Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2024
Forfattere
Jorunn Elisabeth Olsen Paul Grini Igor A. Yakovlev Marcos Viejo Mari Talgø Syvertsen Payel Bhattacharjee Mallikarjuna Rao Kovi Torstein Tengs Yupeng Zhang Carl Gunnar FossdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Xia Wang Dawei Chen Mengnan Guo Yao Ning Mingze Geng Jing Guo Jiahui Gao Dong Zhao Yupeng Zhang Qianpeng Li Lixiang Li Shiyang Li Yanqing Li Xiaoran Xie Xiuli Zuo Jingxin LiSammendrag
Colon cancer is increasing worldwide and is commonly regarded as hormone independent, yet recent reports have implicated sex hormones in its development. Nevertheless, the role of hormones from the hypothalamus–hypophysis axis in colitis-associated colorectal cancer (CAC) remains uncertain. In this study, we observed a significant reduction in the expression of the oxytocin receptor (OXTR) in colon samples from both patient with colitis and patient with CAC. To investigate further, we generated mice with an intestinal-epithelium-cell-specific knockout of OXTR. These mice exhibited markedly increased susceptibility to dextran-sulfate-sodium-induced colitis and dextran sulfate sodium/azoxymethane-induced CAC compared to wild-type mice. Our findings indicate that OXTR depletion impaired the inner mucus of the colon epithelium. Mechanistically, oxytocin was found to regulate Mucin 2 maturation through β1-3-N-acetylglucosaminyltransferase 7 (B3GNT7)-mediated fucosylation. Interestingly, we observed a positive correlation between B3GNT7 expression and OXTR expression in human colitis and CAC colon samples. Moreover, the simultaneous activations of OXTR and fucosylation by l-fucose significantly alleviated tumor burden. Hence, our study unveils oxytocin’s promising potential as an affordable and effective therapeutic intervention for individuals affected by colitis and CAC.
Forfattere
Ingrid Schafroth Sandbakken Hang Su Louise Johansen Yupeng Zhang Einar Ringø Randi Røsbak Igor A. Yakovlev Kathrine Kjos Five Rolf-Erik OlsenSammendrag
The feed legislation allows the use of fish protein hydrolysates in feed for the same species in which it came from, since enzymatic hydrolysis degrades the proteins and eliminates potential prions, which have caused disease in mammals, but not in fish. In this trial, we investigated the effects of partially replacing dietary fishmeal (FM) with salmon protein hydrolysate (FPH) on the intestinal gene expression and microbiota. Atlantic salmon post smolts were either fed a control diet containing 30% fishmeal (FM), a 20% FM diet with 9% salmon hydrolysate (FPH-09) or a 10% FM diet with 18% salmon hydrolysate (FPH-18), until doubling of weight. Gene expression analysis by RNA sequencing of pyloric caeca (PC), midgut (MG) and hindgut (HG) revealed a downregulation of immunological genes involved in inflammation in the intestine of FPH-18 fed salmon compared to salmon fed the FM control. The gene expression of paralogous peptide transporters (PepT) was analyzed by real time quantitative PCR in PC, anterior midgut (AMG), posterior midgut (PMG) and HG of salmon fed all the three diets. The PepT1b paralog had highest relative expression levels in PC and AMG, suggesting that PepT1b is most important for peptide uptake in the anterior intestine. PepT1a was also mainly expressed in the PC and AMG, but at lower levels than PepT1b and PepT2b in the AMG. The PepT2b paralog had high levels of expression in AMG, PMG and HG indicating that it contributed significantly to peptide uptake in the posterior part of the gastrointestinal tract. The gut microbiota in the mucosa and digesta of the MG and HG, were dominated by the phyla Cyanobacteria and Proteobacteria, but also Firmicutes were present. The only dietary effect on the microbiota was the higher prevalence of the phyla Spirochaetes in the mucosa of FPH-18 fed salmon compared to the FM fed salmon. In conclusion, replacing FM with salmon hydrolysate reduced the expression of inflammatory markers in the Atlantic salmon intestine suggesting improved health benefits. The reduced inflammation may be related to the reduced FM content, potentially bioactive peptides in the hydrolysate and/or the altered gut microbial composition.
