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https://www.readbyqxmd.com/read/27925396/arabidopsis-sumo-protease-asp1-positively-regulates-flowering-time-partially-through-regulating-flc-stability
#1
Xiangxiong Kong, Xi Luo, Gao-Ping Qu, Peng Liu, Jing Bo Jin
The initiation of flowering is tightly regulated by the endogenous and environment signals, which is crucial for the reproductive success of flowering plants. It is well known that autonomous and vernalization pathways repress transcription of FLOWERING LOCUS C (FLC), a focal floral repressor, but how its protein stability is regulated remains largely unknown. Here, we found that mutations in a novel Arabidopsis SUMO protease 1 (ASP1) resulted in a strong late-flowering phenotype under long-days, but to a lesser extent under short-days...
December 7, 2016: Journal of Integrative Plant Biology
https://www.readbyqxmd.com/read/27925178/adaptive-patterns-of-phenotypic-plasticity-in-laboratory-and-field-environments-in-drosophila-melanogaster
#2
Vinayak Mathur, Paul S Schmidt
Identifying mechanisms of adaptation to variable environments is essential in developing a comprehensive understanding of evolutionary dynamics in natural populations. Phenotypic plasticity allows for phenotypic change in response to changes in the environment, and as such may play a major role in adaptation to environmental heterogeneity. Here, the plasticity of stress response in D. melanogaster originating from two distinct geographic regions and ecological habitats was examined. Adults were given a short-term, 5-day exposure to combinations of temperature and photoperiod to elicit a plastic response for three fundamental aspects of stress tolerance that vary adaptively with geography...
December 7, 2016: Evolution; International Journal of Organic Evolution
https://www.readbyqxmd.com/read/27920193/light-intensity-of-5-or-20%C3%A2-lux-on-broiler-behavior-welfare-and-productivity
#3
Jean-Loup Rault, Katie Clark, Peter J Groves, Greg M Cronin
Light intensity can influence broiler behavior, but discrepancies in the scientific literature remain. Furthermore, few studies have investigated the welfare implications induced by varying light intensity. We investigated the effects of providing 5 or 20 lux light intensity on broiler behavior, welfare and productivity. A total of 1,872 Ross 308 broilers of mixed sex were studied across 2 replicates. Treatments began on d 8 with one of 2 light intensity levels: 5 lux or 20 lux, using LED lights on a 16L:8D photoperiod with 30 min sunrise and sunset periods...
December 5, 2016: Poultry Science
https://www.readbyqxmd.com/read/27918538/variation-in-the-flowering-gene-self-pruning-5g-promotes-day-neutrality-and-early-yield-in-tomato
#4
Sebastian Soyk, Niels A Müller, Soon Ju Park, Inga Schmalenbach, Ke Jiang, Ryosuke Hayama, Lei Zhang, Joyce Van Eck, José M Jiménez-Gómez, Zachary B Lippman
Plants evolved so that their flowering is triggered by seasonal changes in day length. However, day-length sensitivity in crops limits their geographical range of cultivation, and thus modification of the photoperiod response was critical for their domestication. Here we show that loss of day-length-sensitive flowering in tomato was driven by the florigen paralog and flowering repressor SELF-PRUNING 5G (SP5G). SP5G expression is induced to high levels during long days in wild species, but not in cultivated tomato because of cis-regulatory variation...
December 5, 2016: Nature Genetics
https://www.readbyqxmd.com/read/27916575/circannual-and-circadian-rhythms-of-hypothalamic-dna-methyltransferase-and-histone-deacetylase-expression-in-male-siberian-hamsters-phodopus-sungorus
#5
Tyler J Stevenson
Precise timing of gene transcription is a fundamental component of many biological rhythms. DNA methylation and histone acetylation are two epigenetic modifications that can affect the probability of gene transcription and RNA expression. Enzymes involved in DNA methylation (dnmts) have been shown to exhibit photoperiodic rhythms in expression in the hypothalamus, which coincide with hypothalamic expression of deiodinase type III (dio3), a gene involved in the photoperiodic regulation of reproduction. It is currently unknown whether enzymes involved in histone deacetylation (hdacs) also vary in response to photoperiod, nor have seasonal changes in the circadian waveforms of methylation and/or acetylation enzymes been examined...
