Wild relatives of crops are an important source of genetic diversity for agriculture, but their gene repertoire remains largely unexplored. We report the establishment and analysis of a pan-genome of Glycine soja, the wild relative of cultivated soybean Glycine max, by sequencing and de novo assembly of seven phylogenetically and geographically representative accessions. Intergenomic comparisons identified lineage-specific genes and genes with copy number variation or large-effect mutations, some of which show evidence of positive selection and may contribute to variation of agronomic traits such as biotic resistance, seed composition, flowering and maturity time, organ size and final biomass. Approximately 80% of the pan-genome was present in all seven accessions (core), whereas the rest was dispensable and exhibited greater variation than the core genome, perhaps reflecting a role in adaptation to diverse environments. This work will facilitate the harnessing of untapped genetic diversity from wild soybean for enhancement of elite cultivars.

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We prove the global existence of weak solutions to the Cauchy problem for the compressible isentropic Navier-Stokes equations in R n (n = 2, 3) when the Cauchy data are spherically symmetric. The proof is based on the exploitation of the one-dimensional feature of symmetric solutions and use of a new (multidimensional) property induced by the viscous flux. The present paper extends Lions' existence theorem [15] to the case 1 < γ < γ n for spherically symmetric initial data, where γ is the specific heat ratio in the pressure, γ n = 3/2 for n = 2 and γ n = 9/5 for n = 3.

Smooth muscle cells (SMC) exhibit a functional plasticity, modulating from the mature phenotype in which the primary function is contraction, to a less differentiated state with increased capacities for motility, protein synthesis, and proliferation. The present study determined, using Western analysis, double-label immunofluorescence and confocal microscopy, whether changes in phenotypic expression of rabbit aortic SMC in culture could be correlated with alterations in expression and distribution of structural proteins. "Contractile" state SMC (days 1 and 3 of primary culture) showed distinct sorting of proteins into subcellular domains, consistent with the theory that the SMC structural machinery is compartmentalised within the cell. Proteins specialised for contraction (alpha-SM actin, SM-MHC, and calponin) were highly expressed in these cells and concentrated in the upper central region of the cell. Vimentin was confined to the body of the cell, providing support for the contractile apparatus but not co-localising with it. In line with its role in cell attachment and motility, beta-NM actin was localised to the cell periphery and basal cortex. The dense body protein alpha-actinin was concentrated at the cell periphery, possibly stabilising both contractile and motile apparatus. Vinculin-containing focal adhesions were well developed, indicating the cells' strong adhesion to substrate. In "synthetic" state SMC (passages 2-3 of culture), there was decreased expression of contractile and adhesion (vinculin) proteins with a concomitant increase in cytoskeletal proteins (beta-non-muscle [NM] actin and vimentin). These quantitative changes in structural proteins were associated with dramatic changes in their distribution. The distinct compartmentalisation of structural proteins observed in "contractile" state SMC was no longer obvious, with proteins more evenly distributed throughout the cytoplasm to accommodate altered cell function. Thus, SMC phenotypic modulation involves not only quantitative changes in contractile and cytoskeletal proteins, but also reorganisation of these proteins. Since the cytoskeleton acts as a spatial regulator of intracellular signalling, reorganisation of the cytoskeleton may lead to realignment of signalling molecules, which, in turn, may mediate the changes in function associated with SMC phenotypic modulation.

The biliary glycoproteins (BGP or CD66a), a group of different splice variants of a single gene, are members of the carcinoembryonic antigen family and the immunoglobulin super-family. Recently, we detected CD66a on IL-2 activated lymphocytes. In this study we characterized the structure and the expression pattern of BGP on human lymphocytes and investigated its role in T cell activation. Lymphocytes express 2 of the 13 known splice variants , i.e. BGPa and BGPb, which are glycosylated in a lymphocyte-specific manner. Both BGPa and BGPb have the long cytoplasmic tail, which contains two immunoreceptor tyrosine-based inhibitory motif (ITIM)-like motifs, but differ in their extracellular region containing 4 and 3 immunoglobulin-like domains, respectively. On PBL BGP is expressed in small amounts only on B cells and Th cells. Stimulation with IL-2 leads to a strong up-regulation of BGP by these cells, and induces de novo BGP expression on + ˇ T cells, CD8 + and CD56 + cells, but not on CD16 + lymphocytes. This up-regulation of BGP seems to be part of the physiological process of T cell activation, since stimulation with anti-CD3 mAb is sufficient to induce BGP up-regulation. Based on the presence of the two ITIM-like motifs, one may expect that BGP inhibits T cell activation, but surprisingly, engagement of BGP enhances the proliferation of anti-CD3-stimulated T cells.

Pseudomonas aeruginosa possesses a multigene operon that includes phenylalanine hydroxylase (PhhA; phenylalaine 4-monooxygenase, EC 1.14.16.1). phhA encodes PhhA (Mr = 30,288), phhB (Mr = 13,333) encodes a homologue of mammalian 4a-carbinolamine dehydratase/homeodomain protein transregulator, and phhC encodes an aromatic aminotsferase (Mr = 43,237). The reading frames specifying phhB and phhC overlap by 2 bases. The P. aeruginosa PhhA appears to contain iron and is pterin dependent. Unlike the multimeric mammalian hydroxylase, the native P. aeruginosa enzyme is a monomer. The P. aeruginosa PhhA is homologous with mammalian PhhA, tryptophan hydroxylase, and tyrosine hydroxylase. Expression of PhhA from its native promoter required phhB. This may suggest a positive regulatory role for phk8, consistent with the dual catalytic and regulatory roles of the corresponding mammalian homologue.

Rat MSCs cannot be extensively expanded in vitro or be induced to differentiate in an expected cardiomyogenic way by 5-azacytidine-treatment, if the cells are not immortalized.

Amino acid substitutions of hepatitis B surface antigen (HBsAg) may affect the antigenicity and immunogenicity of HBsAg, leading to immune escape and diagnostic failure. The amino acid positions 122 and 160 are known as determinants for HBsAg subtypes d/y and w/r, respectively. The substitution K122I has been shown to strongly affect HBsAg antigenicity. In this study, we investigated the significance of naturally occurring amino acid substitutions K122I, T123N, A159G and K160N. Both T123N and K160N substitutions resulted in additional N-glycosylated forms of HBsAg, while the other mutations produced more glycosylated HBsAg compared with the wild type (wt). Detection of HBsAg by ELISA and immunofluorescence staining indicated that variant HBsAg (vtHBsAg) with K122I was not recognized by HBsAg immunoassays, while vtHBsAg with T123N, A159G, K160N and A159G/K160N had reduced antigenicity. DNA immunization in BALB/c mice revealed that wtHBsAg and vtHBsAg with T123N and K160N are able to induce antibodies to HBsAg (anti-HBs), whereas K122I and A159G greatly impair the ability of HBsAg to trigger anti-HBs responses. The cellular immune response to the HBsAg aa 29-38 epitope was enhanced by the K160N substitution. Using replication competent clones of hepatitis B virus (HBV), T123N and A159G substitutions were shown to strongly reduce virion assembly. The amino acid substitution K160N appeared to compensate for the negative effect of A159G on virion production. These results reveal complex effects of amino acid substitutions on biochemical properties of HBsAg, on antigenicity and immunogenicity, and on the replication of HBV.