Bücher und Buchkapitel
Möller, B.; Bürstenbinder, K. Semi-Automatic Cell Segmentation from Noisy Image Data for Quantification of Microtubule Organization on Single Cell Level 199-203, (2019) ISBN: 978-1-5386-3640-4 DOI: 10.1109/ISBI.2019.8759145
The structure of the microtubule cytoskeleton
provides valuable information related to morphogenesis of cells. The
cytoskeleton organizes into diverse patterns that vary in cells of
different types and tissues, but also within a single tissue. To assess
differences in cytoskeleton organization methods are needed that
quantify cytoskeleton patterns within a complete cell and which are
suitable for large data sets. A major bottleneck in most approaches,
however, is a lack of techniques for automatic extraction of cell
contours. Here, we present a semi-automatic pipeline for cell
segmentation and quantification of microtubule organization. Automatic
methods are applied to extract major parts of the contours and a handy
image editor is provided to manually add missing information
efficiently. Experimental results prove that our approach yields
high-quality contour data with minimal user intervention and serves a
suitable basis for subsequent quantitative studies.
Bücher und Buchkapitel
Flores, R.; Gago-Zachert, S.; De la Peña, M.; Navarro, B. Chrysanthemum Chlorotic Mottle Viroid (Ed. A. Hadidi, et al.). 331-338, (2017) ISBN: eBook ISBN: 9780128017029; Hardcover ISBN: 9780128014981. DOI: 10.1016/B978-0-12-801498-1.00031-0
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Bücher und Buchkapitel
Jasmonic acid and other fatty-acid-derived compounds called oxylipins are signals in stress responses and development of plants. The receptor complex, signal transduction components as well as repressors and activators in jasmonate-induced gene expression have been elucidated. Different regulatory levels and cross-talk with other hormones are responsible for the multiplicity of plant responses to environmental and developmental cues.
Bücher und Buchkapitel
Tissier, A.; Ziegler, J.; Vogt, T. Specialized Plant Metabolites: Diversity and Biosynthesis (Krauss, G.-J. & Nies, D. H., eds.). 14-37, (2015) ISBN: 978-3-527-31650-2 DOI: 10.1002/9783527686063.ch2
Plant secondary metabolites, also termed
specialized plant metabolites, currently comprise more than 200 000
natural products that are all based on a few biosynthetic pathways and
key primary metabolites. Some pathways like flavonoid and terpenoid
biosynthesis are universally distributed in the plant kingdom, whereas
others like alkaloid or cyanogenic glycoside biosynthesis are restricted
to a limited set of taxa. Diversification is achieved by an array of
mechanisms at the genetic and enzymatic level including gene
duplications, substrate promiscuity of enzymes, cell‐specific regulatory
systems, together with modularity and combinatorial aspects.
Specialized metabolites reflect adaptations to a specific environment.
The observed diversity illustrates the heterogeneity and multitude of
ecological habitats and niches that plants have colonized so far and
constitutes a reservoir of potential new metabolites that may provide
adaptive advantage in the face of environmental changes. The code that
connects the observed chemical diversity to this ecological diversity is
largely unknown. One way to apprehend this diversity is to realize its
tremendous plasticity and evolutionary potential. This chapter presents
an overview of the most widespread and popular secondary metabolites,
which provide a definite advantage to adapt to or to colonize a
particular environment, making the boundary between the “primary” and
the “secondary” old fashioned and blurry.
Publikation
Guseman, J. M.; Hellmuth, A.; Lanctot, A.; Feldman, T. P.; Moss, B. L.; Klavins, E.; Calderón Villalobos, L. I. A.; Nemhauser, J. L. Auxin-induced degradation dynamics set the pace for lateral root development Development 142, 1-5, (2015) DOI: 10.1242/dev.117234
Auxin elicits diverse cell behaviors through a simple nuclear signaling pathway initiated by degradation of Aux/IAA co-repressors. Our previous work revealed that members of the large Arabidopsis Aux/IAA family exhibit a range of degradation rates in synthetic contexts. However, it remained an unresolved issue whether differences in Aux/IAA turnover rates played a significant role in plant responses to auxin. Here, we use the well-established model of lateral root development to directly test the hypothesis that the rate of auxin-induced Aux/IAA turnover sets the pace for auxin-regulated developmental events. We did this by generating transgenic plants expressing degradation rate variants of IAA14, a crucial determinant of lateral root initiation. Progression through the well-established stages of lateral root development was strongly correlated with the engineered rates of IAA14 turnover, leading to the conclusion that Aux/IAAs are auxin-initiated timers that synchronize developmental transitions
Bücher und Buchkapitel
Wasternack, C. Jasmonates in plant growth and stress responses. (Tran, L.-S.; Pal, S.). Springer, 221-264, (2014) ISBN: 978-1-4939-0490-7 (hardcover) 978-1-4939-4814-7 (softcover) DOI: 10.1007/978-1-4939-0491-4_8
Abiotic and biotic stresses adversely affect plant growth and productivity. The phytohormones regulate key physiological events under normal and stressful conditions for plant development. Accumulative research efforts have discovered important roles of phytohormones and their interactions in regulation of plant adaptation to numerous stressors. Intensive molecular studies have elucidated various plant hormonal pathways; each of which consist of many signaling components that link a specific hormone perception to the regulation of downstream genes. Signal transduction pathways of auxin, abscisic acid, cytokinins, gibberellins and ethylene have been thoroughly investigated. More recently, emerging signaling pathways of brassinosteroids, jasmonates, salicylic acid and strigolactones offer an exciting gateway for understanding their multiple roles in plant physiological processes.At the molecular level, phytohormonal crosstalks can be antagonistic or synergistic or additive in actions. Additionally, the signal transduction component(s) of one hormonal pathway may interplay with the signaling component(s) of other hormonal pathway(s). Together these and other research findings have revolutionized the concept of phytohormonal studies in plants. Importantly, genetic engineering now enables plant biologists to manipulate the signaling pathways of plant hormones for development of crop varieties with improved yield and stress tolerance.This book, written by internationally recognized scholars from various countries, represents the state-of-the-art understanding of plant hormones’ biology, signal transduction and implications. Aimed at a wide range of readers, including researchers, students, teachers and many others who have interests in this flourishing research field, every section is concluded with biotechnological strategies to modulate hormone contents or signal transduction pathways and crosstalk that enable us to develop crops in a sustainable manner. Given the important physiological implications of plant hormones in stressful environments, our book is finalized with chapters on phytohormonal crosstalks under abiotic and biotic stresses.