December 1, 2016: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/27912863/circadian-rhythm-and-sleep-during-prolonged-antarctic-residence-at-chinese-zhongshan-station
#6
Nan Chen, Quan Wu, Yanlei Xiong, Guang Chen, Dandan Song, Chengli Xu
OBJECTIVE: Residence at Zhongshan Station (69°22'24″S, 76°22'40″E) for over 1 year exposes winter-over members to marked changes of light-dark cycle, ranging from the constant daylight of polar days to the constant darkness of polar nights, in addition to geographic and social isolation. This extreme photoperiodic environment may increase the risk of sleep disturbances and circadian desynchrony. The aim of this study was to investigate the circadian rhythm and sleep phase of Chinese winter-over expeditioners at Zhongshan Station...
December 2016: Wilderness & Environmental Medicine
https://www.readbyqxmd.com/read/27901351/biosynthesis-of-gonadotropin-releasing-hormone-gnrh-and-gnrh-receptor-gnrhr-in-hypothalamic-pituitary-unit-of-anoestrous-and-cyclic-ewes
#7
M O Ciechanowska, M Łapot, K Mateusiak, E Paruszewska, T Malewski, F Przekop
This study was performed to explain how the molecular processes governing the biosynthesis of gonadotropin-releasing hormone (GnRH) and GnRH receptor (GnRHR) in the hypothalamic-pituitary unit are reflected by luteinizing hormone (LH) secretion in sheep during anoestrous period and during luteal and follicular phases of the oestrous cycle. Using an enzyme-linked immunosorbent assay (ELISA), we analyzed the levels of GnRH and GnRHR in preoptic area (POA), anterior (AH) and ventromedial hypothalamus (VM), stalk-median eminence (SME), and GnRHR in the anterior pituitary gland (AP)...
November 30, 2016: Canadian Journal of Physiology and Pharmacology
https://www.readbyqxmd.com/read/27901272/photoperiod-and-temperature-mediated-control-of-phenology-in-trees-a-molecular-perspective
#8
REVIEW
Rajesh Kumar Singh, Tetiana Svystun, Badr AlDahmash, Anna Maria Jönsson, Rishikesh P Bhalerao
Contents I. II. III. IV. V. VI. VII. VIII. Acknowledgements References SUMMARY: Trees growing in boreal and temperate regions synchronize their growth with seasonal climatic changes in adaptive responses that are essential for their survival. These trees cease growth before the winter and establish a dormant state during which growth cessation is maintained by repression of responses to growth-promotive signals. Reactivation of growth in the spring follows the release from dormancy promoted by prolonged exposure to low temperature during the winter...
November 30, 2016: New Phytologist
https://www.readbyqxmd.com/read/27900827/the-role-of-latitudinal-genetic-and-temperature-variation-in-the-induction-of-diapause-of-papilio-glaucus-lepidoptera-papilionidae
#9
Sean F Ryan, Patti Valella, Gabrielle Thivierge, Matthew L Aardema, J Mark Scriber
A key adaptation in insects for dealing with variable environmental conditions is the ability to diapause. The tiger swallowtail butterflies, Papilio glaucus and P. canadensis are ideal species to explore the genetic causes and population genetic consequences of diapause because divergence in this trait is believed to be a salient factor in maintaining a hybrid zone between these species. Yet little is known about the factors that influence diapause induction in this system. Here we explored how spatial (latitudinal), environmental (temperature) and genetic (hybridization) factors affect diapause induction in this system...
November 29, 2016: Insect Science
https://www.readbyqxmd.com/read/27899931/melatonin-in-plants-and-plant-culture-systems-variability-stability-and-efficient-quantification
#10
Lauren A E Erland, Abhishek Chattopadhyay, Andrew Maxwell P Jones, Praveen K Saxena
Despite growing evidence of the importance of melatonin and serotonin in the plant life, there is still much debate over the stability of melatonin, with extraction and analysis methods varying greatly from lab to lab with respect to time, temperature, light levels, extraction solvents, and mechanical disruption. The variability in methodology has created conflicting results that confound the comparison of studies to determine the role of melatonin in plant physiology. We here describe a fully validated method for the quantification of melatonin, serotonin and their biosynthetic precursors: tryptophan, tryptamine and N-acetylserotonin by liquid chromatography single quadrupole mass spectrometry (LC-MS) in diverse plant species and tissues...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27898828/population-structure-in-the-model-grass-is-highly-correlated-with-flowering-differences-across-broad-geographic-areas
#11
Ludmila Tyler, Scott J Lee, Nelson D Young, Gregory A DeIulio, Elena Benavente, Michael Reagon, Jessica Sysopha, Riccardo M Baldini, Angelo Troìa, Samuel P Hazen, Ana L Caicedo
The small, annual grass (L.) Beauv., a close relative of wheat ( L.) and barley ( L.), is a powerful model system for cereals and bioenergy grasses. Genome-wide association studies (GWAS) of natural variation can elucidate the genetic basis of complex traits but have been so far limited in by the lack of large numbers of well-characterized and sufficiently diverse accessions. Here, we report on genotyping-by-sequencing (GBS) of 84 , seven , and three accessions with diverse geographic origins including Albania, Armenia, Georgia, Italy, Spain, and Turkey...
