Properties and functions of lactosylceramide from mouse neutrophils.

Lactosylceramide (LacCer), which is essential for many cellular processes, is highly expressed on the plasma membranes of human neutrophils and mediates innate immune functions. Less is known, however, about the properties and biological functions of LacCer in mouse neutrophils. This study therefore analyzed the properties of mouse neutrophil LacCer.

Anti-neutral glycolipid antibodies in encephalomyeloradiculoneuropathy.

Objective: The aim of this study was to review 4 patients with encephalomyeloradiculoneuropathy (EMRN) and assess for autoantibodies against neutral glycolipids.

Methods: We studied the progression of clinical, radiologic, neurophysiologic, and CSF findings, as well as anti-neutral glycolipid antibodies in sera.

Results: All patients developed acute or subacute motor weakness and impaired consciousness.

Membrane microdomains in immunity: glycosphingolipid-enriched domain-mediated innate immune responses.

Over the last 30 years, many studies have indicated that glycosphingolipids (GSLs) expressed on the cell surface may act as binding sites for microorganisms. Based on their physicochemical characteristics, GSLs form membrane microdomains with cholesterol, sphingomyelin, glycosylphosphatidylinositol (GPI)-anchored proteins, and various signaling molecules, and GSL-enriched domains have been shown to be involved in these defense responses. Among the GSLs, lactosylceramide (LacCer, CDw17) can bind to various microorganisms.

The novel neutrophil differentiation marker phosphatidylglucoside mediates neutrophil apoptosis.

A new type of glycolipid, phosphatidylglucoside (PtdGlc), was identified as a component of raft-like membrane domains of the human leukemia cell line HL-60. In this study, we show that PtdGlc forms functional domains that are different from those produced by lactosylceramide (LacCer)-enriched lipid rafts. These rafts initiate neutrophil apoptosis.

Involvement of cholesterol-enriched microdomains in class A scavenger receptor-mediated responses in human macrophages.

Objective: Lipid rafts are cholesterol-enriched microdomains on cell membranes. We hypothesized that these microdomains could involve modified low-density lipoprotein (LDL) uptake.

Methods And Results: Co-localizations of cholesterol-enriched microdomains and CD204 during the uptake of acetyl LDL (AcLDL) and oxidized LDL were observed using Alexa488-labeled polyethylene glycol cholesteryl ester, which is a sensitive probe used to analyze the dynamics of cholesterol-rich lipid microdomains in living cells.

Development of a sphingosylphosphorylcholine detection system using RNA aptamers.

Sphingosylphosphorylcholine (SPC) is a lysosphingolipid that exerts multiple functions, including acting as a spasmogen, as a mitogenic factor for various types of cells, and sometimes as an inflammatory mediator. Currently, liquid chromatography/tandem mass spectrometry (LC/MS/MS) is used for the quantitation of SPC. However, because of the complicated procedures required it may not be cost effective, hampering its regular usage in a routine practical SPC monitoring.

Antibody-specific aptamer-based PCR analysis for sensitive protein detection.

Nucleic acid amplification techniques were applied to the enzyme linked immunosorbent assay (ELISA) with an antibody-specific aptamer, R18. This novel detection system is a modification of the original immuno-polymerase chain reaction (immuno-PCR), but oligonucleotide-labeled antibodies are not required in the assay. This method is performed with the usual ELISA protocol, using an RNA aptamer for rabbit IgG instead of the conventional secondary antibody.

Structural basis for red-shifted emission of a GFP-like protein from the marine copepod Chiridius poppei.

The fluorescence excitation and emission maxima of a GFP-like protein from the marine copepod Chiridius poppei (CpYGFP) show a significant red shift (lambda(ex) = 509 nm, lambda(em) = 517 nm) compared with those of GFP from Aequorea victoria (avGFP) and other GFP-like proteins from marine copepods. We performed crystallographic and biochemical studies to understand why this shift occurs in CpYGFP. The structure of CpYGFP showed that the imidazole side chain of His52 is involved in stacking on the phenol moiety of the chromophore.

RNA aptamers specifically interact with the Fc region of mouse immunoglobulin G.

