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https://www.readbyqxmd.com/read/28732144/influence-of-high-latitude-light-conditions-on-sensory-quality-and-contents-of-health-and-sensory-related-compounds-in-swede-roots-brassica-napus-l-ssp-rapifera-metzg
#1
Jørgen A B Mølmann, Sidsel Fiskaa Hagen, Gunnar B Bengtsson, Tor J Johansen
BACKGROUND: Vegetable growers in Arctic areas usually must rely on market strategies based on regional origin and product quality. Swede roots (rutabaga) were grown in a phytotron to investigate the effect of high latitude light conditions on sensory quality and some health and sensory-related compounds. Experimental treatments included modifications of 24 h natural day length (69° 39' N), by moving plants at daily intervals to dark chambers with either no light, fluorescent growth light and/or low intensity photoperiod extension...
July 21, 2017: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/28732105/shining-a-light-on-the-arabidopsis-circadian-clock
#2
REVIEW
Rachael J Oakenfull, Seth J Davis
The circadian clock provides essential timing information to ensure optimal growth to prevailing external environmental conditions. A major time-setting mechanism (zeitgeber) in clock synchronisation is light. Differing light wavelengths, intensities and photoperiodic duration are processed for the clock-setting mechanism. Many studies on light-input pathways to the clock have focused on Arabidopsis thaliana. Photoreceptors are specific chromic proteins that detect light signals and transmit this information to the central circadian oscillator through a number of different signalling mechanisms...
July 21, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28731219/daylight-effect-on-melatonin-secretion-in-adult-female-guanacos-lama-guanicoe
#3
J L Riveros, L M Correa, G Schuler
The wild South American camelids developed a strategy of seasonal reproduction during spring and summer with singleton birth. The photoperiod is one of the factors that may modulate this seasonality where light would be translated into a hormonal signal. This study evaluated the influence of changes in daily light intensity on melatonin concentration in captive guanacos under a long-day photoperiod (16 hr light/8 hr dark; 33 '28'S). Mean melatonin concentration was 28.3 ± 20.3 pg/ml, with a maximum of 52...
July 21, 2017: Reproduction in Domestic Animals, Zuchthygiene
https://www.readbyqxmd.com/read/28729868/the-c4-model-grass-setaria-is-a-short-day-plant-with-secondary-long-day-genetic-regulation
#4
Andrew N Doust, Margarita Mauro-Herrera, John G Hodge, Jessica Stromski
The effect of photoperiod (day:night ratio) on flowering time was investigated in the wild species, Setaria viridis, and in a set of recombinant inbred lines (RILs) derived from a cross between foxtail millet (S. italica) and its wild ancestor green foxtail (S. viridis). Photoperiods totaled 24 h, with three trials of 8:16, 12:12 and 16:8 light:dark hour regimes for the RIL population, and these plus 10:14 and 14:10 for the experiments with S. viridis alone. The response of S. viridis to light intensity as well as photoperiod was assessed by duplicating photoperiods at two light intensities (300 and 600 μmol...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28729527/comparative-transcriptome-analysis-of-the-floral-transition-in-rosa-chinensis-old-blush-and-r-odorata-var-gigantea
#5
Xuelian Guo, Chao Yu, Le Luo, Huihua Wan, Yushu Li, Jia Wang, Tangren Cheng, Huitang Pan, Qixiang Zhang
The floral transition is a crucial developmental event, but little is known about the underlying regulatory networks in seasonally and continuously flowering roses. In this study, we compared the genetic basis of flowering in two rose species, Rosa chinensis 'Old Blush', which flowers continuously, and R. odorata var. gigantea, which blooms in early spring. Gene ontology (GO) terms related to methylation, light reaction, and starch metabolism were enriched in R. odorata var. gigantea and terms associated with sugar metabolism were enriched in R...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28729017/daily-levels-and-rhythm-in-circulating-corticosterone-and-insulin-are-altered-with-photostimulated-seasonal-states-in-night-migratory-blackheaded-buntings
#6
Ila Mishra, Devraj Singh, Vinod Kumar
The circadian rhythms are involved in the photostimulation of seasonal responses in migratory blackheaded buntings. Here, we investigated whether changes in daily levels and rhythm in corticosterone (cort) and insulin secretions were associated with transitions in the photoperiodic seasonal states. Buntings were exposed to short days to maintain the winter (photosensitive) non-migratory state, and to long days for varying durations to induce the premigratory, migratory (shown by migratory restlessness at night, Zugunruhe) and summer non-migratory (photorefractory) states...
