15 results on '"Campbell BJ"'
Search Results
2. Chiral multiferroicity in two-dimensional hybrid organic-inorganic perovskites.
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Zheng H, Ghosh A, Swamynadhan MJ, Zhang Q, Wong WPD, Wu Z, Zhang R, Chen J, Cimpoesu F, Ghosh S, Campbell BJ, Wang K, Stroppa A, Mahendiran R, and Loh KP
- Abstract
Chiral multiferroics offer remarkable capabilities for controlling quantum devices at multiple levels. However, these materials are rare due to the competing requirements of long-range orders and strict symmetry constraints. In this study, we present experimental evidence that the coexistence of ferroelectric, magnetic orders, and crystallographic chirality is achievable in hybrid organic-inorganic perovskites [(R/S)-β-methylphenethylamine]
2 CuCl4 . By employing Landau symmetry mode analysis, we investigate the interplay between chirality and ferroic orders and propose a novel mechanism for chirality transfer in hybrid systems. This mechanism involves the coupling of non-chiral distortions, characterized by defining a pseudo-scalar quantity, ξ = p ⋅ r ( p represents the ferroelectric displacement vector and r denotes the ferro-rotational vector), which distinguishes between (R)- and (S)-chirality based on its sign. Moreover, the reversal of this descriptor's sign can be associated with coordinated transitions in ferroelectric distortions, Jahn-Teller antiferro-distortions, and Dzyaloshinskii-Moriya vectors, indicating the mediating role of crystallographic chirality in magnetoelectric correlations., (© 2024. The Author(s).)- Published
- 2024
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3. Computational Screening and Stabilization of Boron-Substituted Type-I and Type-II Carbon Clathrates.
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Bi T, Eggers BT, Cohen RE, Campbell BJ, and Strobel T
- Abstract
Boron substitution represents a promising approach to stabilize carbon clathrate structures, but no thermodynamically stable substitution schemes have been identified for frameworks other than the type-VII (sodalite) structure type. To investigate the possibility for additional tetrahedral carbon-based clathrate networks, more than 5000 unique boron decoration schemes were investigated computationally for type-I and type-II carbon clathrates with a range of guest elements including Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba. Density functional theory calculations were performed at 10 and 50 GPa, and the stability and impact of boron substitution were evaluated. The results indicate that the boron-substituted carbon clathrates are stabilized under high-pressure conditions. Full cage occupancies of intermediate-sized guest atoms (e.g., Na, Ca, and Sr) are the most favorable energetically. Clathrate stability is maximized when the boron atoms are substituted within the hexagonal rings of the large [5
12 62 ]/[512 64 ] cages. Several structures with favorable formation enthalpies <-200 meV/atom were predicted, and type-I Ca8 B16 C30 is on the convex hull at 50 GPa. This structure represents the first thermodynamically stable type-I clathrate identified and suggests that boron-substituted carbon clathrates may represent a large family of diamond-like framework materials with a range of structure types and guest/framework substitutions.- Published
- 2024
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4. Electron Spin Decoherence Dynamics in Magnetic Manganese Hybrid Organic-Inorganic Crystals: The Effect of Lattice Dimensionality.