July 2016: Plant Genome
https://www.readbyqxmd.com/read/27890022/continuous-light-after-2-months-of-long-days-stimulates-ram-testis-volume-and-increases-fertility-in-spring
#12
D Chesneau, D Guillaume, P Chemineau, B Malpaux
Seasonal reproduction is one of the major biotechnical and economic constraints of sheep production in temperate latitudes. Treatments using extra light followed by melatonin implants have been used satisfactorily in open barns, farms and artificial insemination centres to produce out-of-season sexual activity in rams. The aim of the present study is to explore the possibility of replacing melatonin implants with continuous light (LL), which was recently shown to increase LH secretion similar to melatonin and/or pinealectomy...
November 28, 2016: Animal: An International Journal of Animal Bioscience
https://www.readbyqxmd.com/read/27885421/role-of-vernalization-mediated-demethylation-in-the-floral-transition-of-brassica-rapa
#13
Weike Duan, Huijun Zhang, Bei Zhang, Xiaoting Wu, Shuaixu Shao, Ying Li, Xilin Hou, Tongkun Liu
Vernalization-mediated demethylation of BrCKA2 (casein kinase II α-subunit) and BrCKB4 (casein kinase II β-subunit) shorten the period of the clock gene BrCCA1 (circadian clock associated 1) in Brassica rapa. Photoperiod and vernalization are two environmental cues involved in the regulation of floral transition, but the ways in which they interact remain unclear. DNA methylation is one of the main mechanisms involved in controlling the functional state of chromatin and gene expression in response to environmental signals...
November 24, 2016: Planta
https://www.readbyqxmd.com/read/27874965/somatostatin-agonist-pasireotide-inhibits-exercise-stimulated-growth-in-the-male-siberian-hamster-phodopus-sungorus
#14
Rebecca Dumbell, Ines Petri, Frank Scherbarth, Victoria Diedrich, Herbert A Schmid, Stephan Steinlechner, Perry Barrett
The Siberian hamster (Phodopus sungorus) is a seasonal mammal, exhibiting a suite of physiologically and behaviourally distinct traits dependent on the time of year and governed by changes in perceived day length (photoperiod). These attributes include significant weight loss, reduced food intake, gonadal atrophy, and pelage change with short day photoperiod as in winter. The central mechanisms driving seasonal phenotype change during winter are mediated by a reduced availability of hypothalamic tri-iodothyronine (T3), but downstream mechanisms responsible for physiological and behavioural changes are yet to be fully elucidated...
November 22, 2016: Journal of Neuroendocrinology
https://www.readbyqxmd.com/read/27868159/are-aphid-parasitoids-from-mild-winter-climates-losing-their-winter-diapause
#15
Kévin Tougeron, Cécile Le Lann, Jacques Brodeur, Joan van Baaren
Temperature is both a selective pressure and a modulator of the diapause expression in insects from temperate regions. Thus, with climate warming, an alteration of the response to seasonal changes is expected, either through genetic adaptations to novel climatic conditions or phenotypic plasticity. Since the 1980s in western France, the winter guild of aphid parasitoids (Hymenoptera: Braconidae) in cereal fields has been made up of two species: Aphidius rhopalosiphi and Aphidius matricariae. The recent activity of two other species, Aphidius avenae and Aphidius ervi, during the winter months suggests that a modification of aphid parasitoid overwintering strategies has taken place within the guild...