July 17, 2017: Hormones and Behavior
https://www.readbyqxmd.com/read/28728370/endotoxin-induced-inflammation-disturbs-melatonin-secretion-in-ewe
#7
Andrzej Przemysław Herman, Karolina Wojtulewicz, Joanna Bochenek, Agata Krawczyńska, Hanna Antushevich, Bartosz Pawlina, Marlena Zielińska-Góska, Anna Herman, Katarzyna Romanowicz, Dorota Tomaszewska-Zaremba
The study was designed to determine the effect of intravenous administration of bacterial endotoxin - lipopolysaccharide (LPS) - on the nocturnal secretion of melatonin and on the expression of enzymes of the melatonin biosynthetic pathway in the pineal gland of ewes, taking into account two different photoperiodic conditions: short night (SN; n = 12) and long night (LN; n = 12). Endotoxin administration lowered (P < 0.05) levels of circulating melatonin in animals from LN photoperiod only during the first hour after treatment, while in ewes from SN photoperiod only in the third hour after the injection...
June 27, 2017: Asian-Australasian Journal of Animal Sciences
https://www.readbyqxmd.com/read/28726096/identification-and-characterization-of-the-flower-meristem-identity-gene-mhylfy-in-mycoheterotrophic-plant-monotropa-hypopitys
#8
A V Shchennikova, O A Shulga, A V Beletsky, M A Filyushin, E Z Kochieva, N V Ravin, K G Skryabin
The gene encoding the transcription factor LEAFY was identified in the genome of the mycoheterotrophic plant, pinesap Monotropa hypopitys. In the transcriptomes of roots, bracts, and flowers of flowering pinesaps, the MhyLFY gene expression was absent. These data suggest the conservativeness of the LFY-dependent mechanism of flower meristem identity and flower formation in heterotrophic species with some differences associated to the specificity of development and the structure of such plants. The pinesap flowering under the control of the transcription factor MhyLFY may be initiated either in an embryonic inflorescence during spring dormancy release of adventitious root buds or in an inflorescence of a growing reproductive stem after photoperiodic induction...
May 2017: Doklady. Biochemistry and Biophysics
https://www.readbyqxmd.com/read/28722229/a-transposon-directed-epigenetic-change-in-zmcct-underlies-quantitative-resistance-to-gibberella-stalk-rot-in-maize
#9
Chao Wang, Qin Yang, Weixiang Wang, Yipu Li, Yanling Guo, Dongfeng Zhang, Xuena Ma, Wei Song, Jiuran Zhao, Mingliang Xu
A major resistance quantitative trait locus, qRfg1, significantly enhances maize resistance to Gibberella stalk rot, a devastating disease caused by Fusarium graminearum. However, the underlying molecular mechanism remains unknown. We adopted a map-based cloning approach to identify the resistance gene at qRfg1 and examined the dynamic epigenetic changes during qRfg1-mediated maize resistance to the disease. A CCT domain-containing gene, ZmCCT, is the causal gene at the qRfg1 locus and a polymorphic CACTA-like transposable element (TE1) c...
July 19, 2017: New Phytologist
https://www.readbyqxmd.com/read/28720705/conceptual-framework-of-the-eco-physiological-phases-of-insect-diapause-development-justified-by-transcriptomic-profiling
#10
Vladimír Koštál, Tomáš Štětina, Rodolphe Poupardin, Jaroslava Korbelová, Alexander William Bruce
Insects often overcome unfavorable seasons in a hormonally regulated state of diapause during which their activity ceases, development is arrested, metabolic rate is suppressed, and tolerance of environmental stress is bolstered. Diapausing insects pass through a stereotypic succession of eco-physiological phases termed "diapause development." The phasing is varied in the literature, and the whole concept is sometimes criticized as being too artificial. Here we present the results of transcriptional profiling using custom microarrays representing 1,042 genes in the drosophilid fly, Chymomyza costata Fully grown, third-instar larvae programmed for diapause by a photoperiodic (short-day) signal were assayed as they traversed the diapause developmental program...
