BioMed Research International

Wong, Victor W.;Sorkin, Michael;Glotzbach, Jason P.;Longaker, Michael T.;Gurtner, Geoffrey C.

doi: 10.1155/2011/969618pmid: 21151647

Wound repair is a complex biologic process which becomes abnormal in numerous disease states. Although <i>in vitro</i> models have been important in identifying critical repair pathways in specific cell populations, <i>in vivo</i> models are necessary to obtain a more comprehensive and pertinent understanding of human wound healing. The laboratory mouse has long been the most common animal research tool and numerous transgenic strains and models have been developed to help researchers study the molecular pathways involved in wound repair and regeneration. This paper aims to highlight common surgical mouse models of cutaneous disease and to provide investigators with a better understanding of the benefits and limitations of these models for translational applications.

Figueroa, Debbie M.;Davis, James D.;Strobel, Cornelia;Conejo, Maria S.;Beckham, Katherine D.;Ring, Brian C.;Bass, Hank W.

doi: 10.1155/2011/386862pmid: 21234422

The integration of genetic and physical maps of maize is progressing rapidly, but the cytogenetic maps lag behind, with the exception of the pachytene fluorescence <i>in situ</i> hybridization (FISH) maps of maize chromosome 9. We sought to produce integrated FISH maps of other maize chromosomes using Core Bin Marker loci. Because these 1 Kb restriction fragment length polymorphism (RFLP) probes are below the FISH detection limit, we used BACs from sorghum, a small-genome relative of maize, as surrogate clones for FISH mapping. We sequenced 151 maize RFLP probes and compared <i>in silico</i> BAC selection methods to that of library filter hybridization and found the latter to be the best. BAC library screening, clone verification, and single-clone selection criteria are presented along with an example of transgenomic BAC FISH mapping. This strategy has been used to facilitate the integration of RFLP and FISH maps in other large-genome species.

Lin, Jinke;Kudrna, Dave;Wing, Rod A.

doi: 10.1155/2011/476723pmid: 21234344

We describe the construction and characterization of a publicly available BAC library for the tea plant, <i >Camellia sinensis</i>. Using modified methods, the library was constructed with the aim of developing public molecular resources to advance tea plant genomics research. The library consists of a total of 401,280 clones with an average insert size of 135&#x2009;kb, providing an approximate coverage of 13.5 haploid genome equivalents. No empty vector clones were observed in a random sampling of 576 BAC clones. Further analysis of 182 BAC-end sequences from randomly selected clones revealed a GC content of 40.35&#x25; and low chloroplast and mitochondrial contamination. Repetitive sequence analyses indicated that LTR retrotransposons were the most predominant sequence class (86.93&#x25;&#x2013;87.24&#x25;), followed by DNA retrotransposons (11.16&#x25;&#x2013;11.69&#x25;). Additionally, we found 25 simple sequence repeats (SSRs) that could potentially be used as genetic markers.

Masumi, Atsuko

doi: 10.1155/2011/640610pmid: 21234331

When studying transcription factors, it is necessary to investigate posttranslational modifications. Histone acetyltransferases (HATs) are typical of the modification enzymes involved in chromatin regulation. HATs acetylate the transcription factors (nonhistone proteins) as well as histones. Interferon regulatory factors (IRFs) are transcription factors that bind to the interferon regulatory element (IRF-E) and are involved in regulating cell growth, differentiation, and the immune and hematopoietic systems. During the process of binding to a specific DNA element, IRFs also bind to coactivators such as HATs and become modified. This review looks at how IRFs associate with HATs, p300, and PCAF, and thereby contribute to transcriptional activation.

Yao, Ya-Li;Yang, Wen-Ming

doi: 10.1155/2011/146493pmid: 21234400

Acetylation of lysines is a prominent form of modification in mammalian proteins. Deacetylation of proteins is catalyzed by histone deacetylases, traditionally named after their role in histone deacetylation, transcriptional modulation, and epigenetic regulation. Despite the link between histone deacetylases and chromatin structure, some of the histone deacetylases reside in various compartments in the cytoplasm. Here, we review how these cytoplasmic histone deacetylases are regulated, the identification of nonhistone substrates, and the functional implications of their nondeacetylase enzymatic activities.

Shahrizaila, Nortina;Yuki, Nobuhiro

doi: 10.1155/2011/829129pmid: 21197269

Molecular mimicry between self and microbial components has been proposed as the pathogenic mechanism of autoimmune diseases, and this hypothesis is proven in Guillain-Barré syndrome. Guillain-Barré syndrome, the most frequent cause of acute neuromuscular paralysis, sometimes occurs after <i>Campylobacter jejuni</i> enteritis. Gangliosides are predominantly cell-surface glycolipids highly expressed in nervous tissue, whilst lipo-oligosaccharides are major components of the Gram-negative bacterium <i>C. jejuni</i> outer membrane. IgG autoantibodies to GM1 ganglioside were found in the sera from patients with Guillain-Barré syndrome. Molecular mimicry was demonstrated between GM1 and lipo-oligosaccharide of <i>C. jejuni</i> isolated from the patients. Disease models by sensitization of rabbits with GM1 and <i>C. jejuni</i> lipo-oligosaccharide were established. Guillain-Barré syndrome provided the first verification that an autoimmune disease is triggered by molecular mimicry. Its disease models are helpful to further understand the molecular pathogenesis as well as to develop new treatments in Guillain-Barré syndrome.

