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Wang Y, Deboer T. Hypnotic effects of melatonin depend on the environmental lighting conditions in the rat. J Pineal Res 2024; 76:e12928. [PMID: 38031385 DOI: 10.1111/jpi.12928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/01/2023]
Abstract
Acute effects of exogenous melatonin have been widely reported to promote sleep or induce drowsiness in human. However, testing of the hypnotic effects of melatonin in nocturnal rodents has yielded contradictory results. The latter may be associated with differences in concentration, lighting conditions, time of administration of melatonin, and possibly the type of analysis. In this study, electroencephalogram (EEG) and electromyogram were recorded in pigmented male Brown Norway rats under both light-dark (LD) and constant dark (DD) conditions. Melatonin was administered intraperitoneally at a moderate dose of 3 mg/kg, at either 1 h after lights on under LD condition or 1 h after the activity offset under DD condition. The dosage is known to be able to entrain nocturnal rodents in DD conditions, but does not change sleep in rodents in LD. Only the rats under DD conditions showed a significant reduction in nonrapid eye movement (NREM) sleep latency, while the NREM sleep power spectrum remained unaffected. Under LD condition, melatonin did not alter NREM and rapid eye movement (REM) sleep latency, and had only minor effects on the NREM sleep EEG. Regardless of lighting conditions, melatonin administration resulted in less, but longer episodes for all vigilance states suggesting increased vigilance state consolidation. In the discussion, we compare our results with a summary of previously published data concerning the hypnotic effects of melatonin in polysomnographic/EEG-confirmed sleep in humans and nocturnal rodents. In conclusion, the hypnotic effect of exogenous melatonin in nocturnal rodents not only depends on the time of day, and concentration, but is also influenced by the lighting conditions. Regardless of inducing sleep or not, melatonin may consolidate sleep and through that enhance sleep quality.
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Affiliation(s)
- Yumeng Wang
- Laboratory for Neurophysiology, Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tom Deboer
- Laboratory for Neurophysiology, Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
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2
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Slabejová G, Vidholdová Z, Šmidriaková M. Effect of Two Different Ageing Exposures on the Colour Stability of Transparent Polyurethane Finishing. Polymers (Basel) 2023; 15:3313. [PMID: 37571207 PMCID: PMC10422424 DOI: 10.3390/polym15153313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/13/2023] Open
Abstract
This paper deals with the influence of dark and light exposure on the colour change of a transparent two-component polyurethane surface finish. The surface finish with polyacrylic and aldehyde resin was applied to the surfaces of untreated and hydrothermally treated European beech, alder, Norway maple, and Paper birch wood. The test specimens were deposited indoors for 60 days. The colour values (lightness L*, redness + a*, yellowness + b*, chroma C*, hue angle h°) were expressed in the CIELAB system. The results showed that the colour difference of the finish surfaces of all hydrothermally treated wood species was 27-50% lower after the dark than when exposed to light. In the case of finished untreated wood, the colour difference was 51-73% lower after the dark than light exposure. Only the finished untreated and hydrothermally treated Norway maple wood surfaces showed similar and significant changes after both dark and light exposure. The lower value of the colour difference of the finished hydrothermally treated wood was due to the fact that steaming wood with saturated water steam has a positive effect on the overall colour stability of the finish and partial resistance to the initiation of photolytic reactions caused by light.
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Affiliation(s)
- Gabriela Slabejová
- Faculty of Wood Sciences and Technology, Department of Furniture and Wood Products, Technical University in Zvolen, 960 01 Zvolen, Slovakia; (G.S.); (M.Š.)
| | - Zuzana Vidholdová
- Faculty of Wood Sciences and Technology, Department of Wood Technology, Technical University in Zvolen, Masaryka 24, 960 01 Zvolen, Slovakia
| | - Mária Šmidriaková
- Faculty of Wood Sciences and Technology, Department of Furniture and Wood Products, Technical University in Zvolen, 960 01 Zvolen, Slovakia; (G.S.); (M.Š.)
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3
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Wang L, Doan PPT, Chuong NN, Lee HY, Kim JH, Kim J. Comprehensive transcriptomic analysis of age-, dark-, and salt-induced senescence reveals underlying mechanisms and key regulators of leaf senescence in Zoysia japonica. Front Plant Sci 2023; 14:1170808. [PMID: 37324695 PMCID: PMC10265201 DOI: 10.3389/fpls.2023.1170808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/27/2023] [Indexed: 06/17/2023]
Abstract
The lawn grass Zoysia japonica is widely cultivated for its ornamental and recreational value. However, its green period is subject to shortening, which significantly decreases the economic value of Z. japonica, especially for large cultivations. Leaf senescence is a crucial biological and developmental process that significantly influences the lifespan of plants. Moreover, manipulation of this process can improve the economic value of Z. japonica by extending its greening period. In this study, we conducted a comparative transcriptomic analysis using high-throughput RNA sequencing (RNA-seq) to investigate early senescence responses triggered by age, dark, and salt. Gene set enrichment analysis results indicated that while distinct biological processes were involved in each type of senescence response, common processes were also enriched across all senescence responses. The identification and validation of differentially expressed genes (DEGs) via RNA-seq and quantitative real-time PCR provided up- and down-regulated senescence markers for each senescence and putative senescence regulators that trigger common senescence pathways. Our findings revealed that the NAC, WRKY, bHLH, and ARF transcription factor (TF) groups are major senescence-associated TF families that may be required for the transcriptional regulation of DEGs during leaf senescence. In addition, we experimentally validated the senescence regulatory function of seven TFs including ZjNAP, ZjWRKY75, ZjARF2, ZjNAC1, ZjNAC083, ZjARF1, and ZjPIL5 using a protoplast-based senescence assay. This study provides new insight into the molecular mechanisms underlying Z. japonica leaf senescence and identifies potential genetic resources for enhancing its economic value by prolonging its green period.
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Affiliation(s)
- Lanshuo Wang
- Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju, Republic of Korea
| | - Phan Phuong Thao Doan
- Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju, Republic of Korea
| | - Nguyen Nguyen Chuong
- Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju, Republic of Korea
| | - Hyo-Yeon Lee
- Subtropical Horticulture Research Institute, Jeju National University, Jeju, Republic of Korea
- Department of Biotechnology, Jeju National University, Jeju, Republic of Korea
| | - Jin Hee Kim
- Subtropical Horticulture Research Institute, Jeju National University, Jeju, Republic of Korea
| | - Jeongsik Kim
- Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju, Republic of Korea
- Subtropical Horticulture Research Institute, Jeju National University, Jeju, Republic of Korea
- Faculty of Science Education, Jeju National University, Jeju, Republic of Korea
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4
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Roni MS, Sakil MA, Aktar MM, Takatsuka C, Mukae K, Inoue-Aono Y, Moriyasu Y. Hydrogen Peroxide Mediates Premature Senescence Caused by Darkness and Inorganic Nitrogen Starvation in Physcomitrium patens. Plants (Basel) 2022; 11:2280. [PMID: 36079662 PMCID: PMC9460043 DOI: 10.3390/plants11172280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 06/15/2023]
Abstract
Leaf senescence accompanied by yellowing and Rubisco degradation occurs prematurely in response to various stresses. However, signaling pathways between stress perception and senescence responses are not understood fully, although previous studies suggest the involvement of reactive oxygen species (ROS). While investigating the physiological functions of autophagy in Physcomitrium patens using wild-type (WT) and autophagy-deficient atg5 strains, we found that Physcomitrium colonies senesce prematurely under dark or nitrogen-deficient conditions, with atg5 senescing earlier than WT. In the present study, we measured cellular H2O2, and examined whether H2O2 mediates premature senescence in Physcomitrium colonies. Methyl viologen, an ROS generator, increased cellular H2O2 levels and caused senescence-like symptoms. H2O2 levels were also elevated to the same plateau levels in WT and atg5 under dark or nitrogen-deficient conditions. The ROS scavenger N-acetylcysteine and the ROS source inhibitor carbonyl cyanide m-chlorophenylhydrazone inhibited the increase in H2O2 levels as well as senescence. Upon transfer to a nitrogen-deficient medium, H2O2 levels increased earlier in atg5 than in WT by ~18 h, whereas atg5 yellowed earlier by >2 days. We conclude that the increased H2O2 levels under dark or nitrogen-deficient conditions mediate premature senescence in Physcomitrium but do not explain the different senescence responses of WT and atg5 cells.