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Zheng H, Ghosh A, Swamynadhan MJ, Wang G, Zhang Q, Wu X, Abdelwahab I, Wong WPD, Xu QH, Ghosh S, Chen J, Campbell BJ, Stroppa A, Lin J, Mahendiran R, and Loh KP
- Abstract
Organic-inorganic metal hybrids with their tailorable lattice dimensionality and intrinsic spin-splitting properties are interesting material platforms for spintronic applications. While the spin decoherence process is extensively studied in lead- and tin-based hybrids, these systems generally show short spin decoherence lifetimes, and their correlation with the lattice framework is still not well-understood. Herein, we synthesized magnetic manganese hybrid single crystals of (4-fluorobenzylamine)
2 MnCl4 , (( R )-3-fluoropyrrolidinium)MnCl3 , and (pyrrolidinium)2 MnCl4 , which represent a change in lattice dimensionality from 2D and 1D to 0D, and studied their spin decoherence processes using continuous-wave electron spin resonance spectroscopy. All manganese hybrids exhibit nanosecond-scale spin decoherence time τ2 dominated by the symmetry-directed spin exchange interaction strengths of Mn2+ -Mn2+ pairs, which is much longer than lead- and tin-based metal hybrids. In contrast to the similar temperature variation laws of τ2 in 2D and 0D structures, which first increase and gradually drop afterward, the 1D structure presents a monotonous rise of τ2 with the temperatures, indicating the strong correlation of spin decoherence with the lattice rigidity of the inorganic framework. This is also rationalized on the basis that the spin decoherence is governed by the competitive contributions from motional narrowing (prolonging the τ2 ) and electron-phonon coupling interaction (shortening the τ2 ), both of which are thermally activated, with the difference that the former is more pronounced in rigid crystalline lattices.- Published
- 2023
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5. Gut bacteria of adult and larval Cotinis nitida Linnaeus (Coleoptera: Scarabaeidae) demonstrate community differences according to respective life stage and gut region.
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Kucuk RA, Campbell BJ, Lyon NJ, Shelby EA, and Caterino MS
- Abstract
The close association between bacteria and insect hosts has played an indispensable role in insect diversity and ecology. Thus, continued characterization of such insect-associated-microbial communities is imperative, especially those of saprophagous scarab beetles. The bacterial community of the digestive tract of adults and larvae of the cetoniine scarab species Cotinis nitida is characterized according to life stage, gut structure, and sex via high-throughput 16S rRNA gene amplicon sequencing. Through permutational ANOVAs of the resulting sequences, bacterial communities of the digestive system are shown to differ significantly between adults and larvae in taxon richness, evenness and relatedness. Significant bacterial community-level differences are also observed between the midgut and hindgut in adult beetles, while no significant host-sex differences are observed. The partitioning between bacterial communities in the larval digestive system is shown through significant differences in two distinct hindgut regions, the ileum and the expanded paunch, but not between the midgut and ileum portion of the hindgut region. These data further corroborate the hypothesis of strong community partitioning in the gut of members of the Scarabaeoidea, suggest hypotheses of physiological-digestive association, and also demonstrate the presence of a seemingly unusual non-scarab-associated taxon. These findings contribute to a general portrait of scarabaeoid digestive tract bacterial communities while illuminating the microbiome of a common new world cetoniine of the Gymnetini-a tribe largely neglected in scarab and beetle microbiome and symbiosis literature., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kucuk, Campbell, Lyon, Shelby and Caterino.)
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- 2023
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6. Effect of Probiotics in Breast Cancer: A Systematic Review and Meta-Analysis.
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Thu MS, Ondee T, Nopsopon T, Farzana IAK, Fothergill JL, Hirankarn N, Campbell BJ, and Pongpirul K
- Abstract
Probiotics may have the potential to protect against breast cancer, partly through systemic immunomodulatory action and active impact upon intestinal microbiota. Given a few clinical studies on their curative role, we conducted a systematic review of the potential effects of probiotics in breast cancer patients and survivors of breast cancer, aiming to support further clinical studies. A literature search was performed using PubMed, Embase, and the CENTRAL databases from inception through to March 2022. A total of eight randomized clinical trials were identified from thirteen articles published between 2004 and 2022. We evaluated quality-of-life measures, observed bacterial species and diversity indices, probiotic-related metabolites, inflammatory biomarkers, and other responses in breast cancer patients and survivors. Results were synthesized qualitatively and quantitatively using random-effects meta-analysis. Different probiotics supplements utilized included Lactobacillus species alone (Lacto), with or without estriol; probiotic combinations of Lactobacillus with Bifidobacterium (ProLB), with or without prebiotic fructooligosaccharides (FOS); ProLB plus Streptococcus and FOS (ProLBS + FOS); and ProLB plus Enterococcus (ProLBE). We found that use of ProLBS with FOS in breast cancer patients and use of ProLBE in survivors of breast cancer show potential benefits in countering obesity and dyslipidemia. ProLBS with FOS use decreases pro-inflammatory TNF-α in breast cancer survivors and improves quality of life in those with breast-cancer-associated lymphedema. Supplementing probiotics capsules (10
9 CFU) with a prebiotic and using an intake duration of 10 weeks could provide a better approach than probiotics alone., Competing Interests: The authors declare no conflict of interest.- Published
- 2023
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7. Interleukin-10 Deficiency Impacts on TNF-Induced NFκB Regulated Responses In Vivo.