July 18, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28716942/maternal-photoperiod-programs-hypothalamic-thyroid-status-via-the-fetal-pituitary-gland
#11
Cristina Sáenz de Miera, Béatrice Bothorel, Catherine Jaeger, Valérie Simonneaux, David Hazlerigg
In wild mammals, offspring development must anticipate forthcoming metabolic demands and opportunities. Within species, different developmental strategies may be used, dependent on when in the year conception takes place. This phenotypic flexibility is initiated before birth and is linked to the pattern of day length (photoperiod) exposure experienced by the mother during pregnancy. This programming depends on transplacental communication via the pineal hormone melatonin. Here, we show that, in the Siberian hamster (Phodopus sungorus), the programming effect of melatonin is mediated by the pars tuberalis (PT) of the fetal pituitary gland, before the fetal circadian system and autonomous melatonin production is established...
July 17, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28710485/alternative-functions-of-hd1-in-repressing-or-promoting-heading-are-determined-by-ghd7-status-under-long-day-conditions
#12
Zhanyi Zhang, Wei Hu, Guojing Shen, Haiyang Liu, Yong Hu, Xiangchun Zhou, Touming Liu, Yongzhong Xing
Previous studies suggested that Hd1 promoted heading under short-day conditions (SD) and delayed heading under long-day conditions (LD). However in this study, Hd1 was demonstrated to consistently promote heading date in Zhenshan 97 (ZS97) background by upregulating Ehd1, Hd3a and RFT1 expression under both SD and LD. While the high photoperiod sensitivity of Hd1 was observed in Minghui 63 (MH63) background, with heading being suppressed in LD but promoted in SD. Comparative analysis of two sets of near isogenic lines of Hd1 in MH63 and ZS97 backgrounds indicated that the alternative functions of Hd1 in promoting or suppressing heading under LD are dependent on the previously cloned flowering repressor gene Ghd7...
July 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28709398/cannibalism-and-activity-rate-in-larval-damselflies-increase-along-a-latitudinal-gradient-as-a-consequence-of-time-constraints
#13
Szymon Sniegula, Maria J Golab, Frank Johansson
BACKGROUND: Predation is ubiquitous in nature. One form of predation is cannibalism, which is affected by many factors such as size structure and resource density. However, cannibalism may also be influenced by abiotic factors such as seasonal time constraints. Since time constraints are greater at high latitudes, cannibalism could be stronger at such latitudes, but we know next to nothing about latitudinal variation in cannibalism. In this study, we examined cannibalism and activity in larvae of the damselfly Lestes sponsa along a latitudinal gradient across Europe...
July 14, 2017: BMC Evolutionary Biology
https://www.readbyqxmd.com/read/28708527/artificially-extended-photoperiod-administered-to-pre-partum-mares-via-blue-light-to-a-single-eye-observations-on-gestation-length-foal-birth-weight-and-foal-hair-coat-at-birth
#14
Margaret B Nolan, Caroline M Walsh, Noelle Duff, Conor McCrarren, Ralph L Prendergast, Barbara A Murphy
In seasonally breeding animals, photoperiod perception is crucial for timing of important physiological events. In the horse, long day photoperiod influences the onset of ovulation and cyclicity, shedding of the heavier winter coat and the timing of parturition. In this compilation of studies, conducted across three breeding seasons and two countries, the impact of artificially extended day length was investigated on gestation length, foal birth weight and foal hair coat at birth. The light therapy was administered to pre-partum mares via mobile head worn masks which provided short wavelength blue light to a single eye...
June 9, 2017: Theriogenology
https://www.readbyqxmd.com/read/28708495/genome-wide-association-studies-for-reproductive-seasonality-traits-in-rasa-aragonesa-sheep-breed
#15
Albert Martinez-Royo, José Luis Alabart, Pilar Sarto, Magdalena Serrano, Belén Lahoz, José Folch, Jorge Hugo Calvo
Sheep breeds from Mediterranean area show reproductive seasonal patterns of oestrous behaviour and ovulatory activity, mainly regulated by variation in the photoperiod. Maximal reproductive activity is associated with short days from August to March. The aim of this study therefore was, to identify new SNPs and genes associated to reproductive seasonality in sheep by using the Illumina OvineSNP50 Beadchip. A total of 239 adult Rasa Aragonesa breed ewes from one flock were controlled from January to August. Three reproductive seasonality traits were considered: the total days of anoestrus (TDA), based on weekly individual plasma progesterone levels and defined as the sum of days in anoestrus, considering anoestrus those periods with three or more consecutive P4 concentrations lower than 0...