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Affiliation(s)
- Md. Shyduzzaman Roni
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
- Department of Horticulture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh
| | - Md. Arif Sakil
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
- Department of Biochemistry and Molecular Biology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Most Mohoshena Aktar
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
- Department of Agronomy, Hajee Mohammad Danesh Science and Technology University, Dinajpur 5200, Bangladesh
| | | | - Kyosuke Mukae
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
- Research Institute for Clinical Oncology, Saitama Cancer Center, Saitama 362-0806, Japan
| | - Yuko Inoue-Aono
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Yuji Moriyasu
- Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
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5
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Ferenchak NN, Gutierrez RE, Singleton PA. Shedding light on the pedestrian safety crisis: An analysis across the injury severity spectrum by lighting condition. Traffic Inj Prev 2022; 23:434-439. [PMID: 35878003 DOI: 10.1080/15389588.2022.2100362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 06/28/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVE Pedestrian fatalities in the United States increased 51% from 2009 to 2019. During that time, pedestrian fatalities occurring at night increased by 63.7%, compared to a 17.6% increase for pedestrian fatalities occurring during daylight conditions. Have there also been increases in serious, minor, and possible pedestrian injuries (i.e., have all pedestrian collisions been occurring more frequently)? Have pedestrian collisions been getting more severe (i.e., are there now higher proportions of more severe injuries)? Have trends differed between night and day? What role does street lighting play in the nighttime trends? METHODS We analyzed pedestrian fatalities, serious injuries, minor injuries, and possible injuries that occurred in California, North Carolina, and Texas from 2010 to 2019 using linear regressions to explore the strength and statistical significance of trends. We then parsed these trends by lighting condition, exploring outcomes during the day and night and with and without street lighting. RESULTS Findings suggest that increases in daytime minor (7.9%) and possible (7.5%) injuries closely mirrored increases in population (9.8%). Increases in daytime fatal/serious injuries were significantly higher (43.1% and 35.1%, respectively), suggesting worsening severities during the day. Increases in nighttime minor/possible injuries (31.9% and 27.6%, respectively) were significantly larger than those during the day, suggesting that pedestrian collisions are occurring more frequently at night. Substantial increases in nighttime fatal/serious injuries (78.0% and 74.7%, respectively) likely reflect a combination of worsening severity (seen throughout the day) and increasing frequency (seen particularly at night). A pedestrian injured in the dark was found to be 5.0 times more likely to be killed than a pedestrian injured during the day. While a lack of street lighting does not seem to be the cause of the disproportionate increase in pedestrian injuries at night, pedestrians struck without a street light were 2.4 times more likely to be killed than those struck in the presence of a street light. CONCLUSIONS As we find ourselves in the midst of a pedestrian safety crisis, understanding that severities have increased throughout the entire day and frequencies have increased particularly at night helps illuminate a path forward.
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Affiliation(s)
- Nicholas N Ferenchak
- Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, New Mexico
| | - Risa E Gutierrez
- Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, New Mexico
| | - Patrick A Singleton
- Department of Civil and Environmental Engineering, Utah State University, Logan, Utah
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6
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Esaki Y, Obayashi K, Saeki K, Fujita K, Iwata N, Kitajima T. Effect of nighttime bedroom light exposure on mood episode relapses in bipolar disorder. Acta Psychiatr Scand 2022; 146:64-73. [PMID: 35253206 DOI: 10.1111/acps.13422] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 02/26/2022] [Indexed: 12/26/2022]
Abstract
OBJECTIVE A previous cross-sectional study reported that nighttime light is associated with increased occurrence of manic symptoms in bipolar disorder; however, the longitudinal association between nighttime light and subsequent mood episode relapses remains unclear. We determined whether bedroom nighttime light was associated with mood episode relapses in patients with bipolar disorder. METHODS This prospective cohort study included 172 outpatients with bipolar disorder who participated in an Association between the Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study. A portable photometer was used to measure illuminance in the bedroom from bedtime to rising time during 7 consecutive nights for baseline assessment. Then, the participants were assessed at a 2-year follow-up for mood episode relapses. RESULTS Of the 172 participants, 157 (91%) completed the 2-year follow-up, and 39 (22%) experienced manic or hypomanic episodes (with or without mixed features), during that time. In the Cox proportional-hazards model, the hazard ratio (HR) for manic/hypomanic episode relapses was significantly higher when the average nighttime illuminance was ≥3 lux (n = 71) than when it was <3 lux (n = 101; HR, 2.54; 95% confidence interval (CI), 1.33-4.84). In the multivariable model adjusted for a propensity score in relation to nighttime light, the relationship remained significant (HR, 2.17; 95% CI, 1.04-4.52). The association between nighttime light and depressive episode relapses was not significantly different. CONCLUSIONS Keeping the bedroom dark at night may prevent hypomanic and manic episodes.
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Affiliation(s)
- Yuichi Esaki
- Department of Psychiatry, Okehazama Hospital, Aichi, Japan.,Department of Psychiatry, Fujita Health University School of Medicine, Aichi, Japan
| | - Kenji Obayashi
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
| | - Keigo Saeki
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
| | - Kiyoshi Fujita
- Department of Psychiatry, Okehazama Hospital, Aichi, Japan.,The Neuroscience Research Center, Aichi, Japan
| | - Nakao Iwata
- Department of Psychiatry, Fujita Health University School of Medicine, Aichi, Japan
| | - Tsuyoshi Kitajima
- Department of Psychiatry, Fujita Health University School of Medicine, Aichi, Japan
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7
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Cui Y, Bian J, Lv Y, Li J, Deng XW, Liu X. Analysis of the Transcriptional Dynamics of Regulatory Genes During Peanut Pod Development Caused by Darkness and Mechanical Stress. Front Plant Sci 2022; 13:904162. [PMID: 35693161 PMCID: PMC9178256 DOI: 10.3389/fpls.2022.904162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 04/26/2022] [Indexed: 06/15/2023]
Abstract
Peanut is an oil crop with important economic value that is widely cultivated around the world. It blooms on the ground but bears fruit underground. When the peg penetrates the ground, it enters a dark environment, is subjected to mechanical stress from the soil, and develops into a normal pod. When a newly developed pod emerges from the soil, it turns green and stops growing. It has been reported that both darkness and mechanical stress are necessary for normal pod development. In this study, we investigated changes in gene expression during the reverse process of peg penetration: developmental arrest caused by pod (Pattee 3 pods) excavation. Bagging the aerial pods was used to simulate loss of mechanical pressure, while direct exposure of the aerial pods was used to simulate loss of both mechanical pressure and darkness. After the loss of mechanical stress and darkness, the DEGs were significantly enriched in photosynthesis, photosynthesis-antenna proteins, plant-pathogen interaction, DNA replication, and circadian rhythm pathways. The DNA replication pathway was enriched by down-regulated genes, and the other four pathways were enriched by upregulated genes. Upregulated genes were also significantly enriched in protein ubiquitination and calmodulin-related genes, highlighting the important role of ubiquitination and calcium signaling in pod development. Further analysis of DEGs showed that phytochrome A (Phy A), auxin response factor 9 (IAA9), and mechanosensitive ion channel protein played important roles in geocarpy. The expression of these two genes increased in subterranean pods but decreased in aerial pods. Based on a large number of chloroplast-related genes, calmodulin, kinases, and ubiquitin-related proteins identified in this study, we propose two possible signal transduction pathways involved in peanut geocarpy, namely, one begins in chloroplasts and signals down through phosphorylation, and the other begins during abiotic stress and signals down through calcium signaling, phosphorylation, and ubiquitination. Our study provides valuable information about putative regulatory genes for peanut pod development and contributes to a better understanding of the biological phenomenon of geocarpy.
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Affiliation(s)
- Yuanyuan Cui
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
- School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Jianxin Bian
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
| | - Yuying Lv
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
| | - Jihua Li
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
| | - Xing Wang Deng
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
- School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Xiaoqin Liu
- Shandong Laboratory for Advanced Agricultural Sciences at Weifang, Peking University Institute of Advanced Agricultural Science, Weifang, China
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8
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Cabrera J, Conesa CM, Del Pozo JC. May the dark be with roots: a perspective on how root illumination may bias in vitro research on plant-environment interactions. New Phytol 2022; 233:1988-1997. [PMID: 34942016 DOI: 10.1111/nph.17936] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Roots anchor plants to the soil, providing them with nutrients and water while creating a defence network and facilitating beneficial interactions with a multitude of living organisms and climatological conditions. To facilitate morphological and molecular studies, root research has been conducted using in vitro systems. However, under natural conditions, roots grow in the dark, mainly in the absence of illumination, except for the relatively low illumination of the upper soil surface, and this has been largely ignored. Here, we discuss the results found over the last decade on how experimental exposure of roots to light may bias root development and responses through the alteration of hormonal signalling, cytoskeleton organization, reactive oxygen species or the accumulation of flavonoids, among other factors. Illumination alters the uptake of nutrients or water, and also affects the response of the roots to abiotic stresses and root interactions with the microbiota. Furthermore, we review in vitro systems created to maintain roots in darkness, and provide a comparative analysis of root transcriptomes obtained with these devices. Finally, we identify other experimental variables that should be considered to better mimic soil conditions, whose improvement would benefit studies using in vitro cultivation or enclosed ecosystems.
