[Abstract unavailable

We densely genotyped, using 1000 Genomes Project pilot CEU and additional re-sequencing study variants, 183 reported immune-mediated disease non-HLA risk loci in 12,041 celiac disease cases and 12,228 controls. We identified 13 new celiac disease risk loci at genome wide significance, bringing the total number of known loci (including HLA) to 40. Multiple independent association signals are found at over a third of these loci, attributable to a combination of common, low frequency, and rare genetic variants. In comparison with previously available data such as HapMap3, our dense genotyping in a large sample size provided increased resolution of the pattern of linkage disequilibrium, and suggested localization of many signals to finer scale regions. In particular, 29 of 54 fine-mapped signals appeared localized to specific single genes - and in some instances to gene regulatory elements. We define a complex genetic architecture of risk regions, and refine risk signals, providing a next step towards elucidating causal disease mechanisms.

Several natural compounds found in health-related food items can inhibit acetyltransferases as they induce autophagy. Here we show that this applies to anacardic acid, curcumin, garcinol and spermidine, all of which reduce the acetylation level of cultured human cells as they induce signs of increased autophagic flux (such as the formation of green fluorescent protein-microtubuleassociated protein 1A/1B-light chain 3 (GFP-LC3) puncta and the depletion of sequestosome-1, p62/SQSTM1) coupled to the inhibition of the mammalian target of rapamycin complex 1 (mTORC1). We performed a screen to identify the acetyltransferases whose depletion would activate autophagy and simultaneously inhibit mTORC1. The knockdown of only two acetyltransferases (among 43 candidates) had such effects: EP300 (E1A-binding protein p300), which is a lysine acetyltranferase, and NAA20 (N(α)-acetyltransferase 20, also known as NAT5), which catalyzes the N-terminal acetylation of methionine residues. Subsequent studies validated the capacity of a pharmacological EP300 inhibitor, C646, to induce autophagy in both normal and enucleated cells (cytoplasts), underscoring the capacity of EP300 to repress autophagy by cytoplasmic (non-nuclear) effects. Notably, anacardic acid, curcumin, garcinol and spermidine all inhibited the acetyltransferase activity of recombinant EP300 protein in vitro. Altogether, these results support the idea that EP300 acts as an endogenous repressor of autophagy and that potent autophagy inducers including spermidine de facto act as EP300 inhibitors. Macroautophagy (herein referred to as 'autophagy') consist in the sequestration of cytoplasmic material in autophagosomes, followed by their fusion with lysosomes for the bulk degradation of autophagic cargo by lysosomal hydrolases.1 This phenomenon can be measured by following the redistribution of green fluorescent protein-microtubule-associated protein 1A/1B-light chain 3 (GFP-LC3) fusion proteins from a diffuse location to autophagosomes (that results in the formation of the so-called GFP-LC3 'puncta'), the diminution of the overall abundance of autophagic substrates (such as sequestosome-1, p62/SQSTM1), and the stereotyped activation of proautophagic signals (such as the inhibition of the mammalian target of rapamycin complex 1, mTORC1). 2There is growing consensus that the induction of autophagy by nutritional, pharmacological or genetic interventions can reduce age-related pathologies (such as neurodegenerative diseases or type 2 diabetes) and/or extend longevity. [3][4][5][6] This applies to caloric restriction or intermediate fasting, 7 continuous or intermittent medication of rapamycin, [8][9][10] administration of the sirtuin 1-activator resveratrol, 11,12 external supply of the polyamine spermidine, 13 or genetic ablation of p53.14 In all these cases, inhibition of autophagy by deleting or silencing relevant genes abolishes the extension of health span and/or lifespan. [13][14][15][16][17] Moreover, direct induction of autophagy by transgenic expression of autophag...

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To obtain mechanistic insights into the cross talk between lipolysis and autophagy, two key metabolic responses to starvation, we screened the autophagy-inducing potential of a panel of fatty acids in human cancer cells. Both saturated and unsaturated fatty acids such as palmitate and oleate, respectively, triggered autophagy, but the underlying molecular mechanisms differed. Oleate, but not palmitate, stimulated an autophagic response that required an intact Golgi apparatus. Conversely, autophagy triggered by palmitate, but not oleate, required AMPK, PKR and JNK1 and involved the activation of the BECN1/PIK3C3 lipid kinase complex. Accordingly, the downregulation of BECN1 and PIK3C3 abolished palmitate-induced, but not oleate-induced, autophagy in human cancer cells. Moreover, Becn1 +/À mice as well as yeast cells and nematodes lacking the ortholog of human BECN1 mounted an autophagic response to oleate, but not palmitate.Thus, unsaturated fatty acids induce a non-canonical, phylogenetically conserved, autophagic response that in mammalian cells relies on the Golgi apparatus.

Autophagy constitutes a prominent mechanism through which eukaryotic cells preserve homeostasis in baseline conditions and in response to perturbations of the intracellular or extracellular microenvironment. Autophagic responses can be relatively non-selective or target a specific subcellular compartment. At least in part, this depends on the balance between the availability of autophagic substrates ("offer") and the cellular need of autophagic products or functions for adaptation ("demand"). Irrespective of cargo specificity, adaptive autophagy relies on a panel of sensors that detect potentially dangerous cues and convert them into signals that are ultimately relayed to the autophagic machinery. Here, we summarize the molecular systems through which specific subcellular compartments-including the nucleus, mitochondria, plasma membrane, reticular apparatus, and cytosol-convert homeostatic perturbations into an increased offer of autophagic substrates or an accrued cellular demand for autophagic products or functions.

A sizeable proportion of asymptomatic potential celiac patients showed fluctuation or negativization of antibody production, and many of these, with persistently positive anti-TG2, did not develop mucosal damage after 9 years of follow-up. Celiac population is a multivariate aggregate of individuals with different genetic and phenotypic profiles. Caution is required before prescribing a gluten-free diet for life to asymptomatic individuals with potential CD.