Genetic Relationships Within and Between Capsicum Species

Genetic relationships were estimated among 24 accessions belonging to 11 species of Capsicum, using 2,760 RAPD markers based on touch-down polymerase chain reactions (Td-RAPD-PCR). These markers were implemented in analyses of principal coordinates, unweighted pair group mean average, and 2,000 bootstrap replications. The accessions were divided into four groups, corresponding to previously described Capsicum complexes: C. annuum complex (C_A), C. baccatum complex (C_B), C. pubescens complex (C_P), and C. chacoense accessions (C_A/_B). Their overall mean genetic similarity index was 0.487 ± 0.082, ranging from 0.88 to 0.32, based on Jaccard’s coefficient. The highest genetic variation was observed among the accessions in C_P; the accessions in C_B had a low level of variation as judged from the standard deviations of the genetic similarity indices. Based on the Td-RAPD-PCR markers, the 24 accessions were divided into four major groups, three of which corresponded to the three distinct Capsicum complexes. Accessions of C. chacoense were found to be equally related to complexes C_A, C_B, and C_P.     

Differential expression patterns of genes containing microsatellites in Capsicum annuum L.

Microsatellites are important for research in both basic and applied sciences. Understanding how genes containing microsatellites are expressed and regulated in different tissues and developmental stages is a fundamental and challenging question. However, there has been limited study of differential expression of genes containing microsatellites in different plant tissues and developmental stages. We studied microsatellite-containing gene expression profiles in 16 different tissues and at different developmental stages in pepper (Capsicum annuum L.). Results indicated that tissue-specific genes contained more dinucleotide microsatellites, and housekeeping genes contained more trinucleotide microsatellites. Differential expression patterns of microsatellite-containing genes indicated that, in the longer term, development of allele-specific markers for genes controlling agronomic traits will be useful for advancing the science of plant breeding. This is the first report on differential expression of microsatellite-containing genes within tissues and developmental stages in pepper.     

Evolution of the CD163 family and its relationship to the bovine gamma delta T cell co-receptor WC1

Background  

The scavenger receptor cysteine rich (SRCR) domain is an ancient and conserved protein domain. CD163 and WC1 molecules are classed together as group B SRCR superfamily members, along with Spα, CD5 and CD6, all of which are expressed by immune system cells. There are three known types of CD163 molecules in mammals, CD163A (M130, coded for by CD163), CD163b (M160, coded for by CD163L1) and CD163c-α (CD163L1 or SCART), while their nearest relative, WC1, is encoded by a multigene family so far identified in the artiodactyl species of cattle, sheep, and pigs.     

Heligmosomoides polygyrus induces TLR4 on murine mucosal T cells that produce TGFbeta after lipopolysaccharide stimulation

Helminths are immune modulators that down-regulate colitis in inflammatory bowel disease. In animal models, intestinal bacteria drive colitis and in humans certain alleles of the LPS receptor protein TLR4 increase inflammatory bowel disease susceptibility. To understand helminthic immune modulation in the gut, we studied the influence of intestinal Heligmosomoides polygyrus colonization on LPS-induced lamina propria mononuclear cell (LPMC) cytokine responses in mice. LPS did not stimulate TGFbeta production from LPMC of uninfected mice. LPS strongly induced LPMC from worm-infected animals to secrete TGFbeta, but not TNF-alpha or IL-12. The TGFbeta derived from mucosal T cells. Helminth infection up-regulated TLR4 expression only in lamina propria T cells. LPMC from worm-infected TLR4 mutant animals did not respond to LPS, suggesting that LPS required TLR4 to stimulate TGFbeta secretion. Thus, during helminth infection, LPS challenge induces mucosal T cells to make TGFbeta through a TLR4-dependent process without promoting synthesis of proinflammatory cytokines.     

Decreased alveolar macrophage apoptosis is associated with increased pulmonary inflammation in a murine model of pneumococcal pneumonia

Regulation of the inflammatory infiltrate is critical to the successful outcome of pneumonia. Alveolar macrophage apoptosis is a feature of pneumococcal infection and aids disease resolution. The host benefits of macrophage apoptosis during the innate response to bacterial infection are incompletely defined. Because NO is required for optimal macrophage apoptosis during pneumococcal infection, we have explored the role of macrophage apoptosis in regulating inflammatory responses during pneumococcal pneumonia, using inducible NO synthase (iNOS)-deficient mice. iNOS(-/-) mice demonstrated decreased numbers of apoptotic macrophages as compared with wild-type C57BL/6 mice following pneumococcal challenge, greater recruitment of neutrophils to the lung and enhanced expression of TNF-alpha. Pharmacologic inhibition of iNOS produced similar results. Greater pulmonary inflammation was associated with greater levels of early bacteremia, IL-6 production, lung inflammation, and mortality within the first 48 h in iNOS(-/-) mice. Labeled apoptotic alveolar macrophages were phagocytosed by resident macrophages in the lung and intratracheal instillation of exogenous apoptotic macrophages decreased neutrophil recruitment in iNOS(-/-) mice and decreased TNF-alpha mRNA in lungs and protein in bronchial alveolar lavage, as well as chemokines and cytokines including IL-6. These changes were associated with a lower probability of mice becoming bacteremic. This demonstrates the potential of apoptotic macrophages to down-regulate the inflammatory response and for the first time in vivo demonstrates that clearance of apoptotic macrophages decreases neutrophil recruitment and invasive bacterial disease during pneumonia.     

