Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease.

Late blight is a serious economic threat to potato crop, sometimes leading to complete crop loss. The resistance in potato to late blight can be qualitative or quantitative in nature. Qualitative resistance is not durable. Though quantitative resistance is durable, the breeding is challenging due to polygenic inheritance. Several quantitative trait loci (QTLs) have been identified, but the mechanisms of resistance are largely unknown. A nontargeted metabolomics approach was used to identify resistance-related (RR) metabolites in a resistant genotype (F06025), as compared to a susceptible (Shepody) genotype, mock- or pathogen-inoculated. The RR metabolites, which had high fold change in abundance, mainly belonged to phenylpropanoid, flavonoid, fatty acid, and alkaloid chemical groups. The most important phenylpropanoids identified were hydroxycinnamic acid amides, the polyaromatic domain of suberin that is known to be associated with cell wall reinforcement. These metabolites were mapped on to the potato metabolic pathways, and the candidate enzymes and their coding genes were identified. A quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay revealed a higher upregulation of 4-coumarate: CoA ligase (4-CL), tyrosine decarboxylase (TyDC), and tyramine hydroxycinnamoyl transferase (THT) in the pathogen-inoculated resistant genotype than in susceptible. These genes were sequenced in both resistant and susceptible genotypes, and nonsynonymous single-nucleotide polymorphisms (nsSNPs) were found. The application of these genes in potato resistance improvement, following validation, is discussed.

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This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. Potato (Solanum tuberosum L.) is one of the most important food crops in the world and provides essential nutrients. With an aim to develop potato varieties for functional food or nutraceutial applications, we have conducted metabolomic profiling, total phenolics, chlorogenic acid, anthocyanins, and glycoalkaloids analyses on 20 selected potato clones within the Canadian potato breeding program of Agriculture and Agri-Food Canada. Pigmented potatoes in general contain higher levels of phenolic components, including chlorogenic acid and anthocyanins. Levels of phenolics were retained with granulation processing of pigmented potato tubers, but glycoalkaloids were significantly reduced with granulation. The pigmented potatoes also have higher antioxidant activity reaching up to 35% of that for berries, measured as their potency in scavenging DPPH radicals. Extracts of the 20 potato clones (peel, tuber, and granule) were also evaluated for in vitro effects on liver LDL cholesterol uptake and protection of cortical neurons from cell death caused by oxygen glucose deprivation (OGD). These potato extracts in general showed mild activity in enhancing LDL cholesterol uptake in liver HepG2 cells, and also protected cortical neurons against OGD induced cell death, with extracts from granules of six of the potato clones showing significant neuroprotective effects. The bioactive components are not dependent on pigmentation of potato clones. These novel bioactivities identified in potatoes warrant in-depth investigations in the future. Taken together, our results provide further evidence for the enhanced health beneficial components in potato. Crown