We have designed the in vitro selection method to obtain some aptamers such as a general antibody-probing agent, which might bind to the constant regions of mouse immunoglobulin G (IgG) subclasses. As a consequence, one of the selected aptamers found to recognize mouse IgG1, 2a, and 3 subclasses. According to the binding assay, it is suggested that this aptamer recognizes the constant regions of mouse IgG subclass.

Two forms of secreted and thermostable luciferases from the marine copepod crustacean, Metridia pacifica.

We cloned two forms of the secreted and thermostable luciferase genes, MpLuc1 and MpLuc2, from the marine copepod, Metridia pacifica. The 840-bp MpLuc1 cDNA comprised a 630-bp open reading frame encoding a 210-amino acid polypeptide (22.7 kDa).

Rabbit antibody detection with RNA aptamers.

Antibody-based detection systems are widely used, but in the cases of immunoprecipitations and enzyme-linked immunoassays, they can be laborious. These techniques require the preparation of at least two kinds of non-cross-reactive immunoglobulin Gs (IgGs), usually made from different species against the single target molecule. Aptamers composed of nucleic acids possess strict recognition ability for the target molecule's three-dimensional structure and, thus, are considered to act like IgG.

Direct observation of histone H2B-YFP fusion proteins and transport of their mRNA between conjugating Paramecia.

Cytoplasmic exchange between conjugating cells of Paramecium caudatum has been implicated by mating experiments using wild-type and behavioral mutant cells. To observe macromolecular transport between mating cells, we cloned and expressed the P. caudatum histone H2B gene as a fusion protein attached to an enhanced yellow fluorescent protein (YFP) named PcVenus.

A novel yellowish-green fluorescent protein from the marine copepod, Chiridius poppei, and its use as a reporter protein in HeLa cells.

A crustacean gene, encoding for a new class of GFP-like protein, has been isolated from a cDNA library of the deep-sea (benthic) copepod crustacean, Chiridius poppei, by expression cloning. The cDNA library was constructed in a pBluescript II vector and screened using a non-UV transilluminator, obtaining a positive clone. The clone consisted of a 781-bp fragment of cDNA with a 660-bp open reading frame, which encoded for a 219-amino acid polypeptide with a calculated molecular mass of 24.

Chromatography of isoforms of recombinant apoaequorin and method for the preparation of aequorin.

Gradient elution chromatography of recombinant apoaequorin carried out in the presence of Ca2+ revealed two isoforms of apoaequorin, reduced and oxidized, whereas in the presence of EDTA 3 isoforms were observed. In a regeneration mixture of apoaequorin, coelenterazine, EDTA, and 2-mercaptoethanol, four isoforms were obtained, of which only one, aequorin, gave light with Ca2+. A method is described for the preparation of highly pure aequorin.

Collection, mapping, and annotation of over 28,000 cDNA clones from japonica rice.

We collected and completely sequenced 28,469 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv.

Structural characterization and artificial fiber formation of Bombyx mori silk fibroin in hexafluoro-iso-propanol solvent system.

High-resolution solution (13)C-NMR and CD studies of Bombyx mori silk fibroin revealed the presence of an ordered secondary structure 3(10)-helix, in hexafluoro-iso-propanol (HFIP). The solid-state structure of the silk fibroin film prepared by drying it gently from the HFIP solution still keep the structure, 3(10)-helix, which was studied with high-resolution solid state (13)C-NMR. The structural transition from the 3(10)-helix to silk II structure, heterogeneous structure including antiparallel beta-sheet, occurred during the artificial spinning from the HFIP solution.

PPARgamma activation and adipocyte differentiation induced by AS-6, a prenyl-phenol antidiabetic antibiotic.

The prenyl-phenol antibiotics ascochlorin-related compounds, are known to reduce serum cholesterol and triglyceride, suppress hypertension, and ameliorate types-I and II diabetes. However, little is known about the molecular mechanism for these physiological effects. Here we report that the ascochlorin derivative, 4-O-carboxymethyl ascochlorin (AS-6) acts as a potent activator of the nuclear hormone receptor, PPARgamma, although it does not activate the related receptors, PPARalpha, PPARdelta or RARalpha.