Representation of the identified differentially expressed proteins on a raw 2D-DIGE gel image.

<p>Representation of the identified differentially expressed proteins on a raw 2D-DIGE gel image.</p

Proteomic Alterations in B Lymphocytes of Sensitized Mice in a Model of Chemical-Induced Asthma

<div><p>Introduction and Aim</p><p>The role of B-lymphocytes in chemical-induced asthma is largely unknown. Recent work demonstrated that transferring B lymphocytes from toluene diisocyanate (TDI)-sensitized mice into naïve mice, B cell KO mice and SCID mice, triggered an asthma-like response in these mice after a subsequent TDI-challenge. We applied two-dimensional difference gel electrophoresis (2D-DIGE) to describe the “sensitized signature” of B lymphocytes comparing TDI-sensitized mice with control mice.</p><p>Results</p><p>Sixteen proteins were identified that were significantly up- or down-regulated in B lymphocytes of sensitized mice. Particularly differences in the expression of cyclophilin A, cofilin 1 and zinc finger containing CCHC domain protein 11 could be correlated to the function of B lymphocytes as initiators of T lymphocyte independent asthma-like responses.</p><p>Conclusion</p><p>This study revealed important alterations in the proteome of sensitized B cells in a mouse model of chemical-induced asthma, which will have an important impact on the B cell function.</p></div

Classification of the identified differentially expressed proteins.

<p>The differentially expressed proteins in CD19⁺ B lymphocytes from sensitized versus non-sensitized mice were classified according to biological function (retrieved from Gene Ontology).</p

Differentially expressed proteins in CD19⁺ B cells from TDI-sensitized versus non-sensitized mice (p<0.01).

<p>Proteins are ranked according ontology, followed by most upregulated to most downregulated. Individual mass spectra can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138791#pone.0138791.s001" target="_blank">S1</a> to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138791#pone.0138791.s015" target="_blank">S15</a> Figs.</p><p>* pI and Mw are depicted as theoretical values.</p><p>Differentially expressed proteins in CD19⁺ B cells from TDI-sensitized versus non-sensitized mice (p<0.01).</p

Overview of transcriptionally active <i>S. tropicalis</i> AMP genes, predicted peptides and their molecular weights.

1<p>, by GenBank ESTs.</p>2<p>, by previously reported peptides.</p>3<p>, posttranslational modifications:a, C-terminal amidation; p, pyroglutamate formation; S, tyrosine sulfation.</p>4<p>, predicted but with insignificance scores (<26).</p><p>M.W., molecular weight.</p

Physicochemical properties of <i>S. tropicalis</i> AMPs and HLPs.

1<p>predicted by the PsiPred server (Buchan et al 2010).</p>2<p>at pH = 7.0.</p>3<p>based on the combined consensus scale of Tossi et al. (2002).</p>4<p>expressed as % TFA/AcN solvent at HPLC elution time.</p>5<p>not available.</p

Genomic organization of the <i>Silurana tropicalis</i> AMP gene repertoire.

<p>(A) Gene cluster map showing gene and transcript positions (indicated by numbers 1–15 on the left) and gene orientation (indicated by upward or downward pointing triangles). Genes with incomplete coding sequences are colored grey. Exon organization of each gene/transcript is shown on the right (labeled by the numbers of the gene map), with exon lengths indicated as numbers below bars, untranslated regions colored light blue and coding sequences colored dark-blue. (B) Schematic representation of the <i>S. tropicalis</i> AMP gene cluster and adjacent genes showing preserved synteny with the <i>cck</i> gene in other vertebrates.</p

Precursors encoded by the <i>Silurana tropicalis</i> AMP gene repertoire.

<p>Peptides are predicted based on sequence homology to previously identified peptides (both highlighted in black) and putative cleavage sites (highlighted in gray). Underlined sequences represent predicted signal peptides. Asterisks represent translation stops.</p

Evolutionary diversification of pipid AMP genes.

<p>Phylogenetic relationships of <i>S. tropicalis</i> and <i>X. laevis</i> AMP genes are shown in a consensus tree obtained by Bayesian analyses using the traditional two-step approach of phylogeny inference (separate alignment and Bayesian phylogeny inference) and using direct optimization (integrated Bayesian alignment and phylogeny inference). Each gene is represented here by its precursor protein sequence aligned to visualize similarity with its closely related homologues. Note that several of the <i>X. laevis</i> sequences occupy multiple lines because duplicated exons were aligned to each other. Unlabeled branches in the tree are supported by maximum posterior probabilities (1.00) under both methods; branches that received less support by one or both methods are labeled by their posterior probability under the two-step method (top) and under direct optimization (bottom). Nodes representing gene duplication events are labeled by circles and color-coded as follows: black, the split between <i>cck</i> and the ancestral pipid AMP gene; grey, gene duplication in an ancestor of <i>Silurana</i> and <i>Xenopus</i>; blue, gene duplication in <i>Silurana</i>; and red, gene duplication in <i>Xenopus</i>. Crosses linked by a vertical dashed line mark the divergence of <i>Silurana</i> and <i>Xenopus</i>, the resulting orthologous gene lineages are marked by blue and red branches respectively. Peptides in the precursor proteins are color-coded accordingly.</p

Structural and functional evolution of the pipid defense peptide arsenal.

<p>(A) Evolutionary scenario for the origin and loss of defense peptides and their function along a summarized phylogenetic tree. Numbers along tree branches represent structural changes as mentioned in the legend. (B) Evolutionary trajectory showing structural changes and functional transitions from the ancestral <i>cck</i> gene to the present-day <i>X. laevis xpf-Xl1</i> gene, encoding the AMP XPF and the HLP xenopsin. Only gene duplication events relevant to functional changes (see text) are indicated. (C) Comparative alignment of levitide-like peptides, <i>X. laevis</i> xenopsin and the vertebrate neurohormones with which it shows evolutionary convergence. The origins of the different peptides are indicated on the right. Amino acids are color-coded as follows: white, hydrophobic; grey, near-neutral; purple, uncharged polar; blue, cationic (basic); red; anionic (acidic).</p