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Affiliation(s)
- Javier Cabrera
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/Consejo Superior de Investigaciones Científicas (UPM-INIA/CSIC), UPM, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Carlos M Conesa
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/Consejo Superior de Investigaciones Científicas (UPM-INIA/CSIC), UPM, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain
- Escuela Técnica Superior de Ingeniería Agronómica, Agroambiental y de Biosistemas (ETSIAAB), Universidad Politécnica de Madrid, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Juan C Del Pozo
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/Consejo Superior de Investigaciones Científicas (UPM-INIA/CSIC), UPM, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Madrid, Spain
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Abstract
Although ethnic diversity is rising in the United States, educational resources continue to lag behind, as evidenced by prior studies highlighting limited skin of color representation in dermatology resources. The objective of this study was to evaluate the representation of skin tones in three dermatology journals commonly used in resident education and journal clubs. Overall, 5.6% (Journal of the American Academy of Dermatology), 4.1% (JAMA Dermatology), and 8.3% (Pediatric Dermatology) of images in the journals were depicted on "Dark" skin (Fitzpatrick V-VI). Disparities in skin of color representation exist in three dermatology journals used in medical education in the United States.
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Affiliation(s)
| | - Yesul Kim
- Department of Dermatology, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA
| | - Andrea L Zaenglein
- Department of Dermatology, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA.,Department of Pediatrics, Penn State Children's Hospital, Hershey, PA, USA
| | - Lauren Claire Hollins
- Department of Dermatology, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA
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10
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Riegler S, Servi L, Scarpin MR, Godoy Herz MA, Kubaczka MG, Venhuizen P, Meyer C, Brunkard JO, Kalyna M, Barta A, Petrillo E. Light regulates alternative splicing outcomes via the TOR kinase pathway. Cell Rep 2021; 36:109676. [PMID: 34496244 PMCID: PMC8547716 DOI: 10.1016/j.celrep.2021.109676] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 05/18/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022] Open
Abstract
For plants, light is the source of energy and the most relevant regulator of growth and adaptations to the environment by inducing changes in gene expression at various levels, including alternative splicing. Light-triggered chloroplast retrograde signals control alternative splicing in Arabidopsis thaliana. Here, we provide evidence that light regulates the expression of a core set of splicing-related factors in roots. Alternative splicing responses in roots are not directly caused by light but are instead most likely triggered by photo-synthesized sugars. The target of rapamycin (TOR) kinase plays a key role in this shoot-to-root signaling pathway. Knocking down TOR expression or pharmacologically inhibiting TOR activity disrupts the alternative splicing responses to light and exogenous sugars in roots. Consistently, splicing decisions are modulated by mitochondrial activity in roots. In conclusion, by activating the TOR pathway, sugars act as mobile signals to coordinate alternative splicing responses to light throughout the whole plant. Riegler et al. reveal a central role for TOR kinase paired with retrograde signaling in alternative splicing regulation by light in roots and, to a certain extent, in leaves. Activating the TOR pathway, sugars act as mobile signals to coordinate alternative splicing responses to light throughout the whole plant.
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Affiliation(s)
- Stefan Riegler
- Department of Applied Genetics and Cell Biology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Lucas Servi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología, Molecular, y Celular, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), C1428EHA, Buenos Aires, Argentina
| | - M Regina Scarpin
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Plant Gene Expression Center, US Department of Agriculture, Agricultural Research Service, Albany, CA 94710, USA
| | - Micaela A Godoy Herz
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología, Molecular, y Celular, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), C1428EHA, Buenos Aires, Argentina
| | - María G Kubaczka
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología, Molecular, y Celular, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), C1428EHA, Buenos Aires, Argentina
| | - Peter Venhuizen
- Department of Applied Genetics and Cell Biology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Christian Meyer
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National de la Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Jacob O Brunkard
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Plant Gene Expression Center, US Department of Agriculture, Agricultural Research Service, Albany, CA 94710, USA; Laboratory of Genetics, University of Wisconsin, Madison, Madison, WI 53706, USA
| | - Maria Kalyna
- Department of Applied Genetics and Cell Biology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Andrea Barta
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter Campus, 1030 Vienna, Austria
| | - Ezequiel Petrillo
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología, Molecular, y Celular, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), C1428EHA, Buenos Aires, Argentina.
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11
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Czékus Z, Kukri A, Hamow KÁ, Szalai G, Tari I, Ördög A, Poór P. Activation of Local and Systemic Defence Responses by Flg22 Is Dependent on Daytime and Ethylene in Intact Tomato Plants. Int J Mol Sci 2021; 22:ijms22158354. [PMID: 34361121 PMCID: PMC8348740 DOI: 10.3390/ijms22158354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/29/2021] [Accepted: 07/31/2021] [Indexed: 02/07/2023] Open
Abstract
The first line of plant defence responses against pathogens can be induced by the bacterial flg22 and can be dependent on various external and internal factors. Here, we firstly studied the effects of daytime and ethylene (ET) using Never ripe (Nr) mutants in the local and systemic defence responses of intact tomato plants after flg22 treatments. Flg22 was applied in the afternoon and at night and rapid reactions were detected. The production of hydrogen peroxide and nitric oxide was induced by flg22 locally, while superoxide was induced systemically, in wild type plants in the light period, but all remained lower at night and in Nr leaves. Flg22 elevated, locally, the ET, jasmonic acid (JA) and salicylic acid (SA) levels in the light period; these levels did not change significantly at night. Expression of Pathogenesis-related 1 (PR1), Ethylene response factor 1 (ERF1) and Defensin (DEF) showed also daytime- and ET-dependent changes. Enhanced ERF1 and DEF expression and stomatal closure were also observable in systemic leaves of wild type plants in the light. These data demonstrate that early biotic signalling in flg22-treated leaves and distal ones is an ET-dependent process and it is also determined by the time of day and inhibited in the early night phase.
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Affiliation(s)
- Zalán Czékus
- Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary; (Z.C.); (A.K.); (I.T.); (A.Ö.)
- Doctoral School of Biology, University of Szeged, 6726 Szeged, Hungary
| | - András Kukri
- Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary; (Z.C.); (A.K.); (I.T.); (A.Ö.)
| | - Kamirán Áron Hamow
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, 2462 Martonvásár, Hungary; (K.Á.H.); (G.S.)
| | - Gabriella Szalai
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, 2462 Martonvásár, Hungary; (K.Á.H.); (G.S.)
| | - Irma Tari
- Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary; (Z.C.); (A.K.); (I.T.); (A.Ö.)
| | - Attila Ördög
- Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary; (Z.C.); (A.K.); (I.T.); (A.Ö.)
| | - Péter Poór
- Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, 6726 Szeged, Hungary; (Z.C.); (A.K.); (I.T.); (A.Ö.)
- Correspondence:
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12
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Iqbal Z, Iqbal MS, Hashem A, Abd_Allah EF, Ansari MI. Plant Defense Responses to Biotic Stress and Its Interplay With Fluctuating Dark/Light Conditions. Front Plant Sci 2021; 12:631810. [PMID: 33763093 PMCID: PMC7982811 DOI: 10.3389/fpls.2021.631810] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 02/08/2021] [Indexed: 05/24/2023]
Abstract
Plants are subjected to a plethora of environmental cues that cause extreme losses to crop productivity. Due to fluctuating environmental conditions, plants encounter difficulties in attaining full genetic potential for growth and reproduction. One such environmental condition is the recurrent attack on plants by herbivores and microbial pathogens. To surmount such attacks, plants have developed a complex array of defense mechanisms. The defense mechanism can be either preformed, where toxic secondary metabolites are stored; or can be inducible, where defense is activated upon detection of an attack. Plants sense biotic stress conditions, activate the regulatory or transcriptional machinery, and eventually generate an appropriate response. Plant defense against pathogen attack is well understood, but the interplay and impact of different signals to generate defense responses against biotic stress still remain elusive. The impact of light and dark signals on biotic stress response is one such area to comprehend. Light and dark alterations not only regulate defense mechanisms impacting plant development and biochemistry but also bestow resistance against invading pathogens. The interaction between plant defense and dark/light environment activates a signaling cascade. This signaling cascade acts as a connecting link between perception of biotic stress, dark/light environment, and generation of an appropriate physiological or biochemical response. The present review highlights molecular responses arising from dark/light fluctuations vis-à-vis elicitation of defense mechanisms in plants.
