| 1. |
- Faraz, Mahmood, et al.
(författare)
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LRIG1 gene copy number analysis by ddPCR and correlations to clinical factors in breast cancer
- 2020
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Ingår i: BMC Cancer. - : BioMed Central. - 1471-2407. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) copy number alterations and unbalanced gene recombination events have been reported to occur in breast cancer. Importantly, LRIG1 loss was recently shown to predict early and late relapse in stage I-II breast cancer.Methods: We developed droplet digital PCR (ddPCR) assays for the determination of relative LRIG1 copy numbers and used these assays to analyze LRIG1 in twelve healthy individuals, 34 breast tumor samples previously analyzed by fluorescence in situ hybridization (FISH), and 423 breast tumor cytosols.Results: Four of the LRIG1/reference gene assays were found to be precise and robust, showing copy number ratios close to 1 (mean, 0.984; standard deviation, +/-0.031) among the healthy control population. The correlation between the ddPCR assays and previous FISH results was low, possibly because of the different normalization strategies used. One in 34 breast tumors (2.9%) showed an unbalanced LRIG1 recombination event. LRIG1 copy number ratios were associated with the breast cancer subtype, steroid receptor status, ERBB2 status, tumor grade, and nodal status. Both LRIG1 loss and gain were associated with unfavorable metastasis-free survival; however, they did not remain significant prognostic factors after adjustment for common risk factors in the Cox regression analysis. Furthermore, LRIG1 loss was not significantly associated with survival in stage I and II cases.Conclusions: Although LRIG1 gene aberrations may be important determinants of breast cancer biology, and prognostic markers, the results of this study do not verify an important role for LRIG1 copy number analyses in predicting the risk of relapse in early-stage breast cancer.
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| 2. |
- Frith, Martin C., et al.
(författare)
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Pseudo-messenger RNA : Phantoms of the transcriptome
- 2006
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Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 2:4, s. 504-514
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Tidskriftsartikel (refereegranskat)abstract
- The mammalian transcriptome harbours shadowy entities that resist classification and analysis. In analogy with pseudogenes, we define pseudo-messenger RNA to be RNA molecules that resemble protein- coding mRNA, but cannot encode full-length proteins owing to disruptions of the reading frame. Using a rigorous computational pipeline, which rules out sequencing errors, we identify 10,679 pseudo - messenger RNAs ( approximately half of which are transposonassociated) among the 102,801 FANTOM3 mouse cDNAs: just over 10% of the FANTOM3 transcriptome. These comprise not only transcribed pseudogenes, but also disrupted splice variants of otherwise protein- coding genes. Some may encode truncated proteins, only a minority of which appear subject to nonsense- mediated decay. The presence of an excess of transcripts whose only disruptions are opal stop codons suggests that there are more selenoproteins than currently estimated. We also describe compensatory frameshifts, where a segment of the gene has changed frame but remains translatable. In summary, we survey a large class of non- standard but potentially functional transcripts that are likely to encode genetic information and effect biological processes in novel ways. Many of these transcripts do not correspond cleanly to any identifiable object in the genome, implying fundamental limits to the goal of annotating all functional elements at the genome sequence level.
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| 3. |
- Huminiecki, Lukasz, et al.