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Papoutsopoulou S, Pollock L, Williams JM, Abdul-Mahdi MMLF, Dobbash R, Duckworth CA, and Campbell BJ
- Abstract
Interleukin-10 (IL-10) is an anti-inflammatory cytokine that has a major protective role against intestinal inflammation. We recently revealed that intestinal epithelial cells in vitro regulate NFκB-driven transcriptional responses to TNF via an autocrine mechanism dependent on IL-10 secretion. Here in this study, we investigated the impact of IL-10 deficiency on the NFκB pathway and its downstream targets in the small intestinal mucosa in vivo. We observed dysregulation of TNF, IκBα, and A20 gene and protein expression in the small intestine of steady-state or TNF-injected Il10
-/- mice, compared to wild-type C57BL6/J counterparts. Upon TNF injection, tissue from the small intestine showed upregulation of NFκB p65[RelA] activity, which was totally diminished in Il10-/- mice and correlated with reduced levels of TNF, IκBα, and A20 expression. In serum, whilst IgA levels were noted to be markedly downregulated in IL-10-deficient- mice, normal levels of mucosal IgA were seen in intestine mucosa. Importantly, dysregulated cytokine/chemokine levels were observed in both serum and intestinal tissue lysates from naïve, as well as TNF-injected Il10-/- mice. These data further support the importance of the IL-10-canonical NFκB signaling pathway axis in regulating intestinal mucosa homeostasis and response to inflammatory triggers in vivo.- Published
- 2022
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8. Cross-inoculation of rhizobiome from a congeneric ruderal plant imparts drought tolerance in maize (Zea mays) through changes in root morphology and proteome.
- Author
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Zhang Z, Jatana BS, Campbell BJ, Gill J, Suseela V, and Tharayil N
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- Crops, Agricultural metabolism, Endoplasmic Reticulum-Associated Degradation, Proteome metabolism, Stress, Physiological, Droughts, Zea mays metabolism
- Abstract
Rhizobiome confer stress tolerance to ruderal plants, yet their ability to alleviate stress in crops is widely debated, and the associated mechanisms are poorly understood. We monitored the drought tolerance of maize (Zea mays) as influenced by the cross-inoculation of rhizobiota from a congeneric ruderal grass Andropogon virginicus (andropogon-inoculum), and rhizobiota from organic farm maintained under mesic condition (organic-inoculum). Across drought treatments (40% field capacity), maize that received andropogon-inoculum produced two-fold greater biomass. This drought tolerance translated to a similar leaf metabolomic composition as that of the well-watered control (80% field capacity) and reduced oxidative damage, despite a lower activity of antioxidant enzymes. At a morphological-level, drought tolerance was associated with an increase in specific root length and surface area facilitated by the homeostasis of phytohormones promoting root branching. At a proteome-level, the drought tolerance was associated with upregulation of proteins related to glutathione metabolism and endoplasmic reticulum-associated degradation process. Fungal taxa belonging to Ascomycota, Mortierellomycota, Archaeorhizomycetes, Dothideomycetes, and Agaricomycetes in andropogon-inoculum were identified as potential indicators of drought tolerance. Our study provides a mechanistic understanding of the rhizobiome-facilitated drought tolerance and demonstrates a better path to utilize plant-rhizobiome associations to enhance drought tolerance in crops., (© 2022 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)
- Published
- 2022
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9. Enumeration and tabulation of magnetic (3+d)-dimensional superspace groups.