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Affiliation(s)
- Zahra Iqbal
- Molecular Crop Research Unit, Department of Biochemistry, Chulalongkorn University, Bangkok, Thailand
| | | | - Abeer Hashem
- Botany and Microbiology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
- Mycology and Plant Disease Survey Department, Plant Pathology Research Institute, ARC, Giza, Egypt
| | - Elsayed Fathi Abd_Allah
- Plant Production Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
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13
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Moreno-Ruiz D, Fuchs A, Missbach K, Schuhmacher R, Zeilinger S. Influence of Different Light Regimes on the Mycoparasitic Activity and 6-Pentyl-α-pyrone Biosynthesis in Two Strains of Trichoderma atroviride. Pathogens 2020; 9:pathogens9100860. [PMID: 33096850 PMCID: PMC7589932 DOI: 10.3390/pathogens9100860] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 01/09/2023] Open
Abstract
The ascomycete Trichoderma atroviride is well known for its mycoparasitic lifestyle. Similar to other organisms, light is an important cue for T. atroviride. However, besides triggering of conidiation, little is known on the physiological responses of T. atroviride to light. In this study, we analyzed how cultivation under different light wavelengths and regimes impacted the behavior of two T. atroviride wild-type strains: IMI206040 and P1. While colony extension of both strains was slightly affected by light, massive differences in their photoconidation responses became evident. T. atroviride P1 colonies conidiated under all conditions tested including growth in complete darkness, while IMI206040 required white, blue or green light to trigger asexual reproduction. Interestingly, deletion of the stress-activated MAP kinase-encoding gene tmk3 abolished the ability of strain P1 to conidiate in red and yellow light as well as in darkness. Furthermore, light-dependent differences in the mycoparasitic activity and in the biosynthesis of the secondary metabolite 6-pentyl-α-pyrone (6-PP) became evident. 6-PP production was highest upon dark incubation, while light, especially exposure to white light as light/dark cycles, had an inhibitory effect on its biosynthesis. We conclude that the response of T. atroviride to light is strain-dependent and impacts differentiation, mycoparasitism, and 6-PP production; hence, this should be considered in experiments testing the mycoparasitic activity of these fungi.
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Affiliation(s)
- Dubraska Moreno-Ruiz
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
| | - Alessandro Fuchs
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
| | - Kristina Missbach
- Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences Vienna (BOKU), 1180 Tulln, Austria; (K.M.); (R.S.)
| | - Rainer Schuhmacher
- Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences Vienna (BOKU), 1180 Tulln, Austria; (K.M.); (R.S.)
| | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
- Correspondence:
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Deepika, Ankit, Sagar S, Singh A. Dark-Induced Hormonal Regulation of Plant Growth and Development. Front Plant Sci 2020; 11:581666. [PMID: 33117413 PMCID: PMC7575791 DOI: 10.3389/fpls.2020.581666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/16/2020] [Indexed: 05/04/2023]
Abstract
The sessile nature of plants has made them extremely sensitive and flexible toward the constant flux of the surrounding environment, particularly light and dark. The light is perceived as a signal by specific receptors which further transduce the information through the signaling intermediates and effector proteins to modulate gene expression. Signal transduction induces changes in hormone levels that alters developmental, physiological and morphological processes. Importance of light for plants growth is well recognized, but a holistic understanding of key molecular and physiological changes governing plants development under dark is awaited. Here, we describe how darkness acts as a signal causing alteration in hormone levels and subsequent modulation of the gene regulatory network throughout plant life. The emphasis of this review is on dark mediated changes in plant hormones, regulation of signaling complex COP/DET/FUS and the transcription factors PIFs which affects developmental events such as apical hook development, elongated hypocotyls, photoperiodic flowering, shortened roots, and plastid development. Furthermore, the role of darkness in shade avoidance and senescence is discussed.
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Affiliation(s)
| | | | | | - Amarjeet Singh
- National Institute of Plant Genome Research, New Delhi, India
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15
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Werner C, Fasbender L, Romek KM, Yáñez-Serrano AM, Kreuzwieser J. Heat Waves Change Plant Carbon Allocation Among Primary and Secondary Metabolism Altering CO 2 Assimilation, Respiration, and VOC Emissions. Front Plant Sci 2020; 11:1242. [PMID: 32922421 PMCID: PMC7456945 DOI: 10.3389/fpls.2020.01242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 07/29/2020] [Indexed: 05/17/2023]
Abstract
Processes controlling plant carbon allocation among primary and secondary metabolism, i.e., carbon assimilation, respiration, and VOC synthesis are still poorly constrained, particularly regarding their response to stress. To investigate these processes, we simulated a 10-day 38°C heat wave, analysing real-time carbon allocation into primary and secondary metabolism in the Mediterranean shrub Halimium halimifolium L. We traced position-specific 13C-labeled pyruvate into daytime VOC and CO2 emissions and during light-dark transition. Net CO2 assimilation strongly declined under heat, due to three-fold higher respiration rates. Interestingly, day respiration also increased two-fold. Decarboxylation of the C1-atom of pyruvate was the main process driving daytime CO2 release, whereas the C2-moiety was not decarboxylated in the TCA cycle. Heat induced high emissions of methanol, methyl acetate, acetaldehyde as well as mono- and sesquiterpenes, particularly during the first two days. After 10-days of heat a substantial proportion of 13C-labeled pyruvate was allocated into de novo synthesis of VOCs. Thus, during extreme heat waves high respiratory losses and reduced assimilation can shift plants into a negative carbon balance. Still, plants enhanced their investment into de novo VOC synthesis despite associated metabolic CO2 losses. We conclude that heat stress re-directed the proportional flux of key metabolites into pathways of VOC biosynthesis most likely at the expense of reactions of plant primary metabolism, which might highlight their importance for stress protection.
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Affiliation(s)
- Christiane Werner
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
- *Correspondence: Christiane Werner,
| | - Lukas Fasbender
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
| | | | - Ana Maria Yáñez-Serrano
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
- Center of Ecological Research and Forest Applications (CREAF), Universitat Autònoma de Barcelona, Barcelona, Spain
- Global Ecology Unit CREAF-CSIC-UAB, Cerdanyola del Vallès, Barcelona, Spain
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Khani A, Mustafar F, Rainer G. Distinct Frequency Specialization for Detecting Dark Transients in Humans and Tree Shrews. Cell Rep 2019; 23:2405-2415. [PMID: 29791851 DOI: 10.1016/j.celrep.2018.04.076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 02/23/2018] [Accepted: 04/13/2018] [Indexed: 10/16/2022] Open
Abstract
Despite well-known privileged perception of dark over light stimuli, it is unknown to what extent this dark dominance is maintained when visual transients occur in rapid succession, for example, during perception of moving stimuli. Here, we address this question using dark and light transients presented at different flicker frequencies. Although both human participants and tree shrews exhibited dark dominance for temporally modulated transients, these occurred at different flicker frequencies, namely, at 11 Hz in humans and 40 Hz and higher in tree shrews. Tree shrew V1 neuronal activity confirmed that differences between light and dark flicker were maximal at 40 Hz, corresponding closely to behavioral findings. These findings suggest large differences in flicker perception between humans and tree shrews, which may be related to the lifestyle of these species. A specialization for detecting dark transients at high temporal frequencies may thus be adaptive for tree shrews, which are particularly fast-moving small mammals.
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Affiliation(s)
- Abbas Khani
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland; Functional Brain Mapping Laboratory, Department of Basic Neurosciences, University of Geneva, 1211 Geneva, Switzerland.
| | - Faiz Mustafar
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland; Department of Neurosciences, Universiti Sains Malaysia, 16150 Kelantan, Malaysia
| | - Gregor Rainer
- Visual Cognition Laboratory, Department of Medicine, University of Fribourg, 1700 Fribourg, Switzerland.
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Yang H, Klopotek Y, Hajirezaei MR, Zerche S, Franken P, Druege U. Role of auxin homeostasis and response in nitrogen limitation and dark stimulation of adventitious root formation in petunia cuttings. Ann Bot 2019; 124:1053-1066. [PMID: 31181150 PMCID: PMC6881223 DOI: 10.1093/aob/mcz095] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/05/2019] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND AIMS Adventitious root (AR) formation in Petunia hybrida is inhibited by low nitrogen fertilization of stock plants but promoted by dark incubation of cuttings before planting. We investigated whether the plant hormone auxin is involved in nitrogen- and dark-mediated AR formation. METHODS Concentrations of indole-3-acetic acid (IAA) and RNA accumulation of genes controlling auxin homeostasis and function were monitored in the stem base in response to high versus low nitrogen supply to stock plants and to temporal dark vs. light exposure of cuttings by use of GC-MS/MS, a petunia-specific microarray and quantitative RT-PCR. Auxin source capacity, polar auxin transport in cuttings and auxin concentration in the rooting zone were manipulated to investigate the functional contribution of auxin homeostasis and response to the effects of nitrogen fertilization and dark exposure on rooting. KEY RESULTS The nitrogen content of cuttings had only a marginal effect on IAA concentration in the stem base. Dark incubation enhanced the accumulation of IAA in the stem base during AR induction independent of nitrogen level. Early IAA accumulation in the dark depended on the upper shoot as an auxin source and was enhanced after apical IAA supply. Dark exposure stimulated RNA accumulation of auxin-related genes. In particular, expression of Ph-PIN1 and of genes controlling auxin signalling, including Ph-IAA14, Ph-ARF8, Ph-ARF10 and Ph-SAUR14, was enhanced, while the latter four were repressed in nitrogen-limited cuttings, particularly in the dark. Dark stimulation of rooting depended on polar auxin transport. Basal auxin application partially substituted the effect of dark exposure on rooting, whereas the auxin response of AR formation was strongly depressed by nitrogen limitation. CONCLUSIONS Increased auxin delivery from the upper shoot and enhanced auxin signalling in the stem base contribute to dark-stimulated AR formation, while nitrogen limitation inhibits AR formation downstream of the auxin signal.
