTP exchange, we found that RME-6 binds specifically to Caenorhabditis elegans RAB-5 in the GDP-bound conformation, and rme-6 mutants have phenotypes that indicate low RAB-5 activity.

DNA-induced aggregation of zwitterionic oligolamellar liposome.

Liposome consisting of a single zwitterionic lipid as the potential vector for gene therapy has been reported recently; however, whether polyanionic DNA can bind directly with zwitterionic lipid without the aid of multivalent salt still remains unresolved. In this study, we reveal the aggregation of zwitterionic oligolamellar liposomes composed of 1,2-di(cis-9-octadecenoyl)-sn-glycero-3-phosphocholine induced by DNA without the presence of multivalent salt. Our results demonstrate that only a small fraction (<10%) of DNA can bind electrostatically with a portion of the liposomes.

A two-state model for the multilamellar structure of a DNA/cationic lipid complex in the bulk.

Polyanionic DNA can bind electrostatically with cationic lipids to form a complex used for gene delivery and nanostructure construction. Here, we reveal two multilamellar phases, L(I) and L(II), characterized by distinct states of lipid packing and DNA conformation in a DNA/cationic lipid complex in the bulk state. The L(II) phase, formed when the lipids are in excess of DNA in terms of overall ionic charge, is composed of B-DNA confined between the bilayers with the lipid tails aligning normal to the lamellar interface.