A novel allelic variant of the human TSG-6 gene encoding an amino acid difference in the CUB module. Chromosomal localization, frequency analysis, modeling, and expression

Tumor necrosis factor-stimulated gene-6 (TSG-6) encodes a 35-kDa protein, which is comprised of contiguous Link and CUB modules. TSG-6 protein has been detected in the articular joints of osteoarthritis (OA) patients, with little or no constitutive expression in normal adult tissues. It interacts with components of cartilage matrix (e.g. hyaluronan and aggrecan) and thus may be involved in extracellular remodeling during joint disease. In addition, TSG-6 has been found to have anti-inflammatory properties in models of acute and chronic inflammation. Here we have mapped the human TSG-6 gene to 2q23.3, a region of chromosome 2 linked with OA. A single nucleotide polymorphism was identified that involves a non-synonymous G --> A transition at nucleotide 431 of the TSG-6 coding sequence, resulting in an Arg to Gln alteration in the CUB module (at residue 144 in the preprotein). Molecular modeling of the CUB domain indicated that this amino acid change might lead to functional differences. Typing of 400 OA cases and 400 controls revealed that the A(431) variant identified here is the major TSG-6 allele in Caucasians (with over 75% being A(431) homozygotes) but that this polymorphism is not a marker for OA susceptibility in the patients we have studied. Expression of the Arg(144) and Gln(144) allotypes in Drosophila Schneider 2 cells, and functional characterization, showed that there were no significant differences in the ability of these full-length proteins to bind hyaluronan or form a stable complex with inter-alpha-inhibitor.     

Cytoplasmic domain of NCAM140 interacts with ubiquitin-fold modifier-conjugating enzyme-1 (Ufc1)

The neural cell adhesion molecule NCAM is implicated in different neurodevelopmental processes and in synaptic plasticity in adult brain. The cytoplasmic domain of NCAM interacts with several cytoskeletal proteins and signaling molecules. To identify novel interaction partners of the cytosolic domain of NCAM a protein macroarray has been performed. We identified the ubiquitin-fold modifier-conjugating enzyme-1 (Ufc1) as an interaction partner of NCAM140. Ufc1 is one of the enzymes involved in modification of proteins with the ubiquitin-like molecule ubiquitin-fold modifier-1 (Ufm1). We also observed a partial co-localization of NCAM140 with Ufc1 and Ufm1 and increased endocytosis of NCAM140 in the presence of Ufm1 suggesting a possible ufmylation of NCAM140 and a potential novel function of Ufm1 for cell surface proteins.     

Fabrication of Polybenzimidazole/Palladium Nanoparticles Hollow Fiber Membranes for Hydrogen Purification

A novel scheme to fabricate polybenzimidazole (PBI) hollow fiber membranes with a thin skin loaded with fully dispersed palladium nanoparticles is proposed for the first time. Palladium is added to the membrane during the spinning process in the form of ions that coordinate to the imidazole groups of the polymer. This is attractive for membrane production because agglomeration of nanoparticles is minimized and the high‐cost metal is incorporated in only the selective layer—where it is required. Pd‐containing membranes achieve three orders of magnitude higher H₂ permeances and a twofold improvement in H₂/CO₂ selectivity compared to pure PBI hollow fiber membranes.     

Community genetics in the time of next-generation molecular technologies

Understanding the interactions of co-occurring species within and across trophic levels provides key information needed for understanding the ecological and evolutionary processes that underlie biological diversity. As genetics has only recently been integrated into the study of community-level interactions, the time is right for a critical evaluation of potential new, gene-based approaches to studying communities. Next-generation molecular techniques, used in parallel with field-based observations and manipulative experiments across spatio-temporal gradients, are key to expanding our understanding of community-level processes. Here, we introduce a variety of ‘-omics’ tools, with recent studies of plant–insect herbivores and of ectomycorrhizal systems providing detailed examples of how next-generation approaches can revolutionize our understanding of interspecific interactions. We suggest ways that novel technologies may convert community genetics from a field that relies on correlative inference to one that reveals causal mechanisms of genetic co-variation and adaptations within communities.     