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Affiliation(s)
- Huaiyu Yang
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Erfurt, Germany
| | - Yvonne Klopotek
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Erfurt, Germany
| | | | - Siegfried Zerche
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Erfurt, Germany
| | - Philipp Franken
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Erfurt, Germany
| | - Uwe Druege
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), Erfurt, Germany
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18
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Berkowitz BA, Podolsky RH, Lins-Childers KM, Li Y, Qian H. Outer Retinal Oxidative Stress Measured In Vivo Using QUEnch-assiSTed (QUEST) OCT. Invest Ophthalmol Vis Sci 2019; 60:1566-1570. [PMID: 30995313 PMCID: PMC6736344 DOI: 10.1167/iovs.18-26164] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 03/05/2019] [Indexed: 02/06/2023] Open
Abstract
Purpose To test the hypothesis that oxidative stress in the outer retina (OR = distance from external limiting membrane to the retinal pigment epithelium-choroid boundary) can be detected by using antioxidants (AOs) to correct an impaired light-evoked response as measured by optical coherence tomography (OCT). Methods C57BL/6J mice were maintained in the dark for ∼20 hours and studied by OCT before and after 1 hour of light exposure. OR thickness in dark or light was measured, and the light-dark difference (i.e., the photoresponse) was calculated. Subgroups of mice were given either saline or d-cis-diltiazem (an inducer of transient and nondamaging OR oxidative stress) ± methylene blue (24 hours before examination) and α-lipoic acid (1 hour before examination); one group was kept only in the dark and given only AOs. Results In uninjected or saline-injected control mice, the OR showed a similar and reproducible light-induced expansion; dark-adapted mice given AOs did not increase dark-adapted OR thickness. The d-cis-diltiazem-treated mice had no photoresponse (P > 0.05). The d-cis-diltiazem-treated mice given AOs corrected (P < 0.05) the suppressed OR photoresponse, indicating the presence of oxidative stress. Conclusions QUEnch-assiSTed (QUEST) OCT reproduced results from previous gold standard assays, showing that oxidative stress impairs the OR photoresponse and that d-cis-diltiazem produces OR oxidative stress. We envision future applications of QUEST OCT in a range of oxidative stress-based retinopathies.
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Affiliation(s)
- Bruce A. Berkowitz
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Robert H. Podolsky
- Beaumont Research Institute, Beaumont Health, Royal Oak, Michigan, United States
| | | | - Yichao Li
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
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Gallé Á, Czékus Z, Bela K, Horváth E, Ördög A, Csiszár J, Poór P. Plant Glutathione Transferases and Light. Front Plant Sci 2019; 9:1944. [PMID: 30687349 PMCID: PMC6333738 DOI: 10.3389/fpls.2018.01944] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/13/2018] [Indexed: 05/09/2023]
Abstract
The activity and expression of glutathione transferases (GSTs) depend on several less-known endogenous and well-described exogenous factors, such as the developmental stage, presence, and intensity of different stressors, as well as on the absence or presence and quality of light, which to date have received less attention. In this review, we focus on discussing the role of circadian rhythm, light quality, and intensity in the regulation of plant GSTs. Recent studies demonstrate that diurnal regulation can be recognized in GST activity and gene expression in several plant species. In addition, the content of one of their co-substrates, reduced glutathione (GSH), also shows diurnal changes. Darkness, low light or shade mostly reduces GST activity, while high or excess light significantly elevates both the activity and expression of GSTs and GSH levels. Besides the light-regulated induction and dark inactivation of GSTs, these enzymes can also participate in the signal transduction of visible and UV light. For example, red light may alleviate the harmful effects of pathogens and abiotic stressors by increasing GST activity and expression, as well as GSH content in leaves of different plant species. Based on this knowledge, further research on plants (crops and weeds) or organs and temporal regulation of GST activity and gene expression is necessary for understanding the complex regulation of plant GSTs under various light conditions in order to increase the yield and stress tolerance of plants in the changing environment.
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Affiliation(s)
- Ágnes Gallé
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
| | - Zalán Czékus
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
| | - Krisztina Bela
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
| | - Edit Horváth
- Biological Research CentreInstitute of Plant Biology, Szeged, Hungary
| | - Attila Ördög
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
| | - Jolán Csiszár
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
| | - Péter Poór
- Department of Plant Biology, Faculty of Science and InformaticsUniversity of Szeged, Szeged, Hungary
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Zhang J, Zhu C, Lv J, Zhang W, Feng J. Preparation of Colorful, Infrared-Reflective, and Superhydrophobic Polymer Films with Obvious Resistance to Dust Deposition. ACS Appl Mater Interfaces 2018; 10:40219-40227. [PMID: 30387590 DOI: 10.1021/acsami.8b12567] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In recent years, polymer films containing deep color and near-infrared (NIR)-reflective pigments have received much attention for their potential applications in energy-saving fields. However, in practical environments, dust present in the air is easily adsorbed and adheres to the surface of these films, thus gradually reducing their NIR reflectance. In this work, black or deep-red infrared-reflective pigments were firstly mixed with melted low-density polyethylene (LDPE) and then the resulting composite was thermally pressed on to a metal template possessing micro- and nanostructure surface roughness. After being cooled to a suitable temperature, the LDPE composite film was peeled from the template. Ultraviolet-visible-near-infrared spectroscopy and an indoor infrared lamp irradiation test both confirmed that the prepared films exhibit high NIR reflectance and high heat reflectance. Moreover, due to the stretching-controlled micromolding process, the films all exhibited a superhydrophobic (SH) property. After incubation in outdoor conditions for 1 month, the NIR reflectance of the SH films remained almost consistent; however, the films that did not possess SH property showed a marked decrease in their ability to reflect NIR radiation. By a combination of scanning electron microscopy imaging, we conclude that our films are able to resist dust deposition and thus avoid deterioration of their infrared-reflective properties. We believe that these colorful, infrared-reflective, SH, and cost-effective films have potential application for reducing energy consumption where minimal solar irradiation is required.
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Affiliation(s)
- Jing Zhang
- College of Materials Science & Engineering , Zhejiang University of Technology , Hangzhou 310014 , China
| | - Chenxi Zhu
- College of Materials Science & Engineering , Zhejiang University of Technology , Hangzhou 310014 , China
| | - Jian Lv
- College of Materials Science & Engineering , Zhejiang University of Technology , Hangzhou 310014 , China
| | - Weicheng Zhang
- College of Materials Science & Engineering , Zhejiang University of Technology , Hangzhou 310014 , China
| | - Jie Feng
- College of Materials Science & Engineering , Zhejiang University of Technology , Hangzhou 310014 , China
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21
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Ji HG, Lee YR, Lee MS, Hwang KH, Park CY, Kim EH, Park JS, Hong YS. Diverse Metabolite Variations in Tea (Camellia sinensis L.) Leaves Grown Under Various Shade Conditions Revisited: A Metabolomics Study. J Agric Food Chem 2018; 66:1889-1897. [PMID: 29409322 DOI: 10.1021/acs.jafc.7b04768] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
With the increase of tea (Camellia sinensis) consumption, its chemical or metabolite compositions play a crucial role in the determination of tea quality. In general, metabolite compositions of fresh tea leaves including shoots depend on plucking seasons and tea cultivators. Therefore, choosing a specific plucking time of tea leaves can provide use-specified tea products. Artificial control of tea growing, typically shade treatments, can lead to significant changes of the tea metabolite compositions. However, metabolic characteristics of tea grown under various shade treatment conditions remain unclear. Therefore, the objective of the current study was to explore effects of various shade conditions on metabolite compositions of tea through a 1H NMR-based metabolomics approach. It was noteworthy that the levels of catechins and their derivatives were only influenced at the initial time of shade treatments while most amino acids were upregulated as amounts of shade and periods were increased: that is, the levels of alanine, asparagine, aspartate, isoleucine, threonine, leucine, and valine in fresh tea leaves were conspicuously elevated when shade levels were raised from 90% to 100% and when period of shade treatments was increased by 20 days. Such increased synthesis of amino acids along with large reductions of glucose level reflected carbon starvation under the dark conditions, indicating remarkable proteolysis in the chloroplast of tea leaves. This study provides important information about making amino acid-enhanced tea products based on global characteristics of diverse tea leaf metabolites induced by various shade treatment conditions.
