Mesdc2 plays a key role in cell-surface expression of Lrp4 and postsynaptic specialization in myotubes

Low-density lipoprotein receptor-related protein 4 (Lrp4) is essential for pre- and post-synaptic specialization at the neuromuscular junction (NMJ), an indispensable synapse between a motor nerve and skeletal muscle. Muscle-specific receptor tyrosine kinase MuSK must form a complex with Lrp4 to organize postsynaptic specialization at NMJs. Here, we show that the chaperon Mesdc2 binds to the intracellular form of Lrp4 and promotes its glycosylation and cell-surface expression. Furthermore, knockdown of Mesdc2 suppresses cell-surface expression of Lrp4, activation of MuSK, and postsynaptic specialization in muscle cells. These results suggest that Mesdc2 plays an essential role in NMJ formation by promoting Lrp4 maturation.     

Sexually dimorphic melanin‐based colour polymorphism,feather melanin content,and wing feather structure in the barn owl (Tyto alba)

Feathers confer protection against biophysical agents and determine flying ability. The geometry and arrangement of the barbs, together with the keratin and pigments deposited in the feathers, determine the mechanical stability of the vane, and its stiffness and resistance to abrasive agents. In colour‐polymorphic species, individuals display alternative colour morphs, which can be associated with different foraging strategies. Each morph may therefore require specific flying abilities, and their feathers may be exposed to different abrasive agents. Feathers of differently coloured individuals may thus have a specific structure, and colour pigments may help resist abrasive agents and improve stiffness. We examined these predictions in the barn owl (Tyto alba), a species for which the ventral body side varies from white to dark reddish pheomelanic, and in the number and size of black spots located at the tip of the feathers. White and reddish birds show different foraging strategies, and the size of black feather spots is associated with several phenotypic attributes. We found that birds displaying a darker reddish coloration on the ventral body side deposit more melanin pigments in their remiges, which also have fewer barbs. This suggests that wear resistance increases with darkness, whereas feathers of lighter coloured birds may bend less easily. Accordingly, individuals displaying a lighter reddish coloration on the ventral body side, and those displaying larger black spots, displayed more black transverse bars on their remiges: as larger‐spotted individuals are heavier and longer‐winged birds also have more transverse bars, these bars may reduce feather bending when flying. We conclude that differently coloured individuals produce wing feathers of different strengths to adopt alternative behavioural and life history strategies. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 562–573.     

Biosynthesis of the carbohydrate moieties of arabinogalactan proteins by membrane-bound β-glucuronosyltransferases from radish primary roots

A membrane fraction from etiolated 6-day-old primary radish roots (Raphanus sativus L. var hortensis) contained β-glucuronosyltransferases (GlcATs) involved in the synthesis of the carbohydrate moieties of arabinogalactan proteins (AGPs). The GlcATs transferred [¹⁴C]GlcA from UDP-[¹⁴C]GlcA on to β-(1 → 3)-galactan as an exogenous acceptor substrate, giving a specific activity of 50–150 pmol min^?1 (mg protein)^?1. The enzyme specimen also catalyzed the transfer of [¹⁴C]GlcA on to an enzymatically modified AGP from mature radish root. Analysis of the transfer products revealed that the transfer of [¹⁴C]GlcA occurred preferentially on to consecutive (1 → 3)-linked β-Gal chains as well as single branched β-(1 → 6)-Gal residues through β-(1 → 6) linkages, producing branched acidic side chains. The enzymes also transferred [¹⁴C]GlcA residues on to several oligosaccharides, such as β-(1 → 6)- and β-(1 → 3)-galactotrioses. A trisaccharide, α-l-Araf-(1 → 3)-β-Gal-(1 → 6)-Gal, was a good acceptor, yielding a branched tetrasaccharide, α-l-Araf-(1 → 3)[β-GlcA-(1 → 6)]-β-Gal-(1 → 6)-Gal. We report the first in vitro assay system for β-GlcATs involved in the AG synthesis as a step toward full characterization and cloning.     

Identification of a radical formed in the reaction mixtures of oxidized phosphatidylcholine with ferrous ions using HPLC–ESR and HPLC–ESR–MS

Identification of free radicals was performed for the reaction mixtures of autoxidized 1,2-dilinoleoylphosphatidylcholine (DLPC) with ferrous ions (or DLPC hydroperoxide with ferrous ions) and of DLPC with soybean lipoxygenase using electron spin resonance (ESR), high performance liquid chromatography (HPLC)–ESR and HPLC–ESR–mass spectrometry (MS) combined use of spin trapping technique. ESR measurements of the reaction mixtures showed prominent signals with hyperfine coupling constants (a^N=1.58?mT and a^Hβ=0.26?mT). Outstanding peaks with almost same retention times (autoxidized DLPC, 36.9?min; DLPC hydroperoxide, 35.0?min; DLPC with soybean lipoxygenase, 37.1?min) were observed on the elution profile of the HPLC–ESR analyses of the reaction mixtures. HPLC–ESR–MS analyses of the reaction mixtures gave two ions at m/z 266 and 179, suggesting that 4-POBN/pentyl radical adduct forms in these reaction mixtures.     

Regional Difference of Purinergic Modulation on Adrenergic Neurotransmission in Isolated Rabbit Pulmonary Artery

Abstract

Effects of 2-Chloroadenosine on different parts of pulmonary artery isolated from rabbit were studied, and it was suggested that there was a significant regional difference of purinergic modulation on noradrenaline release between proximal and distal parts of the artery.     