(författare)
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2R and remodeling of vertebrate signal transduction engine
- 2010
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Ingår i: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 8, s. 146-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Whole genome duplication (WGD) is a special case of gene duplication, observed rarely in animals, where all genes duplicate simultaneously through polyploidisation. Two rounds of WGD (2R-WGD) occurred at the base of vertebrates, giving rise to an enormous wave of genetic novelty, but a systematic analysis of functional consequences of this event has not yet been performed. Results: We show that 2R-WGD affected overwhelming majority (74%) of signaling genes, in particular developmental pathways involving receptor tyrosine kinases, Wnt and TGF-beta ligands, GPCRs, and the apoptosis pathway. 2R-retained genes, in contrast to tandem duplicates, were enriched in protein interaction domains, and multifunctional signaling modules of Ras and MAP-kinase cascades. 2R-WGD had a fundamental impact on the cell-cycle machinery; redefined molecular building blocks of the neuronal synapse; and was formative for vertebrate brains. We investigated 2R-associated nodes in context of the human signaling network, as well as an inferred ancestral pre-2R (AP2R) network, and found that hubs (particularly involving negative regulations), were preferentially retained, with high-connectivity driving retention. Finally, microarrays and proteomics demonstrated a trend for gradual paralog expression divergence, independent of the duplication mechanism; but inferred ancestral expression states suggested preferential sub-functionalisation among 2R-ohnologs (2ROs). Conclusions: The 2R event left an indelible imprint on vertebrate signaling and cell-cycle. We show that 2R-WGD preferentially retained genes are associated with higher organismal complexity (e.g. locomotion, nervous system, morphogenesis), while genes associated with basic cellular functions (e.g. translation, replication, splicing, recombination; with the notable exception of cell-cycle) tended to be excluded. 2R-WGD set the stage for the emergence of key vertebrate functional novelties (such as complex brains, circulatory system, heart, bone, cartilage, musculature, and the adipose tissue). Full explanation of the impact of 2R on evolution, function, and the flow of information in vertebrate signaling networks is likely to have practical consequences for regenerative medicine, stem cell therapies, and cancer treatment.
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| 4. |
- Huminiecki, Lukasz, et al.
(författare)
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Emergence, development and diversification of the TGF-beta signalling pathway within the animal kingdom
- 2009
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Ingår i: BMC Evolutionary Biology. - : BioMed Central Ltd.. - 1471-2148. ; 9, s. 28-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The question of how genomic processes, such as gene duplication, give rise to co-ordinated organismal properties, such as emergence of new body plans, organs and lifestyles, is of importance in developmental and evolutionary biology. Herein, we focus on the diversification of the transforming growth factor-beta (TGF-beta) pathway -- one of the fundamental and versatile metazoan signal transduction engines. RESULTS: After an investigation of 33 genomes, we show that the emergence of the TGF-beta pathway coincided with appearance of the first known animal species. The primordial pathway repertoire consisted of four Smads and four receptors, similar to those observed in the extant genome of the early diverging tablet animal (Trichoplax adhaerens). We subsequently retrace duplications in ancestral genomes on the lineage leading to humans, as well as lineage-specific duplications, such as those which gave rise to novel Smads and receptors in teleost fishes. We conclude that the diversification of the TGF-beta pathway can be parsimoniously explained according to the 2R model, with additional rounds of duplications in teleost fishes. Finally, we investigate duplications followed by accelerated evolution which gave rise to an atypical TGF-beta pathway in free-living bacterial feeding nematodes of the genus Rhabditis. CONCLUSION: Our results challenge the view of well-conserved developmental pathways. The TGF-beta signal transduction engine has expanded through gene duplication, continually adopting new functions, as animals grew in anatomical complexity, colonized new environments, and developed an active immune system.
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| 5. |
- Huminiecki, Lukasz, et al.
(författare)
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Polyploidy and the evolution of complex traits.
- 2012
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Ingår i: International journal of evolutionary biology. - : Hindawi Limited. - 2090-052X .- 2090-8032. ; 2012, s. 292068-(12 pp.)
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Forskningsöversikt (refereegranskat)abstract
- We explore how whole-genome duplications (WGDs) may have given rise to complex innovations in cellular networks, innovations that could not have evolved through sequential single-gene duplications. We focus on two classical WGD events, one in bakers' yeast and the other at the base of vertebrates (i.e., two rounds of whole-genome duplication: 2R-WGD). Two complex adaptations are discussed in detail: aerobic ethanol fermentation in yeast and the rewiring of the vertebrate developmental regulatory network through the 2R-WGD. These two examples, derived from diverged branches on the eukaryotic tree, boldly underline the evolutionary potential of WGD in facilitating major evolutionary transitions. We close by arguing that the evolutionary importance of WGD may require updating certain aspects of modern evolutionary theory, perhaps helping to synthesize a new evolutionary systems biology.
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| 6. |
- Hurst, Laurence D., et al.