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Affiliation(s)
- Hyang-Gi Ji
- Division of Food and Nutrition, Chonnam National University , Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea
| | - Yeong-Ran Lee
- Applied Technology & Research Division, R&D Center, AmorePacific Corporation , Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Min-Seuk Lee
- Osulloc Tea R&D Center, Osulloc Farm Corporation , Jeju 699-820, Republic of Korea
| | - Kyeong Hwan Hwang
- Applied Technology & Research Division, R&D Center, AmorePacific Corporation , Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Clara Yongjoo Park
- Division of Food and Nutrition, Chonnam National University , Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea
| | - Eun-Hee Kim
- Protein Structure Group, Korea Basic Science Institute , Cheongwon-Gu, Cheongju-Si, Chungbuk 363-883, Republic of Korea
| | - Jun Seong Park
- Applied Technology & Research Division, R&D Center, AmorePacific Corporation , Yongin-si, Gyeonggi-do 446-729, Republic of Korea
| | - Young-Shick Hong
- Division of Food and Nutrition, Chonnam National University , Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea
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Seluzicki A, Burko Y, Chory J. Dancing in the dark: darkness as a signal in plants. Plant Cell Environ 2017; 40:2487-2501. [PMID: 28044340 PMCID: PMC6110299 DOI: 10.1111/pce.12900] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 05/21/2023]
Abstract
Daily cycles of light and dark provide an organizing principle and temporal constraints under which life on Earth evolved. While light is often the focus of plant studies, it is only half the story. Plants continuously adjust to their surroundings, taking both dawn and dusk as cues to organize their growth, development and metabolism to appropriate times of day. In this review, we examine the effects of darkness on plant physiology and growth. We describe the similarities and differences between seedlings grown in the dark versus those grown in light-dark cycles, and the evolution of etiolated growth. We discuss the integration of the circadian clock into other processes, looking carefully at the points of contact between clock genes and growth-promoting gene-regulatory networks in temporal gating of growth. We also examine daily starch accumulation and degradation, and the possible contribution of dark-specific metabolic controls in regulating energy and growth. Examining these studies together reveals a complex and continuous balancing act, with many signals, dark included, contributing information and guiding the plant through its life cycle. The extraordinary interconnection between light and dark is manifest during cycles of day and night and during seedling emergence above versus below the soil surface.
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Affiliation(s)
- Adam Seluzicki
- Salk Institute for Biological Studies, Plant Biology Laboratory, La Jolla, CA, 92037, USA
| | - Yogev Burko
- Salk Institute for Biological Studies, Plant Biology Laboratory, La Jolla, CA, 92037, USA
- Howard Hughes Medical Institute Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Joanne Chory
- Salk Institute for Biological Studies, Plant Biology Laboratory, La Jolla, CA, 92037, USA
- Howard Hughes Medical Institute Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
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23
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Vieira BC, Bicalho EM, Munné-Bosch S, Garcia QS. Abscisic acid regulates seed germination of Vellozia species in response to temperature. Plant Biol (Stuttg) 2017; 19:211-216. [PMID: 27718313 DOI: 10.1111/plb.12515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 10/04/2016] [Indexed: 05/08/2023]
Abstract
The relationship between the phytohormones, gibberellin (GA) and abscisic acid (ABA) and light and temperature on seed germination is still not well understood. We aimed to investigate the role of the ABA and GA on seed germination of Vellozia caruncularis, V. intermedia and V. alutacea in response to light/dark conditions on different temperature. Seeds were incubated in GA (GA3 or GA4 ) or ABA and their respective biosynthesis inhibitors (paclobutrazol - PAC, and fluridone - FLU) solutions at two contrasting temperatures (25 and 40 °C). Furthermore, endogenous concentrations of active GAs and those of ABA were measured in seeds of V. intermedia and V. alutacea during imbibition/germination. Exogenous ABA inhibited the germination of Vellozia species under all conditions tested. GA, FLU and FLU + GA3 stimulated germination in the dark at 25 °C (GA4 being more effective than GA3 ). PAC reduced seed germination in V. caruncularis and V. alutacea, but did not affect germination of V. intermedia at 40 °C either under light or dark conditions. During imbibition in the dark, levels of active GAs decreased in the seeds of V. intermedia, but were not altered in those of V. alutacea. Incubation at 40 °C decreased ABA levels during imbibition in both V. caruncularis and V. alutacea. We conclude that the seeds of Vellozia species studied here require light or high temperature to germinate and ABA has a major role in the regulation of Vellozia seed germination in response to light and temperature.
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Affiliation(s)
- B C Vieira
- Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - E M Bicalho
- Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - S Munné-Bosch
- Departamento de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Q S Garcia
- Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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24
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Shinskey JL. Sound effects: Multimodal input helps infants find displaced objects. Br J Dev Psychol 2016; 35:317-333. [PMID: 27868211 DOI: 10.1111/bjdp.12165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 08/17/2016] [Indexed: 11/28/2022]
Abstract
Before 9 months, infants use sound to retrieve a stationary object hidden by darkness but not one hidden by occlusion, suggesting auditory input is more salient in the absence of visual input. This article addresses how audiovisual input affects 10-month-olds' search for displaced objects. In AB tasks, infants who previously retrieved an object at A subsequently fail to find it after it is displaced to B, especially following a delay between hiding and retrieval. Experiment 1 manipulated auditory input by keeping the hidden object audible versus silent, and visual input by presenting the delay in the light versus dark. Infants succeeded more at B with audible than silent objects and, unexpectedly, more after delays in the light than dark. Experiment 2 presented both the delay and search phases in darkness. The unexpected light-dark difference disappeared. Across experiments, the presence of auditory input helped infants find displaced objects, whereas the absence of visual input did not. Sound might help by strengthening object representation, reducing memory load, or focusing attention. This work provides new evidence on when bimodal input aids object processing, corroborates claims that audiovisual processing improves over the first year of life, and contributes to multisensory approaches to studying cognition. Statement of contribution What is already known on this subject Before 9 months, infants use sound to retrieve a stationary object hidden by darkness but not one hidden by occlusion. This suggests they find auditory input more salient in the absence of visual input in simple search tasks. After 9 months, infants' object processing appears more sensitive to multimodal (e.g., audiovisual) input. What does this study add? This study tested how audiovisual input affects 10-month-olds' search for an object displaced in an AB task. Sound helped infants find displaced objects in both the presence and absence of visual input. Object processing becomes more sensitive to bimodal input as multisensory functions develop across the first year.
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Affiliation(s)
- Jeanne L Shinskey
- Royal Holloway, University of London, UK.,University of South Carolina, Columbia, South Carolina, USA
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25
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Liebsch D, Keech O. Dark-induced leaf senescence: new insights into a complex light-dependent regulatory pathway. New Phytol 2016; 212:563-570. [PMID: 27716940 DOI: 10.1111/nph.14217] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 07/19/2016] [Indexed: 05/06/2023]
Abstract
563 I. 563 II. 564 III. 564 IV. 565 V. 565 VI. 567 VII. 567 568 References 568 SUMMARY: Leaf senescence - the coordinated, active process leading to the organized dismantling of cellular components to remobilize resources - is a fundamental aspect of plant life. Its tight regulation is essential for plant fitness and has crucial implications for the optimization of plant productivity and storage properties. Various investigations have shown light deprivation and light perception via phytochromes as key elements modulating senescence. However, the signalling pathways linking light deprivation and actual senescence processes have long remained obscure. Recent analyses have demonstrated that PHYTOCHROME-INTERACTING FACTORS (PIFs) are major transcription factors orchestrating dark-induced senescence (DIS) by targeting chloroplast maintenance, chlorophyll metabolism, hormone signalling and production, and the expression of senescence master regulators, uncovering potential molecular links to the energy deprivation signalling pathway. PIF-dependent feed-forward regulatory modules might be of critical importance for the highly complex and initially light-reversible DIS induction.
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Affiliation(s)
- Daniela Liebsch
- Department of Plant Physiology, UPSC, Umeå University, Umeå, S-90187, Sweden
| | - Olivier Keech
- Department of Plant Physiology, UPSC, Umeå University, Umeå, S-90187, Sweden.
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26
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Zeigler-Hill V, McCabe GA, Vrabel JK. The Dark Side of Humor: DSM-5 Pathological Personality Traits and Humor Styles. Eur J Psychol 2016; 12:363-76. [PMID: 27547254 PMCID: PMC4991045 DOI: 10.5964/ejop.v12i3.1109] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 02/14/2016] [Indexed: 11/20/2022]
Abstract
Basic personality traits (e.g., extraversion) have been found to be associated with the humor styles that individuals employ. In the present study, we were interested in determining whether pathological personality traits were also associated with humor styles. We examined the associations between the pathological personality traits captured by the Personality Inventory for the DSM-5 (PID-5) and humor styles in a sample of college students (N = 594). Negative affectivity and detachment were negatively associated with the affiliative and self-enhancing humor styles. Antagonism was positively associated with the aggressive humor style but negatively associated with the affiliative humor style. Disinhibition was positively associated with the aggressive humor style, whereas disinhibition and psychoticism were both positively associated with the self-defeating humor style. Discussion focuses on the implications of these findings and how they can expand our understanding of the connections between the darker aspects of personality and humor.