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Stokes HT and Campbell BJ
- Abstract
A magnetic superspace group (MSSG) simultaneously constrains both the magnetic and non-magnetic (e.g. displacive, occupational, rotation and strain) degrees of freedom of an incommensurately modulated magnetic crystal. We present the first enumeration and tabulation of all non-equivalent (3+d)-dimensional magnetic superspace groups for d = 1, 2 and 3 independent incommensurate modulations, along with a number, symbol and reference setting for each group. We explain the process for generating an exhaustive set of inequivalent magnetic superspace groups, describe several examples, and show how the tables can be accessed via the ISO(3+d)D interface within the ISOTROPY Software Suite. We recommend that published incommensurate magnetic structures indicate a magnetic superspace-group number and symbol from these tables, as well as the transformation matrix from the published group setting to the reference setting used in these tables.
- Published
- 2022
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10. Root metabolome of plant-arbuscular mycorrhizal symbiosis mirrors the mutualistic or parasitic mycorrhizal phenotype.
- Author
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Kaur S, Campbell BJ, and Suseela V
- Subjects
- Metabolome, Phenotype, Plant Roots physiology, Symbiosis, Mycorrhizae physiology
- Abstract
The symbiosis of arbuscular mycorrhizal fungi (AMF) with plants, the most ancient and widespread association, exhibits phenotypes that range from mutualism to parasitism. However, we still lack an understanding of the cellular-level mechanisms that differentiate and regulate these phenotypes. We assessed the modulation in growth parameters and root metabolome of two sorghum accessions inoculated with two AMF species (Rhizophagus irregularis, Gigaspora gigantea), alone and in a mixture under phosphorus (P) limiting conditions. Rhizophagus irregularis exhibited a mutualistic phenotype with increased P uptake and plant growth. This positive outcome was associated with a facilitatory metabolic response including higher abundance of organic acids and specialized metabolites critical to maintaining a functional symbiosis. However, G. gigantea exhibited a parasitic phenotype that led to plant growth depression and resulted in inhibitory plant metabolic responses including the higher abundance of p-hydroxyphenylacetaldoxime with antifungal properties. These findings suggest that the differential outcome of plant-AMF symbiosis could be regulated by or reflected in changes in the root metabolome that arises from the interaction of the plant species with the specific AMF species. A mutualistic symbiotic association prevailed when the host plants were exposed to a mixture of AMF. Our results provide a metabolome-level landscape of plant-AMF symbiosis and highlight the importance of the identity of both AMF and crop genotypes in facilitating a mutualistic AMF symbiosis., (© 2022 The Authors. New Phytologist © 2022 New Phytologist Foundation.)
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- 2022
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11. Effects of Human RelA Transgene on Murine Macrophage Inflammatory Responses.