(5Z, 7E)-5,7-Dodecadien-1-ol: Female Sex Pheromone of the Pine Moth Dendrolimus spectabilis Butler

The sex pheromone of the pine moth Dendrolimus spectabilis Butler was tentatively identified as 5,7-dodecadien-l-ol by the use of the electroantennogram technique. Analyses of abdominal tip extracts of virgin females by gas-liquid chromatography and mass spectroscopy showed the presence of a (5Z, 7E)-isomer and a (5E, 7E)-isomer in the ratio of about ca. 5:1. In field examinations with four synthetic isomers of 5,7-dodecadien-l-ol, only traps baited with the (5Z, 7E)-isomer captured an appreciable numbers of male moths.     

A Novel Preparation of a trans-Fused Urea trans-3,4-Ureylenethiophane-1,1-dioxide

A novel synthesis of trans-3,4-ureylenethiophane-1,1-dioxide (X, R=H) from sulfolene via trans-3,4-diaminothiophane-1,1-dioxide (VII, R₁=R₂=H) is described.     

Plasmablasts as Migratory IgG-Producing Cells in the Pathogenesis of Neuromyelitis Optica

Neuromyelitis optica (NMO) is an inflammatory disease characterized by recurrent attacks of optic neuritis and myelitis. It is generally accepted that autoantibodies against aquaporin 4 water channel protein play a pathogenic role in neuromyelitis optica. We have recently reported that plasmablasts are increased in the peripheral blood of this autoimmune disease, and are capable of producing autoantibodies against aquaporin 4. Here, we demonstrate that CD138⁺HLA-DR⁺ plasmablasts, a subset of IgG-producing cells, are increased in the peripheral blood and are enriched among the cerebrospinal fluid (CSF) lymphocytes during the relapse of neuromyelitis optica. Notably, these CD138⁺HLA-DR⁺ plasmablasts overexpress CXCR3, whose ligands are present in the cerebrospinal fluid during the relapse of neuromyelitis optica. These results led us to speculate that plasmablasts producing anti-aquaporin 4 autoantibodies might traffic toward the central nervous system (CNS). Furthermore, we performed single-cell sorting of plasmablasts from peripheral blood and CSF samples from NMO and sequenced the complementarity-determining regions (CDRs) of the IgG heavy chain expressed by the sorted plasmablast clones. There were high frequencies of mutations in the CDRs compared with framework regions, indicating that these plasmablast clones would represent a post-germinal center B-cell lineage. Consistent with the preceding results, the plasmablast clones from the peripheral blood shared the same CDR sequences with the clones from the CSF. These results indicate that IgG-producing plasmablasts, which are guided by helper T-cells, may migrate from the peripheral blood preferentially to the CSF. Since migratory plasmablasts could be involved in the inflammatory pathology of NMO, the B-cell subset and their migration might be an attractive therapeutic target.     

Viability Is Associated with Melanin-Based Coloration in the Barn Swallow (Hirundo rustica)

Pigmentation of body surface in animals can have multiple determinants and accomplish diverse functions. Eumelanin and pheomelanin are the main animal pigments, being responsible of yellow, brownish-red and black hues, and have partly common biosynthetic pathways. Many populations of vertebrates show individual variation in melanism, putatively with large heritable component. Genes responsible for eu- or pheomelanogenesis have pleiotropic but contrasting effects on life-history traits, explaining the patterns of covariation observed between melanization and physiology (e.g. immunity and stress response), sexual behavior and other characters in diverse taxa. Yet, very few studies in the wild have investigated if eu- and pheomelanization predict major fitness traits like viability or fecundity. In this correlative study, by contrasting adult barn swallows (Hirundo rustica) matched for age, sex, breeding site, and year and date of sampling, we show that males but not females that survived until the next year had paler, relatively more eu- than pheomelanic pigmentation of ventral body feathers. Better performance of individuals that allocate relatively more to eumelanogenesis was expected based on previous evidence on covariation between eumelanic pigmentation and specific traits related to immunity and susceptibility to stress. However, together with the evidence of no covariation between viability and melanization among females, this finding raises the question of the mechanisms that maintain variation in genes for melanogenesis. We discuss the possibility that eu- and pheomelanization are under contrasting viability and sexual selection, as suggested by larger breeding and sperm competition success of darker males from other barn swallow subspecies.     

Cell cannibalism and nucleus-fragmented cells in voided urine: useful parameters for cytologic diagnosis of low-grade urothelial carcinoma

OBJECTIVE: To clarify whether the 3 parameters of cell clusters, cell cannibalism and nucleus-fragmented cells could improve diagnostic accuracy for grade 1 urothelial carcinoma (G1UC). STUDY DESIGN: A total of 52 voided urine samples from 31 patients histologically diagnosed as having G1UC were reviewed. In addition, 10 voided urine samples from cases with grade 3 demonstration urothelial carcinoma (G3UC) and 30 voided urine samples from 25 patients with a histologic diagnosis of chronic inflammation of the bladder were evaluated for comparison. Areas of tumor cells with cannibalism were measured. RESULTS: Cell cannibalism was evident in 12 of 31 G1UC cases (38.7%), significantly less often than with G3UC, but never identified in the control group. Mean areas of tumor cells featuring cannibalism were significantly smaller in G1 UC than in G3UC cases. Nucleus-fragmented cells were also less frequent in G1UC than in G3UC, but more common than in the control group. CONCLUSION: Cell cannibalism and nucleus-fragmented cells in voided urine with special attention to areas of tumor cell with cannibalism could be applied as a parameter to improve diagnostic accuracy for G1UC.