Signalling Pathways Implicated in Obesity Associated Cancers

Grant support: The Scottish Government's Rural and Environment Science and Analytical Services Division. Declaration of interest: The author declares that there is no conflict of interest.Peer reviewedPublisher PD

Cloning and characterisation of genes determining pod morphology in pea

Genes expressed in developing pea pods were isolated as cDNAs by differential screening techniques. The cDNAs were characterised by DNA sequencing and expression studies were used to investigate the role of isolated cDNAs in pod development. A clone isolated from a pea {Piswn sativum L.) pod cDNA library was shown to contain the complete coding sequence of a polypeptide with considerable homology to various members of the Rab subfamily of small ras-related GTP- binding proteins. Conserved sequences in the isolated clone include the GTP-buiding site, GDP/GTP hydrolysis domain and C-terminal Cys residues involved in membrane attachment. The high percentage amino acid identity suggests that this cDNA may be the product of a gene, designated Psa-rai?, which is the plant counterpart of Rab7. Rab/Ypt proteins are thought to be involved in intracellular transport from the endoplasmic reticulum to the Golgi apparatus and in vesicular transport. If Psa-ra6 is a functional counterpart of yeast YPT7 (RabT) it should be able to complement a yeast YPT7 mutant. An attempt was made to demonstrate that this was the case. Northern analysis showed invariant expression of Psa-rab in developing pods 'with different phenotypes, indicating an essential function for Psa-rab in developing pods. Hybridisation of the Psa-rab cDNA to pea genomic DNA showed that this protein is probably encoded by a single gene. Nearly isogenic pea lines were selected to investigate the genetic basis for lignification of the pea {Pisum sativum L.) pod endocarp. The development of the pod endocarp in the normal and mutant pea pod phenotypes was examined by histochemical staining and light microscopy. The effect of plant growth regulators on endocarp development was also investigated. A pea pod cDNA library representing poly (A)+ RNA purified from L59 pea pods (genotype, PV; phenotype, lignified endocarp) was differentially screened with total cDNA probes prepared from total pod RNA from L59 and LI390 (genotype, PV; phenotype, no lignification of endocarp) pods 4-6 days after flowering (DAP). Two clones, designated pLP18 and pLP19, were selected for further characterisation on the basis of hybridisation to the L59 cDNA probe, but not the LI390 cDNA probe. Northern blotting was used to show that pLP18 represented a mRNA of 0.95 kb. The predicted polypeptide from the LP18 cDNA encoded a putative blue type I copper protein. The expression pattern of LP 18 mRNA in pods and tissues of the experimental pea lines was determined using RT-PCR quantitation. Hybridisation of the cDNA to pea genomic DNA showed that this protein is probably encoded by a single gene. Clone pLP19 yielded a 1.02 kb cDNA fragment encoding the C-terminal portion of an Hsp70 homologue belonging to a highly conserved family of proteins found in a number of eukaryotic species. Northern analysis of RNA from lignified and unlignified pods showed the presence of differentially expressed LP19 transcripts of varying lengths, which may represent differently processed transcripts. Southern analysis confirmed the presence of a single hybridised band in genomic digests of L59, L58 arid LI390. Several mRNA transcripts of the LP19 gene were isolated which differ in the length of their- 3' untranslated regions

Challenges of the heterogeneous nutrition response : interpreting the group mean

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Tissue-specific regulation of sirtuin and nicotinamide adenine dinucleotide biosynthetic pathways identified in C57Bl/6 mice in response to high-fat feeding

Funding: The Scottish Government's Rural and Environment Science and Analytical Services Division.Peer reviewedPostprin

Differential coupling of the extreme C-terminus of G protein α subunits to the G protein-coupled melatonin receptors

AbstractMelatonin receptors interact with pertussis toxin-sensitive G proteins to inhibit adenylate cyclase. However, the G protein coupling profiles of melatonin receptor subtypes have not been fully characterised and alternative G protein coupling is evident. The five C-terminal residues of Gα subunits confer coupling specificity to G protein-coupled receptors. This report outlines the use of Gαs chimaeras to alter the signal output of human melatonin receptors and investigate their interaction with the C-termini of Gα subunits. The Gαs portion of the chimaeras confers the ability to activate adenylate cyclase leading to cyclic AMP production. Co-transfection of HEK293 cells expressing MT1 or MT2 melatonin receptors with Gαs chimaeras and a cyclic AMP activated luciferase construct provided a convenient and sensitive assay system for identification of receptor recognition of Gα C-termini. Luciferase assay sensitivity was compared with measurement of cyclic AMP elevations by radioimmunoassay. Differential interactions of the melatonin receptor subtypes with Gα chimaeras were observed. Temporal and kinetic parameters of cyclic AMP responses measured by cyclic AMP radioimmunoassay varied depending on the Gαs chimaeras coupled. Recognition of the C-terminal five amino acids of the Gα subunit is a requisite for coupling to a receptor, but it is not the sole determinant