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Papoutsopoulou S, Morris L, Bayliff A, Mair T, England H, Stagi M, Bergey F, Alam MT, Sheibani-Tezerji R, Rosenstiel P, Müller W, Martins Dos Santos VAP, and Campbell BJ
- Abstract
The NFκB transcription factors are major regulators of innate immune responses, and NFκB signal pathway dysregulation is linked to inflammatory disease. Here, we utilised bone marrow-derived macrophages from the p65-DsRedxp/IκBα-eGFP transgenic strain to study the functional implication of xenogeneic (human) RelA(p65) protein introduced into the mouse genome. Confocal imaging showed that human RelA is expressed in the cells and can translocate to the nucleus following activation of Toll-like receptor 4. RNA sequencing of lipid A-stimulated macrophages, revealed that human RelA impacts on murine gene transcription, affecting both non-NFκB and NFκB target genes, including immediate-early and late response genes, e.g., Fos and Cxcl10 . Validation experiments on NFκB targets revealed markedly reduced mRNA levels, but similar kinetic profiles in transgenic cells compared to wild-type. Enrichment pathway analysis of differentially expressed genes revealed interferon and cytokine signaling were affected. These immune response pathways were also affected in macrophages treated with tumor necrosis factor. Data suggests that the presence of xenogeneic RelA protein likely has inhibitory activity, altering specific transcriptional profiles of key molecules involved in immune responses. It is therefore essential that this information be taken into consideration when designing and interpreting future experiments using this transgenic strain.
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- 2022
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12. Introducing a unified magnetic space-group symbol.
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Campbell BJ, Stokes HT, Perez-Mato JM, and Rodríguez-Carvajal J
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- Magnetic Phenomena
- Abstract
The two commonly used systems of magnetic space-group (MSG) symbols, with accompanying numbers and settings, are those of Belov-Neronova-Smirnova (BNS) and Opechowski-Guccione (OG). The symbols from both systems have been used for several decades now. Both have advantages and disadvantages. Both present challenges of interpretation to novice and expert users alike, which can inhibit understanding and lead to errors in published magnetic structures. To address each of these challenges going forward, a new unified (UNI) MSG symbol is introduced, which combines a modified BNS symbol with essential information from the OG symbol.
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- 2022
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13. Soluble Non-Starch Polysaccharides From Plantain ( Musa x paradisiaca L.) Diminish Epithelial Impact of Clostridioides difficile .
- Author
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Simpson HL, Roberts CL, Thompson LM, Leiper CR, Gittens N, Trotter E, Duckworth CA, Papoutsopoulou S, Miyajima F, Roberts P, O'Kennedy N, Rhodes JM, and Campbell BJ
- Abstract
Clostridioides difficile infection (CDI) is a leading cause of antibiotic-associated diarrhoea. Adhesion of this Gram-positive pathogen to the intestinal epithelium is a crucial step in CDI, with recurrence and relapse of disease dependent on epithelial interaction of its endospores. Close proximity, or adhesion of, hypervirulent strains to the intestinal mucosa are also likely to be necessary for the release of C. difficile toxins, which when internalized, result in intestinal epithelial cell rounding, damage, inflammation, loss of barrier function and diarrhoea. Interrupting these C. difficile -epithelium interactions could therefore represent a promising therapeutic strategy to prevent and treat CDI. Intake of dietary fibre is widely recognised as being beneficial for intestinal health, and we have previously shown that soluble non-starch polysaccharides (NSP) from plantain banana ( Musa spp.), can block epithelial adhesion and invasion of a number of gut pathogens, such as E. coli and Salmonellae. Here, we assessed the action of plantain NSP, and a range of alternative soluble plant fibres, for inhibitory action on epithelial interactions of C. difficile clinical isolates, purified endospore preparations and toxins. We found that plantain NSP possessed ability to disrupt epithelial adhesion of C. difficile vegetative cells and spores, with inhibitory activity against C. difficile found within the acidic (pectin-rich) polysaccharide component, through interaction with the intestinal epithelium. Similar activity was found with NSP purified from broccoli and leek, although seen to be less potent than NSP from plantain. Whilst plantain NSP could not block the interaction and intracellular action of purified C. difficile toxins, it significantly diminished the epithelial impact of C. difficile , reducing both bacteria and toxin induced inflammation, activation of caspase 3/7 and cytotoxicity in human intestinal cell-line and murine intestinal organoid cultures. Dietary supplementation with soluble NSP from plantain may therefore confer a protective effect in CDI patients by preventing adhesion of C. difficile to the mucosa, i.e. a "contrabiotic" effect, and diminishing its epithelial impact. This suggests that plantain soluble dietary fibre may be a therapeutically effective nutritional product for use in the prevention or treatment of CDI and antibiotic-associated diarrhoea., Competing Interests: NO’K is a present, and CR a past, employee of Provexis Plc. BC, HS and JR received additional funding support from the biotech partner Provexis Plc as part of the BBSRC Industrial CASE studentship (BB/I016783/1). JR is listed as inventor on patents held by Provexis Plc, in a licence agreement with the University of Liverpool, for use of complex oligosaccharides in the prevention or treatment of inflammatory bowel disease (US8945639B2), and for use of soluble fibres in antibiotic-associated diarrhoea (US20120165289A1). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Simpson, Roberts, Thompson, Leiper, Gittens, Trotter, Duckworth, Papoutsopoulou, Miyajima, Roberts, O’Kennedy, Rhodes and Campbell.)