Polymorphic Microsatellite Markers Transferable Across <Emphasis Type="Italic">Capsicum</Emphasis> Species

Pepper (Capsicum annuum L.) is one of the most important crops in the family Solanaceae. However, the number of polymorphic molecular loci detected in this important crop is far behind that of other cultivated plant species. In the present study, a total of 45 microsatellite primer pairs were developed using Capsicum expressed sequence tags databases. Microsatellite primer pairs were tested using several species of Capsicum and several genera in the family Solanaceae including tomato, potato, eggplant, and tobacco. Results indicated that microsatellite primer pairs amplified genomic targets of C. annuum L., Capsicum baccatum L., Capsicum chacoense L., Capsicum chinense L., Capsicum frutescens L., and Capsicum pubescens Ruiz et Pavon, indicating species transferability within Capsicum. Further analyses revealed that amplicons of these primer pairs segregated 1:2:1 or 3:1 Mendelian fashions in 38 F₂ individuals of pepper. It was also noted that markers derived from sequences containing dinucleotide repeats were generally more polymorphic at the intraspecific level than sequences containing trinucleotide repeats. All the microsatellite primer pairs developed in this study will be useful for marker-assisted selection and mapping studies in pepper.     

Boron,a Trace Mineral,Alleviates Gentamicin-Induced Nephrotoxicity in Rats

Biological Trace Element Research - The present study was considered to assess the protective effects of boron (B) on gentamicin-induced oxidative stress, proinflammatory cytokines, and...     

The salivary secretome of the tsetse fly Glossina pallidipes (Diptera: Glossinidae) infected by salivary gland hypertrophy virus

Background

The competence of the tsetse fly Glossina pallidipes (Diptera; Glossinidae) to acquire salivary gland hypertrophy virus (SGHV), to support virus replication and successfully transmit the virus depends on complex interactions between Glossina and SGHV macromolecules. Critical requisites to SGHV transmission are its replication and secretion of mature virions into the fly''s salivary gland (SG) lumen. However, secretion of host proteins is of equal importance for successful transmission and requires cataloging of G. pallidipes secretome proteins from hypertrophied and non-hypertrophied SGs.

Methodology/Principal Findings

After electrophoretic profiling and in-gel trypsin digestion, saliva proteins were analyzed by nano-LC-MS/MS. MaxQuant/Andromeda search of the MS data against the non-redundant (nr) GenBank database and a G. morsitans morsitans SG EST database, yielded a total of 521 hits, 31 of which were SGHV-encoded. On a false discovery rate limit of 1% and detection threshold of least 2 unique peptides per protein, the analysis resulted in 292 Glossina and 25 SGHV MS-supported proteins. When annotated by the Blast2GO suite, at least one gene ontology (GO) term could be assigned to 89.9% (285/317) of the detected proteins. Five (∼1.8%) Glossina and three (∼12%) SGHV proteins remained without a predicted function after blast searches against the nr database. Sixty-five of the 292 detected Glossina proteins contained an N-terminal signal/secretion peptide sequence. Eight of the SGHV proteins were predicted to be non-structural (NS), and fourteen are known structural (VP) proteins.

Conclusions/Significance

SGHV alters the protein expression pattern in Glossina. The G. pallidipes SG secretome encompasses a spectrum of proteins that may be required during the SGHV infection cycle. These detected proteins have putative interactions with at least 21 of the 25 SGHV-encoded proteins. Our findings opens venues for developing novel SGHV mitigation strategies to block SGHV infections in tsetse production facilities such as using SGHV-specific antibodies and phage display-selected gut epithelia-binding peptides.     

Detection of protease-resistant cervid prion protein in water from a CWD-endemic area

Chronic wasting disease (CWD) is the only known transmissible spongiform encephalopathy affecting free-ranging wildlife. Although the exact mode of natural transmission remains unknown, substantial evidence suggests that prions can persist in the environment, implicating components thereof as potential prion reservoirs and transmission vehicles.^1–4 CWD-positive animals may contribute to environmental prion load via decomposing carcasses and biological materials including saliva, blood, urine and feces.^5–7 Sensitivity limitations of conventional assays hamper evaluation of environmental prion loads in soil and water. Here we show the ability of serial protein misfolding cyclic amplification (sPMCA) to amplify a 1.3 × 10⁻⁷ dilution of CWD-infected brain homogenate spiked into water samples, equivalent to approximately 5 × 10⁷ protease resistant cervid prion protein (PrP^CWD) monomers. We also detected PrP^CWD in one of two environmental water samples from a CWD endemic area collected at a time of increased water runoff from melting winter snow pack, as well as in water samples obtained concurrently from the flocculation stage of water processing by the municipal water treatment facility. Bioassays indicated that the PrP^CWD detected was below infectious levels. These data demonstrate detection of very low levels of PrP^CWD in the environment by sPMCA and suggest persistence and accumulation of prions in the environment that may promote CWD transmission.Key words: prions, chronic wasting disease, water, environment, serial protein misfolding cyclic amplification