November 21, 2016: Oecologia
https://www.readbyqxmd.com/read/27867253/drosophila-ezoana-uses-an-hour-glass-or-highly-damped-circadian-clock-for-measuring-night-length-and-inducing-diapause
#16
Koustubh M Vaze, Charlotte Helfrich-Förster
Insects inhabiting the temperate zones measure seasonal changes in day or night length to enter the overwintering diapause. Diapause induction occurs after the duration of the night exceeds a critical night length (CNL). Our understanding of the time measurement mechanisms is continuously evolving subsequent to Bünning's proposal that circadian systems play the clock role in photoperiodic time measurement (Bünning, 1936). Initially, the photoperiodic clocks were considered to be either based on circadian oscillators or on simple hour-glasses, depending on 'positive' or 'negative' responses in Nanda-Hamner and Bünsow experiments (Nanda & Hammer, 1958; Bünsow, 1960)...
December 2016: Physiological Entomology
https://www.readbyqxmd.com/read/27864513/construction-of-a-male-sterility-system-for-hybrid-rice-breeding-and-seed-production-using-a-nuclear-male-sterility-gene
#17
Zhenyi Chang, Zhufeng Chen, Na Wang, Gang Xie, Jiawei Lu, Wei Yan, Junli Zhou, Xiaoyan Tang, Xing Wang Deng
The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks...
December 6, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27862517/clock-gene-polymorphism-migratory-behaviour-and-geographic-distribution-a-comparative-study-of-trans-saharan-migratory-birds
#18
Gaia Bazzi, Jacopo G Cecere, Manuela Caprioli, Emanuele Gatti, Luca Gianfranceschi, Stefano Podofillini, Cristina D Possenti, Roberto Ambrosini, Nicola Saino, Fernando Spina, Diego Rubolini
Migratory behaviour is controlled by endogenous circannual rhythms that are synchronized by external cues, such as photoperiod. Investigations on the genetic basis of circannual rhythmicity in vertebrates have highlighted that variation at candidate 'circadian clock' genes may play a major role in regulating photoperiodic responses and timing of life cycle events, such as reproduction and migration. In this comparative study of 23 trans-Saharan migratory bird species, we investigated the relationships between species-level genetic variation at two candidate genes, Clock and Adcyap1, and species' traits related to migration and geographic distribution, including timing of spring migration across the Mediterranean Sea, migration distance and breeding latitude...
November 14, 2016: Molecular Ecology
https://www.readbyqxmd.com/read/27854155/photoperiod-response-and-floral-transition-in-sorghum
#19
Tezera W Wolabu, Million Tadege
Sorghum is a short day plant with strong photoperiod response and its cultivation for grain in temperate regions necessitated the development of photoperiod insensitive mutants that can flower rapidly in the long days of summer. Wild type genotypes grow vegetatively in summer accumulating significant biomass before floral transition ensues during the shorter days of fall. Thus, photoperiod insensitive mutants are grown for grain production while photoperiod sensitive wild type genotypes are grown for forage and biomass feedstock production in the United States...
November 17, 2016: Plant Signaling & Behavior
https://www.readbyqxmd.com/read/27852950/photoperiod-affects-the-phenotype-of-mitochondrial-complex-i-mutants
#20
Pierre Pétriacq, Linda De Bont, Lucie Genestout, Jingfang Hao, Constance Laureau, Igor Florez-Sarasa, Touami Rzigui, Guillaume Queval, Françoise Gilard, Caroline Mauve, Florence Guérard, Marlène Lamothe-Sibold, Jessica Marion, Chantal Fresneau, Spencer Craig Brown, Antoine Danon, Anja Krieger-Liszkay, Richard Berthomé, Miquel Ribas-Carbo, Guillaume G B Tcherkez, Gabriel Cornic, Bernard Pineau, Bertrand Gakiere, Rosine De Paepe
Plant mutants for genes encoding subunits of mitochondrial Complex I (CI, NADH:ubiquinone oxidoreductase), the first enzyme of the respiratory chain, display various phenotypes depending on growth conditions. Here, we examined the impact of photoperiod, a major environmental factor controlling plant development, on two Arabidopsis thaliana CI mutants: a new insertion mutant interrupted in both ndufs8.1 and ndufs8.2 genes encoding the NDUFS8 subunit, and the previously characterized ndufs4 CI mutant. In long day (LD) condition, both ndufs8...
November 16, 2016: Plant Physiology
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