- Published
- 2021
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14. The ISOTILT software for discovering cooperative rigid-unit rotations in networks of interconnected rigid units.
- Author
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Campbell BJ, Stokes HT, Averett TB, Machlus S, and Yost CJ
- Abstract
A user-friendly web-based software tool called ' ISOTILT ' is introduced for detecting cooperative rigid-unit modes (RUMs) in networks of interconnected rigid units ( e.g. molecules, clusters or polyhedral units). This tool implements a recently described algorithm in which symmetry-mode patterns of pivot-atom rotation and displacement vectors are used to construct a linear system of equations whose null space consists entirely of RUMs. The symmetry modes are first separated into independent symmetry-mode blocks and the set of equations for each block is solved separately by singular value decomposition. ISOTILT is the newest member of the ISOTROPY Software Suite . Here, it is shown how to prepare structural and symmetry-mode information for use in ISOTILT , how to use each of ISOTILT 's input fields and options, and how to use and interpret ISOTILT output., (© Branton J. Campbell et al. 2021.)
- Published
- 2021
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15. Quantitative trait loci controlling agronomic and biochemical traits in Cannabis sativa.
- Author
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Woods P, Campbell BJ, Nicodemus TJ, Cahoon EB, Mullen JL, and McKay JK
- Subjects
- Cannabis growth & development, Cannabis metabolism, Intramolecular Transferases genetics, Plant Proteins genetics, Quantitative Trait, Heritable, Cannabis genetics, Quantitative Trait Loci
- Abstract
Understanding the genetic basis of complex traits is a fundamental goal of evolutionary genetics. Yet, the genetics controlling complex traits in many important species such as hemp (Cannabis sativa) remain poorly investigated. Because hemp's change in legal status with the 2014 and 2018 U.S. Federal Farm Bills, interest in the genetics controlling its numerous agriculturally important traits has steadily increased. To better understand the genetics of agriculturally important traits in hemp, we developed an F2 population by crossing two phenotypically distinct hemp cultivars (Carmagnola and USO31). Using whole-genome sequencing, we mapped quantitative trait loci (QTL) associated with variation in numerous agronomic and biochemical traits. A total of 69 loci associated with agronomic (34) and biochemical (35) trait variation were identified. We found that most QTL co-localized, suggesting that the phenotypic distinctions between Carmagnola and USO31 are largely controlled by a small number of loci. We identified TINY and olivetol synthase as candidate genes underlying co-localized QTL clusters for agronomic and biochemical traits, respectively. We functionally validated the olivetol synthase candidate by expressing the alleles in yeast. Gas chromatography-mass spectrometry assays of extracts from these yeast colonies suggest that the USO31 olivetol synthase is functionally less active and potentially explains why USO31 produces lower cannabinoids compared to Carmagnola. Overall, our results help modernize the genomic understanding of complex traits in hemp., (© The Author(s) 2021. Published by Oxford University Press on behalf of Genetics Society of America.)
- Published
- 2021
- Full Text
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