2023
Forfattere
Carl Gunnar Fossdal Igor A. Yakovlev Marcos Viejo Paul Grini Paal Krokene Yupeng Zhang Jorunn Elisabeth OlsenSammendrag
Det er ikke registrert sammendrag
Forfattere
Yupeng Zhang Marcos Viejo Igor A. Yakovlev Torstein Tengs Paal Krokene Timo Hytönen Paul Grini Carl Gunnar FossdalSammendrag
A major challenge for plants in a rapidly changing climate is to adapt to rising temperatures. Some plants adapt to temperature conditions by generating an epigenetic memory that can be transmitted both meiotically and mitotically. Such epigenetic memories may increase phenotypic variation to global warming and provide time for adaptation to occur through classical genetic selection. The goal of this study was to understand how warmer temperature conditions experienced during sexual and asexual reproduction affect the transcriptomes of different strawberry (Fragaria vesca) ecotypes. We let four European F. vesca ecotypes reproduce at two contrasting temperatures (18 and 28°C), either asexually through stolon formation for several generations, or sexually by seeds (achenes). We then analyzed the transcriptome of unfolding leaves, with emphasis on differential expression of genes belonging to the epigenetic machinery. For asexually reproduced plants we found a general transcriptomic response to temperature conditions but for sexually reproduced plants we found less significant responses. We predicted several splicing isoforms for important genes (e.g. a SOC1, LHY, and SVP homolog), and found significantly more differentially presented splicing event variants following asexual vs. sexual reproduction. This difference could be due to the stochastic character of recombination during meiosis or to differential creation or erasure of epigenetic marks during embryogenesis and seed development. Strikingly, very few differentially expressed genes were shared between ecotypes, perhaps because ecotypes differ greatly both genetically and epigenetically. Genes related to the epigenetic machinery were predominantly upregulated at 28°C during asexual reproduction but downregulated after sexual reproduction, indicating that temperature-induced change affects the epigenetic machinery differently during the two types of reproduction.
Forfattere
Yupeng Zhang Tuomas Toivainen Kathryn Mackenzie Igor A. Yakovlev Paal Krokene Timo Hytönen Paul Grini Carl Gunnar FossdalSammendrag
Temperature conditions experienced during embryogenesis and seed development may induce epigenetic changes that increase phenotypic variation in plants. Here we investigate if embryogenesis and seed development at two different temperatures (28 vs. 18°C) result in lasting phenotypic effects and DNA methylation changes in woodland strawberry (Fragaria vesca). Using five European ecotypes from Spain (ES12), Iceland (ICE2), Italy (IT4), and Norway (NOR2 and NOR29), we found statistically significant differences between plants from seeds produced at 18 or 28°C in three of four phenotypic features investigated under common garden conditions. This indicates the establishment of a temperature-induced epigenetic memory-like response during embryogenesis and seed development. The memory effect was significant in two ecotypes: in NOR2 flowering time, number of growth points and petiole length were affected, and in ES12 number of growth points was affected. This indicates that genetic differences between ecotypes in their epigenetic machinery, or other allelic differences, impact this type of plasticity. We observed statistically significant differences between ecotypes in DNA methylation marks in repetitive elements, pseudogenes, and genic elements. Leaf transcriptomes were also affected by embryonic temperature in an ecotype-specific manner. Although we observed significant and lasting phenotypic change in at least some ecotypes, there was considerable variation in DNA methylation between individual plants within each temperature treatment. This within-treatment variability in DNA methylation marks in F. vesca progeny may partly be a result of allelic redistribution from recombination during meiosis and subsequent epigenetic reprogramming during embryogenesis.
