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The hop plant (Humulus lupulus L.) has been exploited for a long time for both its brewing and medicinal uses, due in particular to its specific chemical composition. These last years, hop cultivation that was in decline has been experiencing a renewal for several reasons, such as a craze for strongly hopped aromatic beers. In this context, the present work aims at investigating the genetic and chemical diversity of fifty wild hops collected from different locations in Northern France. These wild hops were compared to ten commercial varieties and three heirloom varieties cultivated in the same sampled geographical area. Genetic analysis relying on genome fingerprinting using 11 microsatellite markers showed a high level of diversity. A total of 56 alleles were determined with an average of 10.9 alleles per locus and assessed a significant population structure (mean pairwise F ST  = 0.29). Phytochemical characterization of hops was based on volatile compound analysis by HS-SPME GC-MS, quantification of the main prenylated phenolic compounds by UHPLC-UV as well as untargeted metabolomics by UHPLC-HRMS and revealed a high level of chemical diversity among the assessed wild accessions. In particular, analysis of volatile compounds revealed the presence of some minor but original compounds, such as aromadendrene, allo-aromadendrene, isoledene, β-guaiene, α-ylangene and β-pinene in some wild accessions; while analysis of phenolic compounds showed high content of β-acids in these wild accessions, up to 2.37% of colupulone. Genetic diversity of wild hops previously observed was hence supported by their chemical diversity. Sample soil analysis was also performed to get a pedological classification of these different collection sites. Results of the multivariate statistical analysis suggest that wild hops constitute a huge pool of chemical and genetic diversity of this species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The O-linked-N-acetyl-d-glucosaminylation (O-GlcNAcylation) modulates numerous aspects of cellular processes. Akin to phosphorylation, O-GlcNAcylation is highly dynamic, reversible, and responds rapidly to extracellular demand. Despite the absolute necessity to determine post-translational sites to fully understand the role of O-GlcNAcylation, it remains a high challenge for the major reason that unmodified proteins are in excess comparing to the O-GlcNAcylated ones. Based on a click chemistry approach, O-GlcNAcylated proteins were labelled with azido-GalNAc and coupled to agarose beads. The proteome extracted from C2C12 myotubes was submitted to an intensive fractionation prior to azide-alkyne click chemistry. This combination of fractionation and click chemistry is a powerful methodology to map O-GlcNAc sites; indeed, 342 proteins were identified through the identification of 620 peptides containing one or more O-GlcNAc sites. We localized O-GlcNAc sites on proteins involved in signalling pathways or in protein modification, as well as structural proteins. Considering the recent role of O-GlcNAcylation in the modulation of sarcomere morphometry and interaction between key structural protein, we focused on proteins involved in the cytoarchitecture of skeletal muscle cells. In particular, several O-GlcNAc sites were located into protein-protein interaction domains, suggesting that O-GlcNAcylation could be strongly involved in the organization and reorganization of sarcomere and myofibrils., Significance: O-GlcNAcylation is an atypical glycosylation involved in the regulation of almost all if not all cellular processes, but its precise role remains sometimes obscure because of the ignorance of the O-GlcNAc site localization; thus, it remains indispensable to precisely map the O-GlcNAcylated sites to fully understand the role of O-GlcNAcylation on a given protein. For this purpose, we combined extensive fractionation of skeletal muscle cells proteome with click chemistry to map O-GlcNAc sites without an a priori consideration. A total of 620 peptides containing one or more O-GlcNAc sites were identified; interestingly, several of them belong to low expressed proteins, in particular proteins involved in signalling pathways. We also focused on structural proteins in view of recent data supporting the role of O-GlcNAcylation in the modulation of sarcomere cytoarchitecture; importantly, some of the O-GlcNAc sites were mapped into protein-protein interaction domains, reinforcing the involvement of O-GlcNAcylation in the organization and reorganization of sarcomere, and in larger extent, of myofibrils., (Copyright © 2018 Elsevier B.V. All rights reserved.)

When in the vicinity of astrocytes, brain capillary endothelial cells (BCECs) develop the characteristic structural and functional features of the blood-brain barrier (BBB). The latter has low cellular permeability and restricts various compounds from entering the brain. We recently reported that the cytoskeleton-related proteins actin, gelsolin and filamin-A undergo the largest quantitative changes in bovine BCECs after re-induction of BBB functions by co-culture with glial cells. In the present study, we used an in-depth, proteomic approach to quantitatively compare differences in Triton-X-100-solubilized proteins from bovine BCECs with limited or re-induced BBB functions (i.e. cultured in the absence or presence of glial cells, respectively). The 81 protein spots of differing abundance were linked to 55 distinct genes. According to the Protein ANalysis THrough Evolutionary Relationships classification system and an Ingenuity Pathway Analysis, these quantitative changes mainly affected proteins involved in (i) cell structure and motility and (ii) protein metabolism and modification. The fold-changes affecting HSPB1, moesin and ANXA5 protein levels were confirmed by western blot analysis but were not accompanied by changes in the corresponding mRNA expression levels. Our results reveal that the bovine BCECs' phenotype adaptation to variations in their environment involves the reorganization of the actin cytoskeleton., (Copyright © 2011 Elsevier B.V. All rights reserved.)