Identification of antigen-capturing cells as basophils

Binding of intact Ag is a hallmark of Ag-specific B cells. Apart from B cells, a small number of non-B cells can bind Ag with comparable efficacy as B cells and are found in the peripheral blood, spleen, and bone marrow of mice. This population has been observed for a long time and recently named "Ag-capturing cells." Their identity remained enigmatic. In this study, we show that these cells are basophilic granulocytes. Their ability to capture Ags is dependent on surface IgE receptors and on Ag-specific plasma IgE molecules appearing after immunization. Several surface markers including surface bound IgE, IL-3R, CD45, CD16/32, and the chemokine receptor CCR2 were used to clearly identify these cells. Cross-linkage of surface Igs results in the release of large amounts of IL-4 and IL-6. The data identify basophils as Ag-capturing cells and support the concept of basophils as important regulators of humoral immune responses.     

Ultrastructure of mesoderm in embryos of Opisthopatus roseus (Onychophora, Peripatopsidae): revision of the "long germ band" hypothesis for Opisthopatus

In previous studies, an unusual pattern of development which resembles the "long germ band" development of some insects has been described in the onychophoran Opisthopatus cinctipes. This pattern has been proposed to be a characteristic of the genus Opisthopatus. To test this assumption, the ultrastructure of embryos of O. roseus, the sister species of O. cinctipes, was examined. Two kinds of paired, segmentally arranged coelomic cavities were found in the embryos studied: 1) dorsolateral coelomic cavities lined by extremely thin epithelia, and 2) ventral coelomic cavities situated within the anlagen of ventrolateral body appendages. Only the dorsolateral coelomic cavities can be considered "somites," since they occur earlier during embryogenesis. This is in contrast with the previous view that suggested a ventral position of "somites" in O. cinctipes. In addition, an anterior-to-posterior gradient occurs in the development of O. roseus. Based on our findings, we reevaluated the previous data on O. cinctipes. From this survey, no evidence in support of a "long germ band" hypothesis in Opisthopatus was found. Instead, the embryogenesis in representatives of Opisthopatus is more similar to that in other onychophorans than expected.     

Genome Sequences of Populus tremula Chloroplast and Mitochondrion: Implications for Holistic Poplar Breeding

Complete Populus genome sequences are available for the nucleus (P. trichocarpa; section Tacamahaca) and for chloroplasts (seven species), but not for mitochondria. Here, we provide the complete genome sequences of the chloroplast and the mitochondrion for the clones P. tremula W52 and P. tremula x P. alba 717-1B4 (section Populus). The organization of the chloroplast genomes of both Populus clones is described. A phylogenetic tree constructed from all available complete chloroplast DNA sequences of Populus was not congruent with the assignment of the related species to different Populus sections. In total, 3,024 variable nucleotide positions were identified among all compared Populus chloroplast DNA sequences. The 5-prime part of the LSC from trnH to atpA showed the highest frequency of variations. The variable positions included 163 positions with SNPs allowing for differentiating the two clones with P. tremula chloroplast genomes (W52, 717-1B4) from the other seven Populus individuals. These potential P. tremula-specific SNPs were displayed as a whole-plastome barcode on the P. tremula W52 chloroplast DNA sequence. Three of these SNPs and one InDel in the trnH-psbA linker were successfully validated by Sanger sequencing in an extended set of Populus individuals. The complete mitochondrial genome sequence of P. tremula is the first in the family of Salicaceae. The mitochondrial genomes of the two clones are 783,442 bp (W52) and 783,513 bp (717-1B4) in size, structurally very similar and organized as single circles. DNA sequence regions with high similarity to the W52 chloroplast sequence account for about 2% of the W52 mitochondrial genome. The mean SNP frequency was found to be nearly six fold higher in the chloroplast than in the mitochondrial genome when comparing 717-1B4 with W52. The availability of the genomic information of all three DNA-containing cell organelles will allow a holistic approach in poplar molecular breeding in the future.