Project description:Chronic pain is a global public health problem, but the underlying molecular mechanisms are not fully understood. Here we examine genome-wide DNA methylation, first in 50 identical twins discordant for heat pain sensitivity and then in 50 further unrelated individuals. Whole blood DNA methylation was characterized at 5.2 million loci by MeDIP-sequencing and assessed longitudinally to identify differentially methylated regions associated with high or low pain-sensitivity (pain-DMRs). Nine meta-analysis pain-DMRs show robust evidence for association (false discovery rate 5%) with the strongest signal in the pain gene TRPA1 (P=1.2×10-13). Several pain-DMRs show longitudinal stability consistent with susceptibility effects, have similar methylation levels in brain, and altered expression in skin. Our approach identifies epigenetic changes in both novel and established candidate genes that provide molecular insights into pain and may generalize to other complex traits.
Project description:Chronic pain is a global public health problem, but the underlying molecular mechanisms are not fully understood. Here we examine genome-wide DNA methylation, first in 50 identical twins discordant for heat pain sensitivity and then in 50 further unrelated individuals. Whole-blood DNA methylation was characterized at 5.2 million loci by MeDIP sequencing and assessed longitudinally to identify differentially methylated regions associated with high or low pain sensitivity (pain DMRs). Nine meta-analysis pain DMRs show robust evidence for association (false discovery rate 5%) with the strongest signal in the pain gene TRPA1 (P=1.2 × 10(-13)). Several pain DMRs show longitudinal stability consistent with susceptibility effects, have similar methylation levels in the brain and altered expression in the skin. Our approach identifies epigenetic changes in both novel and established candidate genes that provide molecular insights into pain and may generalize to other complex traits.
Project description:Genome wide DNA methylation profiling of normal whole blood samples. The data consist of 43 samples with Illumina HumanMethylation450 BeadChip data.
Project description:Chronic pain is a global public health problem, but the underlying molecular mechanisms are not fully understood. Here we examine genome-wide DNA methylation, first in 50 identical twins discordant for heat pain sensitivity and then in 50 further unrelated individuals. Whole blood DNA methylation was characterized at 5.2 million loci by MeDIP-sequencing and assessed longitudinally to identify differentially methylated regions associated with high or low pain-sensitivity (pain-DMRs). Nine meta-analysis pain-DMRs show robust evidence for association (false discovery rate 5%) with the strongest signal in the pain gene TRPA1 (P=1.2M-CM-^W10-13). Several pain-DMRs show longitudinal stability consistent with susceptibility effects, have similar methylation levels in brain, and altered expression in skin. Our approach identifies epigenetic changes in both novel and established candidate genes that provide molecular insights into pain and may generalize to other complex traits. MeDIP-sequencing in 100 individulas using a 2 stage design: paired-end MeDIP-seq in 50 monozygotic twins and single-end MeDIP-seq in 50 unrelated individuals.
Project description:Genome wide DNA methylation profiling of normal whole blood samples. The data consist of 43 samples with Illumina HumanMethylation450 BeadChip data. Bisulphite converted DNA from 43 of these samples were hybridized to the Illumina Infinium 450k Human Methylation Beadchip.
Project description:TRPM8 (transient receptor potential M8) and TRPA1 (transient receptor potential A1) are cold-temperature-sensitive nociceptors expressed in sensory neurons but their behaviour in neuronal cells is poorly understood. Therefore DNA expression constructs containing human TRPM8 or TRPA1 cDNAs were transfected into HEK (human embryonic kidney cells)-293 or SH-SY5Y neuroblastoma cells and G418 resistant clones analysed for effects of agonists and antagonists on intracellular Ca2+ levels. Approximately 51% of HEK-293 and 12% of SH-SY5Y cell clones expressed the transfected TRP channel. TRPM8 and TRPA1 assays were inhibited by probenecid, indicating the need to avoid this agent in TRP channel studies. A double-residue mutation in ICL-1 (intracellular loop-1) of TRPM8 (SV762,763EL, mimicking serine phosphorylation) or one in the C-terminal tail region (FK1045,1046AG, a lysine knockout) retained sensitivity to agonists (WS 12, menthol) and antagonist {AMTB [N-(3-Aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)benzamide]}. SNP (single nucleotide polymorphism) variants in TRPA1 ICL-1 (R797T, S804N) and TRPA1 fusion protein containing C-terminal (His)10 retained sensitivity to agonists (cinnamaldehyde, allyl-isothiocyanate, carvacrol, eugenol) and antagonists (HC-030031, A967079). One SNP variant, 797T, possessed increased sensitivity to agonists. TRPA1 became repressed in SH-SY5Y clones but was rapidly rescued by Src-family inhibitor PP2 [4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine]. Conversely, TRPM8 in SH-SY5Y cells was inhibited by PP2. Further studies utilizing SH-SY5Y may identify structural features of TRPA1 and TRPM8 involved in conferring differential post-translational regulation.