Forfattere
Yupeng Zhang Guangxun Fan Tuomas Toivainen Torstein Tengs Igor A. Yakovlev Paal Krokene Timo Hytönen Carl Gunnar Fossdal Paul GriniSammendrag
Plants must adapt with increasing speed to global warming to maintain their fitness. One rapid adaptation mechanism is epigenetic memory, which may provide organisms sufficient time to adapt to climate change. We studied how the perennial Fragaria vesca adapted to warmer temperatures (28°C vs. 18°C) over three asexual generations. Differences in flowering time, stolon number, and petiole length were induced by warmer temperature in one or more ecotypes after three asexual generations and persisted in a common garden environment. Induced methylome changes differed between the four ecotypes from Norway, Iceland, Italy, and Spain, but shared methylome responses were also identified. Most differentially methylated regions (DMRs) occurred in the CHG context, and most CHG and CHH DMRs were hypermethylated at the warmer temperature. In eight CHG DMR peaks, a highly similar methylation pattern could be observed between ecotypes. On average, 13% of the differentially methylated genes between ecotypes also showed a temperature-induced change in gene expression. We observed ecotype-specific methylation and expression patterns for genes related to gibberellin metabolism, flowering time, and epigenetic mechanisms. Furthermore, we observed a negative correlation with gene expression when repetitive elements were found near (±2 kb) or inside genes. In conclusion, lasting phenotypic changes indicative of an epigenetic memory were induced by warmer temperature and were accompanied by changes in DNA methylation patterns. Both shared methylation patterns and transcriptome differences between F. vesca accessions were observed, indicating that DNA methylation may be involved in both general and ecotype-specific phenotypic variation.
2022
Forfattere
Yupeng Zhang Guangxun Fan Tuomas Toivenen Torstein Tengs Igor A. Yakovlev Javier Andrés Paal Krokene Timo Hytönen Paul Grini Carl Gunnar FossdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Panpan Feng Dawei Chen Xia Wang Yanxia Li Zhenyu Li Boya Li Yupeng Zhang Wei Li Jingru Zhang Jingjing Ye Baobing Zhao Jingxin Li Chunyan JiSammendrag
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignant leukemia with extremely limited treatment for relapsed patients. N6‐methyladenosine (m6A) reader insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) participates in the initiation and growth of cancers by communicating with various targets. Here, we found IGF2BP2 was highly expressed in T-ALL. Gain and loss of IGF2BP2 demonstrated IGF2BP2 was essential for T-ALL cell proliferation in vitro and loss of IGF2BP2 prolonged animal survival in a human T-ALL xenograft model. Mechanistically, IGF2BP2 directly bound to T-ALL oncogene NOTCH1 via an m6A dependent manner. Furthermore, we identified a small-molecule IGF2BP2 inhibitor JX5 and treatment of T-ALL with JX5 showed similar functions as knockdown of IGF2BP2. These findings not only shed light on the role of IGF2BP2 in T-ALL, but also provide an alternative γ‑Secretase inhibitors (GSI) therapy to treat T-ALL.
Forfattere
Raghuram Badmi Torstein Tengs May Bente Brurberg Abdelhameed Elameen Yupeng Zhang Lisa Karine Haugland Carl Gunnar Fossdal Timo Hytönen Paal Krokene Tage ThorstensenSammendrag
Grey mold caused by the necrotrophic fungal pathogen Botrytis cinerea can affect leaves, flowers, and berries of strawberry, causing severe pre- and postharvest damage. The defense elicitor β-aminobutyric acid (BABA) is reported to induce resistance against B. cinerea and many other pathogens in several crop plants. Surprisingly, BABA soil drench of woodland strawberry (Fragaria vesca) plants two days before B. cinerea inoculation caused increased infection in leaf tissues, suggesting that BABA induce systemic susceptibility in F. vesca. To understand the molecular mechanisms involved in B. cinerea susceptibility in leaves of F. vesca plants soil drenched with BABA, we used RNA sequencing to characterize the transcriptional reprogramming 24 h post-inoculation. The number of differentially expressed genes (DEGs) in infected vs. uninfected leaf tissue in BABA-treated plants was 5205 (2237 upregulated and 2968 downregulated). Upregulated genes were involved in pathogen recognition, defense response signaling, and biosynthesis of secondary metabolites (terpenoid and phenylpropanoid pathways), while downregulated genes were involved in photosynthesis and response to auxin. In control plants not treated with BABA, we found a total of 5300 DEGs (2461 upregulated and 2839 downregulated) after infection. Most of these corresponded to those in infected leaves of BABA-treated plants but a small subset of DEGs, including genes involved in ‘response to biologic stimulus‘, ‘photosynthesis‘ and ‘chlorophyll biosynthesis and metabolism’, differed significantly between treatments and could play a role in the induced susceptibility of BABA-treated plants.