(författare)
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A simple metric of promoter architecture robustly predicts expression breadth of human genes suggesting that most transcription factors are positive regulators
- 2014
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Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 15:7, s. 413-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Conventional wisdom holds that, owing to the dominance of features such as chromatin level control, the expression of a gene cannot be readily predicted from knowledge of promoter architecture. This is reflected, for example, in a weak or absent correlation between promoter divergence and expression divergence between paralogs. However, an inability to predict may reflect an inability to accurately measure or employment of the wrong parameters. Here we address this issue through integration of two exceptional resources: ENCODE data on transcription factor binding and the FANTOM5 high-resolution expression atlas. Results: Consistent with the notion that in eukaryotes most transcription factors are activating, the number of transcription factors binding a promoter is a strong predictor of expression breadth. In addition, evolutionarily young duplicates have fewer transcription factor binders and narrower expression. Nonetheless, we find several binders and cooperative sets that are disproportionately associated with broad expression, indicating that models more complex than simple correlations should hold more predictive power. Indeed, a machine learning approach improves fit to the data compared with a simple correlation. Machine learning could at best moderately predict tissue of expression of tissue specific genes. Conclusions: We find robust evidence that some expression parameters and paralog expression divergence are strongly predictable with knowledge of transcription factor binding repertoire. While some cooperative complexes can be identified, consistent with the notion that most eukaryotic transcription factors are activating, a simple predictor, the number of binding transcription factors found on a promoter, is a robust predictor of expression breadth.
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| 7. |
- Hurst, Laurence D., et al.
(författare)
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The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome
- 2015
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Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 13:12
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Tidskriftsartikel (refereegranskat)abstract
- X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution.
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| 8. |
- Yeung, Andy Wai Kan, et al.
(författare)
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Dietary natural products and their potential to influence health and disease including animal model studies
- 2018
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Ingår i: Animal Science Papers and Reports. - : POLSKA AKAD NAUK, INST GENETYKI I HODOWLI ZWIERZAT. - 0860-4037. ; 36:4, s. 345-358
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Forskningsöversikt (refereegranskat)abstract
- Although biological and pharmacological effects of dietary natural products have been intensively studied, there has been no bibliometric analysis performed on this research field up to now. The current study has aimed to identify and analyze the manuscripts on dietary natural products and their potential to influence health and disease including studies using animal models. Data, including words from titles and abstracts, publication and citation data, have been extracted from Web of Science database and analyzed by the VOSviewer software. Our search has yielded 1,014 manuscripts. The ratio of original articles to reviews was identified to be 1.5:1. Over half of the manuscripts have been published since 2010. The manuscripts have been contributed by 4,301 authors from 1,445 organizations in 76 countries/territories and published in 499 journals. The results from the current study point out that scientific research focusing on the potential of dietary natural products to affect health and disease status (including animal model studies) is expanding, and suggests an increasing significance of this scientific area. With the progressive development and improvement of animal studies, it should be expected that animal models of different human diseases (especially civilization ones) would be an integral part of the research for the evaluation of pharmaceuticals originated from dietary natural products like plants or plant materials. Moreover, natural products can also be fed to animals to improve the quality of animal products, with numerous resulting functional effects.
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| 9. |
- Yeung, Andy Wai Kan, et al.
(författare)
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Resveratrol, a popular dietary supplement for human and animal health : Quantitative research literature analysis - a review
- 2019
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Ingår i: Animal Science Papers and Reports. - : POLSKA AKAD NAUK, INST GENETYKI I HODOWLI ZWIERZAT. - 0860-4037. ; 37:2, s. 103-118
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Forskningsöversikt (refereegranskat)abstract
- Resveratrol is a stilbene-type bioactive molecule with a broad spectrum of reported biological effects. In this sense, the current work provides a comprehensive literature analysis on resveratrol, representing a highly-researched commercially available dietary ingredient. Bibliometric data were identified by means of the search string TOPIC=("resveratrol*") and analyzed with the VOSviewer software, which yielded 17,561 publications extracted from the Web of Science Core Collection electronic database. 'I'he ratio of original articles to reviews was 9.5:1. More than half of the overall manuscripts have been published since 2013. Major contributing countries were USA, China, Italy, South Korea, and Spain. Most of the publications appeared in journals specialized in biochemistry and molecular biology, pharmacology and pharmacy, food science technology, cell biology, or oncology. The phytochemicals or phytochemical classes that were frequently mentioned in the keywords of analyzed publications included, in descending order: resveratrol, trans-resveratrol, polyphenols, flavonoids, quercetin, stilbenes, curcumin, piceatannol, cis-resveratrol, and anthocyanins.
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