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Alagöz C, Pekel G, Alagöz N, Sayın N, Yüksel K, Yıldırım Y, Yazıcı AT. Choroidal Thickness, Photoreceptor Thickness, and Retinal Vascular Caliber Alterations in Dark Adaptation. Curr Eye Res 2016; 41:1608-1613. [PMID: 27159535 DOI: 10.3109/02713683.2015.1135961] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
PURPOSE Our aim was to evaluate the alterations of subfoveal choroidal thickness (SFCT), photoreceptor layer thickness (PRT), and retinal vessel diameter in the dark and light adaptation. METHODS Twenty-four eyes of 24 healthy volunteers (12 males, 12 females) were included in this cross-sectional and observational study. The SFCT, PRT, retinal arteriole, and venule caliber measurements were performed with spectral domain optical coherence tomography in the dark (0.0 cd/m2) and under light (80 cd/m2) adapted conditions. RESULTS The mean age of the participants was 30.4 ± 4.4 years (range: 22-42). The SFCT increased statistically significantly in dark adaptation (p < 0.001), then returned to baseline values following light adaptation. The PRT, retinal arteriole, and venule caliber measurements were similar in the dark and light (p > 0.05). CONCLUSIONS While SFCT increased, PRT, and retinal vessel diameter did not change following transition from light to dark.
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Affiliation(s)
- Cengiz Alagöz
- a Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey
| | - Gökhan Pekel
- b Pamukkale University , Ophthalmology Department , Denizli , Turkey
| | - Neşe Alagöz
- a Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey
| | - Nihat Sayın
- c Kanuni Sultan Suleyman Training and Research Hospital, Eye Clinic , Istanbul , Turkey
| | - Kemal Yüksel
- a Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey
| | - Yusuf Yıldırım
- a Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey
| | - Ahmet Taylan Yazıcı
- a Beyoglu Eye Training and Research Hospital, Eye Clinic , Istanbul , Turkey
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28
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Abstract
Purpose To investigate whether retinal vessel calibre measurements on optical retinal photography are affected by light and dark exposure prior to photography and whether the vessel calibre changes during an imaging sequence of several images. Methods Digital optical retinal photographs were obtained from 32 healthy adults in two separate image sequences of six images during 1 min; one sequence with 10 min of dark exposure and one with 10 min of light exposure prior to imaging. Retinal arteriolar and venular calibres were measured computer-assisted and summarized as central retinal artery and vein equivalents (CRAE and CRVE). Outcome measures were difference in calibres after prior light versus prior dark exposure and difference in calibre during each of the two imaging sequences. Results CRVE was wider with prior light exposure (2.7%, p = 0.0001), comparing the first image in each image sequence. Within each sequence, there was a venular dilatation from first to last image, both with prior light exposure (1.7%, p = 0.0003) and prior dark exposure (3.1%, p < 0.0001), with the change less pronounced with prior light exposure (p = 0.0164). CRAE showed no significant change in either outcome. Conclusions Retinal venular calibre was wider with light exposure prior to imaging and increased slightly during the imaging sequences, less pronounced after prior light than dark exposure. Measurement error due to these effects will probably be reduced by avoiding dark prior to imaging, and a possible bias effect of endothelial dysfunction may possibly be reduced by measuring calibre on an image taken early in the image sequence.
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Affiliation(s)
- Therese von Hanno
- Brain and Circulation Research Group, Department of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
- Department of Ophthalmology, Nordland Hospital, Bodø, Norway
| | - Anne Katrin Sjølie
- Brain and Circulation Research Group, Department of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
- Department of Ophthalmology, Odense University Hospital, Odense, Denmark
| | - Ellisiv B. Mathiesen
- Brain and Circulation Research Group, Department of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
- Department of Neurology and Neurophysiology, University Hospital of North Norway, Tromsø, Norway
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29
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Possart A, Fleck C, Hiltbrunner A. Shedding (far-red) light on phytochrome mechanisms and responses in land plants. Plant Sci 2014; 217-218:36-46. [PMID: 24467894 DOI: 10.1016/j.plantsci.2013.11.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 11/20/2013] [Accepted: 11/21/2013] [Indexed: 05/20/2023]
Abstract
In order to monitor ambient light conditions, plants rely on functionally diversified photoreceptors. Among these, phytochromes perceive red (R) and far-red (FR) light. FR light does not constitute a photosynthetic energy source; it however influences adaptive and developmental processes. In seed plants, phytochrome A (phyA) acts as FR receptor and mediates FR high irradiance responses (FR-HIRs). It exerts a dual role by promoting e.g. germination and seedling de-etiolation in canopy shade and by antagonising shade avoidance growth. Even though cryptogam plants such as mosses and ferns do not have phyA, they show FR-induced responses. In the present review we discuss the mechanistic basis of phyA-dependent FR-HIRs as well as their dual role in seed plants. We compare FR responses in seed plants and cryptogam plants and conclude on different potential concepts for the detection of canopy shade. Scenarios for the evolution of FR perception and responses are discussed.
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Affiliation(s)
- Anja Possart
- Center for Plant Molecular Biology, University of Tübingen, 72076 Tübingen, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Christian Fleck
- Laboratory for Systems and Synthetic Biology, Wageningen University, 6703 HB Wageningen, The Netherlands.
| | - Andreas Hiltbrunner
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
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30
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Ruiz-Sola MÁ, Rodríguez-Villalón A, Rodríguez-Concepción M. Light-sensitive Phytochrome-Interacting Factors (PIFs) are not required to regulate phytoene synthase gene expression in the root. Plant Signal Behav 2014; 9:e29248. [PMID: 25763615 PMCID: PMC4203534 DOI: 10.4161/psb.29248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Carotenoids are plastidial isoprenoids essential for the protection of photosynthetic tissues against excess light. They also serve as precursors of apocarotenoid hormones such as abscisic acid (ABA) and strigolactones. The first enzyme of the carotenoid pathway, phytoene synthase (PSY), is also the main rate-limiting step. Unlike that observed in most plants, PSY is encoded by a single gene in Arabidopsis thaliana. Whereas the PSY gene is induced by light in photosynthetic tissues, a root-specific upregulation of PSY expression by salt stress and ABA has been recently demonstrated. Here we report that transcription factors of the Phytochrome-Interacting Factor (PIF) family, previously shown to repress PSY expression in etiolated seedlings and mature leaves, do not influence PSY expression in roots. Together, our results suggest that organ-specific pathways regulate PSY expression and hence carotenoid production in response to different environmental cues.
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31
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Gaston KJ, Bennie J, Davies TW, Hopkins J. The ecological impacts of nighttime light pollution: a mechanistic appraisal. Biol Rev Camb Philos Soc 2013; 88:912-27. [PMID: 23565807 DOI: 10.1111/brv.12036] [Citation(s) in RCA: 430] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 02/16/2013] [Accepted: 02/27/2013] [Indexed: 11/28/2022]
Abstract
The ecological impacts of nighttime light pollution have been a longstanding source of concern, accentuated by realized and projected growth in electrical lighting. As human communities and lighting technologies develop, artificial light increasingly modifies natural light regimes by encroaching on dark refuges in space, in time, and across wavelengths. A wide variety of ecological implications of artificial light have been identified. However, the primary research to date is largely focused on the disruptive influence of nighttime light on higher vertebrates, and while comprehensive reviews have been compiled along taxonomic lines and within specific research domains, the subject is in need of synthesis within a common mechanistic framework. Here we propose such a framework that focuses on the cross-factoring of the ways in which artificial lighting alters natural light regimes (spatially, temporally, and spectrally), and the ways in which light influences biological systems, particularly the distinction between light as a resource and light as an information source. We review the evidence for each of the combinations of this cross-factoring. As artificial lighting alters natural patterns of light in space, time and across wavelengths, natural patterns of resource use and information flows may be disrupted, with downstream effects to the structure and function of ecosystems. This review highlights: (i) the potential influence of nighttime lighting at all levels of biological organisation (from cell to ecosystem); (ii) the significant impact that even low levels of nighttime light pollution can have; and (iii) the existence of major research gaps, particularly in terms of the impacts of light at population and ecosystem levels, identification of intensity thresholds, and the spatial extent of impacts in the vicinity of artificial lights.