Tunster, S. J.;Van De Pette, M.;John, R. M.

doi: 10.1155/2011/283013pmid: 21197393

Genomic imprinting in mammals results in the expression of genes from only one parental allele. Imprinting occurs as a consequence of epigenetic marks set down either in the father's or the mother's germ line and affects a very specific category of mammalian gene. A greater understanding of this distinctive phenomenon can be gained from studies using large genomic clones, called bacterial artificial chromosomes (BACs). Here, we review the important applications of BACs to imprinting research, covering physical mapping studies and the use of BACs as transgenes in mice to study gene expression patterns, to identify imprinting centres, and to isolate the consequences of altered gene dosage. We also highlight the significant and unique advantages that rapid BAC engineering brings to genomic imprinting research.

Wu, Ting-Ting;Liao, Hsiang-I;Tong, Leming;Leang, Ronika Sitapara;Smith, Greg;Sun, Ren

doi: 10.1155/2011/926258pmid: 21197474

Here we describe the cloning of a sequenced WUMS isolate of murine gammaherpesvirus-68 (MHV-68, γHV-68, also known as MuHV-4) as a bacterial artificial chromosome (BAC). We engineered the insertion of the BAC sequence flanked by loxP sites into the left end of the viral genome before the M1 open reading frame. The infectious viruses were reconstituted following transfection of the MHV-68 BAC DNA into cells. The MHV-68 BAC-derived virus replicated indistinguishably from the wild-type virus in cultured cells. Excision of the BAC insert was efficiently achieved by coexpressing the Cre recombinase. Although the BAC insertion did not significantly affect acute productive infection in the lung, it severely compromised the ability of MHV-68 to establish splenic latency. Removal of the BAC sequence restored the wild-type level of latency. Site-specific mutagenesis was carried out by RecA-mediated recombination to demonstrate that this infectious BAC clone can be used for genetic studies of MHV-68.

Mizutani, Shigehiko;Wright, John W.;Kobayashi, Hiroshi

doi: 10.1155/2011/286947pmid: 21188170

Preeclampsia and preterm delivery are important potential complications in pregnancy and represent the leading causes for maternal and perinatal morbidity and mortality. The mechanisms underlying both diseases remain unknown, thus available treatments (beta2-stimulants and magnesium sulfate) are essentially symptomatic. Both molecules have molecular weights less than 5&#8211;8&#x2009;kDa, cross the placental barrier, and thus exert their effects on the fetus. The fetus produces peptides that are highly vasoactive and uterotonic and increase in response to maternal stress and with continued development. Fetal peptides are also small molecules that inevitably leak across into the maternal circulation. Aminopeptidases such as placental leucine aminopeptidase (P-LAP) and aminopeptidase A (APA) are large molecules that do not cross the placental barrier. We have shown that APA acts as an antihypertensive agent in the pregnant spontaneously hypertensive rat by degrading vasoactive peptides and as a result returns the animal to a normotensive state. P-LAP also acts as an antiuterotonic agent by degrading uterotonic peptides and thus prolongs gestation in the pregnant mouse. Given the ever increasing worldwide incidences of preeclampsia and preterm labor, it is imperative that new agents be developed to safely prolong gestation. We believe that the use of aminopeptidases hold promise in this regard.

Lei, Jilin;Bi, Yuhua;Shen, Lizhong

doi: 10.1155/2011/417421pmid: 21234367

In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel engine fueled with pure diesel (as prototype) and ethanol-diesel blends (E10, E15, E20 and E30) under different atmospheric pressures (81 kPa, 90 kPa and 100 kPa). The experimental results indicate that the equivalent brake-specific fuel consumption (BSFC) of ethanol-diesel blends are better than that of diesel under different atmospheric pressures and that the equivalent BSFC gets great improvement with the rise of atmospheric pressure when the atmospheric pressure is lower than 90 kPa. At 81 kPa, both HC and CO emissions rise greatly with the increasing engine speeds and loads and addition of ethanol, while at 90 kPa and 100 kPa their effects on HC and CO emissions are slightest. The changes of atmospheric pressure and mix proportion of ethanol have no obvious effect on NO_x emissions. Smoke emissions decrease obviously with the increasing percentage of ethanol in blends, especially atmospheric pressure below 90 kPa.