The TLR4 D299G and T399I SNPs Are Constitutively Active to Up-Regulate Expression of Trif-Dependent Genes

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Inter-individual variation in postprandial glycaemic responses in women co-ingesting green leafy vegetables with a carbohydrate meal : interactions with the sirtuin system

The authors acknowledge the support of the Scottish Government Rural and Environment Science and Analytical Services (RESAS) Strategic Research Programme. Clinical biochemistry lab at the Foresterhill hospital for analysing sex hormone samples, Human Nutrition Unit staff and analytical staff and the Rowett Institute, University of Aberdeen and Alex Stewart for providing the compositional information for the meal interventions used. Finally, we would like to thank the volunteers participating in VegGI study. Open access via Wiley agreementPeer reviewedPublisher PD

Semiautomated Glasgow-Blatchford Bleeding Score helps direct bed placement for patients with upper gastrointestinal bleeding.

OBJECTIVE: The Glasgow-Blatchford Bleeding Score (GBS) was designed to identify patients with upper gastrointestinal bleeding (UGIB) who do not require hospitalisation. It may also help stratify patients unlikely to benefit from intensive care. DESIGN: We reviewed patients assigned a GBS in the emergency room (ER) via a semiautomated calculator. Patients with a score ≤7 (low risk) were directed to an unmonitored bed (UMB), while those with a score of ≥8 (high risk) were considered for MB placement. Conformity with guidelines and subsequent transfers to MB were reviewed, along with transfusion requirement, rebleeding, length of stay, need for intervention and death. RESULTS: Over 34 months, 1037 patients received a GBS in the ER. 745 had an UGIB. 235 (32%) of these patients had a GBS ≤7. 29 (12%) low-risk patients were admitted to MBs. Four low-risk patients admitted to UMB required transfer to MB within the first 48 hours. Low-risk patients admitted to UMBs were no more likely to die, rebleed, need transfusion or require more endoscopic, radiographic or surgical procedures than those admitted to MBs. No low-risk patient died from GIB. Patients with GBS ≥8 were more likely to rebleed, require transfusion and interventions to control bleeding but not to die. CONCLUSION: A semiautomated GBS calculator can be incorporated into an ER workflow. Patients with a GBS ≤7 are unlikely to need MB care for UGIB. Further studies are warranted to determine an ideal scoring system for MB admission

SIV antigen immunization induces transient antigen-specific T cell responses and selectively activates viral replication in draining lymph nodes in retroviral suppressed rhesus macaques

<p>Abstract</p> <p>Background</p> <p>HIV infection causes a qualitative and quantitative loss of CD4⁺T cell immunity. The institution of anti-retroviral therapy (ART) restores CD4⁺T cell responses to many pathogens, but HIV-specific responses remain deficient. Similarly, therapeutic immunization with HIV antigens of chronically infected, ART treated subjects results in poor induction of HIV-specific CD4 responses. In this study, we used a macaque model of ART treatment during chronic infection to study the virologic consequences of SIV antigen stimulation in lymph nodes early after immunization. Rhesus CMV (RhCMV) seropositive, Mamu A*01 positive rhesus macaques were chronically infected with SIVmac251 and treated with ART. The immune and viral responses to SIV gag and RhCMV pp65 antigen immunization in draining lymph nodes and peripheral blood were analyzed. Animals were immunized on contralateral sides with SIV gag and RhCMV pp65 encoding plasmids, which allowed lymph nodes draining each antigen to be obtained at the same time from the same animal for direct comparison.</p> <p>Results</p> <p>We observed that both SIV and RhCMV immunizations stimulated transient antigen-specific T cell responses in draining lymph nodes. The RhCMV-specific responses were potent and sustained (50 days post-immunization) in the periphery, while the SIV-specific responses were transient and extinguished quickly. The SIV antigen stimulation selectively induced transient SIV replication in draining lymph nodes.</p> <p>Conclusions</p> <p>The data are consistent with a model whereby viral replication in response to SIV antigen stimulation limits the generation of SIV antigen-specific responses and suggests a potential mechanism for the early loss and poor HIV-specific CD4⁺T cell response observed in HIV-infected individuals.</p

Molecular profiling of multiplexed gene markers to assess viability of ex vivo human colon explant cultures

© Janice E. Drew et al. 2015; Published by Mary Ann Liebert, Inc. This Open Access article is distributed under the terms of the Creative Commons License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. Acknowledgments The authors would like to thank the patients who kindly donated tissue samples, Sally Chalmers of the Tayside Tissue Bank for her help with collecting of the tissue donor samples, Emma Moss for advice on human colon dissection and explant culture, and Claus Dieter Mayer, Biomathematics and Statistics Scotland, for advice on statistical analysis. This work was supported by the Scottish Government (GT403), Scottish Universities Life Science Alliance, and TENOVUS Scotland.Peer reviewedPublisher PD