May 19, 2017: Theriogenology
https://www.readbyqxmd.com/read/28708429/effects-of-altered-photoperiod-on-circadian-clock-and-lipid-metabolism-in-rats
#16
Xiaoxian Xie, Binggong Zhao, Liangfeng Huang, Qichen Shen, Lingyan Ma, Yangyang Chen, Tao Wu, Zhengwei Fu
Disruption of circadian clock timekeeping due to changes in the photoperiod enhances the risk of lipid metabolism disorders and metabolic syndrome. However, the effects of altered photoperiods on the circadian clock and lipid metabolism are not well understood. To explore the effects of altered photoperiods, we developed a rat model where rats were exposed to either short-day or long-day conditions. Our findings demonstrated that altered photoperiods mediated circadian clocks by partly disrupting rhythmicity and shifting phase values of clock genes...
July 14, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28707275/vanilla-vanilla-planifolia-jacks-cell-suspension-cultures-establishment-characterization-and-applications
#17
Marco A Ramírez-Mosqueda, Lourdes G Iglesias-Andreu
The establishment and characterization of cell suspension cultures are an in vitro culture technique very useful for various plant biotechnological applications (production of secondary metabolites, mass micropropagation, protoplast isolation and fusion, gene transfer and the investigation of cell pathways). The objective of this study was to establish and characterization of cell suspension cultures of V. planifolia by inducing friable calluses. For that, friable calluses were obtained from immature seeds cultivated in MS medium supplemented with 0...
August 2017: 3 Biotech
https://www.readbyqxmd.com/read/28696547/heat-stress-in-pregnant-sows-thermal-responses-and-subsequent-performance-of-sows-and-their-offspring
#18
REVIEW
Matthew C Lucy, Timothy J Safranski
Seasonal infertility is a significant problem in the swine industry, and may be influenced by photoperiod and heat stress. Heat stress during gestation in particular affects pregnancy, resulting in long-term developmental damage to the offspring. This review summarizes what is known about how heat stress on the pregnant sow affects lactation and her offspring. Sows responded to heat stress during gestation with increased rectal temperature, respiration rate, and skin temperature, and tended to reduce their activity-which may have changed their body composition, increasing the adipose-to-muscle ratio...
July 11, 2017: Molecular Reproduction and Development
https://www.readbyqxmd.com/read/28694155/denervation-as-a-tool-for-testing-sympathetic-control-of-white-adipose-tissue
#19
REVIEW
Ruth B S Harris
This review summarizes the evidence derived from studies utilizing denervation procedures to demonstrate sympathetic control of white adipose tissue metabolism and body fat mass. A majority of the work demonstrating neural control of white fat was performed in the Bartness laboratory with Siberian hamsters as the predominant experimental model. These animals experience dramatic changes in body fat mass in response to changes in photoperiod, however, the mechanisms identified in hamsters have been reproduced or further elucidated by experiments with other animal models...
July 7, 2017: Physiology & Behavior
https://www.readbyqxmd.com/read/28694154/short-photoperiod-reverses-obesity-in-siberian-hamsters-via-sympathetically-induced-lipolysis-and-browning-in-adipose-tissue
#20
REVIEW
Vitaly Ryu, Eleen Zarebidaki, H Elliott Albers, Bingzhong Xue, Timothy J Bartness
Changes in photoperiod length are transduced into neuroendocrine signals by melatonin (MEL) secreted by the pineal gland triggering seasonally adaptive responses in many animal species. Siberian hamsters, transferred from a long-day 'summer-like' photoperiod (LD) to a short-day 'winter-like' photoperiod (SD), exhibit a naturally-occurring reversal in obesity. Photoperiod-induced changes in adiposity are mediated by the duration of MEL secretion and can be mimicked by exogenously administered MEL into animals housed in LD...
July 7, 2017: Physiology & Behavior
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