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Affiliation(s)
- Kevin J Gaston
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9EZ, U.K
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Zhou X, Jiang Z, Yu D. WRKY22 transcription factor mediates dark-induced leaf senescence in Arabidopsis. Mol Cells 2011; 31:303-13. [PMID: 21359674 PMCID: PMC3933965 DOI: 10.1007/s10059-011-0047-1] [Citation(s) in RCA: 187] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 01/19/2011] [Accepted: 01/21/2011] [Indexed: 01/02/2023] Open
Abstract
Arabidopsis WRKY proteins are plant-specific transcription factors, encoded by a large gene family, which contain the highly conserved amino acid sequence WRKYGQK and the zinc-finger-like motifs, Cys(2)His(2) or Cys(2)HisCys. They can recognize and bind the TTGAC(C/T) W-box ciselements found in the promoters of target genes, and are involved in the regulation of gene expression during pathogen defense, wounding, trichome development, and senescence. Here we investigated the physiological function of the Arabidopsis WRKY22 transcription factor during dark-induced senescence. WRKY22 transcription was suppressed by light and promoted by darkness. In addition, AtWRKY22 expression was markedly induced by H(2)O(2). These results indicated that AtWRKY22 was involved in signal pathways in response to abiotic stress. Dark-treated AtWRKY22 over-expression and knockout lines showed accelerated and delayed senescence phenotypes, respectively, and senescence-associated genes exhibited increased and decreased expression levels. Mutual regulation existed between AtWRKY22 and AtWRKY6, AtWRKY53, and AtWRKY70, respectively. Moreover, AtWRKY22 could influence their relative expression levels by feedback regulation or by other, as yet unknown mechanisms in response to dark. These results prove that AtWRKY22 participates in the dark-induced senescence signal transduction pathway.
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Affiliation(s)
| | - Zhou Jiang
- Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
- Graduate University of Chinese Academy of Sciences, Beijing 100039, China
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Abstract
Short sleep/dark durations, due to late bedtimes or early wake times or both, are common in modern society. We have previously shown that a series of days with a late bedtime phase delays the human dim light melatonin rhythm, as compared to a series of days with an early bedtime, despite a fixed wake time. Here we compared the effect of an early versus late wake time with a fixed bedtime on the human dim light melatonin rhythm. Fourteen healthy subjects experienced 2 weeks of short 6h nights with an early wake time fixed at their habitual weekday wake time and 2 weeks of long 9 h nights with a wake time that occurred 3h later than the early wake time, in counterbalanced order. We found that after 2 weeks with the late wake time, the dim light melatonin onset delayed by 2.4 h and the dim light melatonin offset delayed by 2.6 h (both p < 0.001), as compared to after 2 weeks with the early wake time. These results highlight the substantial influence that wake time, likely via the associated morning light exposure, has on the timing of the human circadian clock. Furthermore, the results suggest that when people truncate their sleep by waking early their circadian clocks phase advance and when people wake late their circadian clocks phase delay.
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Affiliation(s)
- Helen J Burgess
- Biological Rhythms Research Laboratory, Department of Behavioral Sciences, Rush University Medical Center, 1645 W. Jackson Blvd, Suite 425, Chicago, IL 60612, USA.
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Abstract
• The ability of the diatom Thalassiosira weissflogii to assimilate inorganic N in darkness is compared with that seen in flagellates. • Experiments were conducted with T. weissflogii grown in N-replete and in N-limiting cultures and the rates and capacity for ammonium and nitrate assimilation were determined. • High daily growth rates in the diatom under high-light nitrate-replete conditions are only attainable by continuing nitrate assimilation in darkness using excess C accumulated in the light when nitrate assimilation cannot match C-fixation. The ability to use ammonium in darkness is greater than for nitrate but the ratio of dark to light assimilation for each N source is similar over a wide range of cellular N : C ratios. These capabilities are in strong contrast with those in the flagellates Heterosigma carterae and Heterocapsa illdefina, which are incapable of high nitrate use in darkness. • While the possession of large capacity for dark nitrate-assimilation in diatoms may provide a mechanism that overcomes nitrate limitation of growth, the explanation for the lower capabilities exhibited by flagellates is less clear.
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Affiliation(s)
- Darren R Clark
- Ecology Research Unit, School of Biological Sciences, University of Wales Swansea, Swansea SA2 8PP, UK
| | - Kevin J Flynn
- Ecology Research Unit, School of Biological Sciences, University of Wales Swansea, Swansea SA2 8PP, UK
| | - Nicholas J P Owens
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth PL1 3DH, UK
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Flynn KJ, Clark DR, Owens NJP. Modelling suggests that optimization of dark nitrogen-assimilation need not be a critical selective feature in phytoplankton. New Phytol 2002; 155:109-119. [PMID: 33873301 DOI: 10.1046/j.1469-8137.2002.00436.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• Alternative strategies for the dark assimilation of ammonium and nitrate into microalgae are explored using a mechanistic model of algal physiology. • The standard diatom strategy, continuation of N assimilation at high rates in darkness as long as reserve C remains, is the most advantageous. The flagellate strategy, incorporating ammonium but not nitrate at a reasonable rate in darkness, is best suited to organisms with high metabolic costs, inhabiting waters with relatively high concentrations of ammonium. The strategy of vertically migrating diatoms - accumulation of nitrate in internal pools for assimilation after return to the photic zone - is best suited to slow-growing cells in low-ammonium environments. • Differences between the strategies become less significant with increasing N-source limitation (the situation more typically encountered by flagellates and migratory species) because transport rather than post-transport assimilatory processes become most limiting. • It is suggested that optimization of dark N-assimilation is not a critical selective feature; organisms with contrasting abilities in this regard usually inhabit different water bodies and have other more fundamental phenotypic differences (e.g. motility or silicon requirements).
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Affiliation(s)
- Kevin J Flynn
- Ecology Research Unit, School of Biological Sciences, University of Wales Swansea, Swansea SA2 8PP, UK
| | - Darren R Clark
- Ecology Research Unit, School of Biological Sciences, University of Wales Swansea, Swansea SA2 8PP, UK
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36
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Colussi PA, Quinn LM, Huang DC, Coombe M, Read SH, Richardson H, Kumar S. Debcl, a proapoptotic Bcl-2 homologue, is a component of the Drosophila melanogaster cell death machinery. J Cell Biol 2000; 148:703-14. [PMID: 10684252 PMCID: PMC2169366 DOI: 10.1083/jcb.148.4.703] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bcl-2 family of proteins are key regulators of apoptosis. Both proapoptotic and antiapoptotic members of this family are found in mammalian cells, but no such proteins have been described in insects. Here, we report the identification and characterization of Debcl, the first Bcl-2 homologue in Drosophila melanogaster. Structurally, Debcl is similar to Bax-like proapoptotic Bcl-2 family members. Ectopic expression of Debcl in cultured cells and in transgenic flies causes apoptosis, which is inhibited by coexpression of the baculovirus caspase inhibitor P35, indicating that Debcl is a proapoptotic protein that functions in a caspase-dependent manner. debcl expression correlates with developmental cell death in specific Drosophila tissues. We also show that debcl genetically interacts with diap1 and dark, and that debcl-mediated apoptosis is not affected by gene dosage of rpr, hid, and grim. Biochemically, Debcl can interact with several mammalian and viral prosurvival Bcl-2 family members, but not with the proapoptotic members, suggesting that it may regulate apoptosis by antagonizing prosurvival Bcl-2 proteins. RNA interference studies indicate that Debcl is required for developmental apoptosis in Drosophila embryos. These results suggest that the main components of the mammalian apoptosis machinery are conserved in insects.
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MESH Headings
- Amino Acid Sequence
- Animals
- Animals, Genetically Modified
- Apoptosis/drug effects
- Apoptosis/genetics
- Apoptosis/physiology
- Caspase Inhibitors
- Caspases/metabolism
- Cell Survival/drug effects
- Cells, Cultured
- Cloning, Molecular
- Drosophila Proteins
- Drosophila melanogaster/cytology
- Drosophila melanogaster/embryology
- Drosophila melanogaster/genetics
- Drosophila melanogaster/metabolism
- Epistasis, Genetic
- Gene Expression
- Genes, Insect/genetics
- Inhibitor of Apoptosis Proteins
- Insect Proteins/genetics
- Molecular Sequence Data
- Mutation/genetics
- Protein Binding
- Protein Structure, Tertiary
- Proteins/genetics
- Proto-Oncogene Proteins c-bcl-2/chemistry
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- RNA, Double-Stranded/administration & dosage
- RNA, Double-Stranded/pharmacology
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Sequence Homology, Amino Acid
- Viral Proteins/genetics
- Viral Proteins/metabolism
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Affiliation(s)
- Paul A. Colussi
- The Hanson Centre for Cancer Research, Institute of Medical and Veterinary Science, Adelaide, SA 5000, Australia
| | - Leonie M. Quinn
- Department of Genetics, The University of Adelaide, Adelaide, SA 5001, Australia
| | - David C.S. Huang
- The Walter and Eliza Hall Institute of Medical Research, The Royal Melbourne Hospital, Melbourne, Vic 3050, Australia
| | - Michelle Coombe
- Department of Genetics, The University of Adelaide, Adelaide, SA 5001, Australia
| | - Stuart H. Read
- The Hanson Centre for Cancer Research, Institute of Medical and Veterinary Science, Adelaide, SA 5000, Australia
| | - Helena Richardson
- Department of Genetics, The University of Adelaide, Adelaide, SA 5001, Australia
| | - Sharad Kumar
- The Hanson Centre for Cancer Research, Institute of Medical and Veterinary Science, Adelaide, SA 5000, Australia
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