Publikation
Delker, C.; Sonntag, L.; Geo, V. J.; Janitza, P.; Ibañez, C.; Ziermann, H.; Peterson, T.; Denk, K.; Mull, S.; Ziegler, J.; Davis, S. J.; Schneeberger, K.; Quint, M. The DET1-COP1-HY5 Pathway Constitutes a Multipurpose Signaling Module Regulating Plant Photomorphogenesis and Thermomorphogenesis Cell Rep 9, 1983–1989, (2014) DOI: 10.1016/j.celrep.2014.11.043
Developmental plasticity enables plants to respond to elevated ambient temperatures by adapting their shoot architecture. On the cellular level, the basic-helix-loop-helix (bHLH) transcription factor PHYTOCHROME INTERACTING FACTOR 4 (PIF4) coordinates this response by activating hormonal modules that in turn regulate growth. In addition to an unknown temperature-sensing mechanism, it is currently not understood how temperature regulates PIF4 activity. Using a forward genetic approach in Arabidopsis thaliana, we present extensive genetic evidence demonstrating that the DE-ETIOLATED 1 (DET1)-CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1)-ELONGATED HYPOCOTYL 5 (HY5)-dependent photomorphogenesis pathway transcriptionally regulates PIF4 to coordinate seedling growth in response to elevated temperature. Our findings demonstrate that two of the most prevalent environmental cues, light and temperature, share a much larger set of signaling components than previously assumed. Similar to the toolbox concept in animal embryonic patterning, multipurpose signaling modules might have evolved in plants to translate various environmental stimuli into adaptational growth processes
Bücher und Buchkapitel
Vaira, A. M.; Gago-Zachert, S.; Garcia, M. L.; Guerri, J.; Hammond, J.; Milne, R. G.; Moreno, P.; Morikawa, T.; Natsuaki, T.; Navarro, J. A.; Pallas, V.; Torok, V.; Verbeek, M.; Vetten, H. J. Family - Ophioviridae (King, A. M. Q., et al., eds.). 743-748, (2012) ISBN: 978-0-12-384684-6 DOI: 10.1016/B978-0-12-384684-6.00060-4
This chapter focuses on Ophioviridae family whose
sole member genus is Ophiovirus. The member species of the genus include
Citrus psorosis virus (CPsV), Freesia sneak virus(FreSV), Lettuce ring
necrosis virus (LRNV), and Mirafiori lettuce big-vein virus (MiLBVV).The
single stranded negative/possibly ambisense RNA genome is divided into
3–4 segments, each of which is encapsidated in a single coat protein
(43–50 kDa) forming filamentous virions of about 3 nm in diameter, in
shape of kinked or probably internally coiled circles of at least two
different contour lengths. Ophioviruses can be mechanically transmitted
to a limited range of test plants, inducing local lesions and systemic
mottle. The natural hosts of CPsV, ranunculus white mottle virus (RWMV),
MiLBVV, and LRNV are dicotyledonous plants of widely differing
taxonomy. CPsV has a wide geographical distribution in citrus in the
Americas, in the Mediterranean and in New Zealand. FreSV has been
reported in two species of the family Ranunculacae from Northern Italy,
and in lettuce in France and Germany. Tulip mild mottle mosaic virus
(TMMMV) has been reported in tulips in Japan. LRNV is closely associated
with lettuce ring necrosis disease in The Netherlands, Belgium, and
France, and FreSV has been reported in Europe, Africa, North America and
New Zealand.
Publikation
Costa, C. T.; Strieder, M. L.; Abel, S.; Delatorre, C. A. Phosphorus and nitrogen interaction: loss of QC identity in response to P or N limitation is antecipated in pdr23 mutant Braz J Plant Physiol 23, 219-229, (2011) DOI: 10.1590/S1677-04202011000300006
Changes in root architecture are an important
adaptive strategy used by plants in response to limited nutrient
availability to increase the odds of acquiring them. The quiescent
center (QC) plays an important role by altering the meristem activity
causing differentiation and therefore, inducing a determinate growth
program. The arabidopsis mutant pdr23 presents primary short root in the
presence of nitrate and is inefficient in the use of nucleic acids as a
source of phosphorus. In this study the effect of the pdr23 mutation on
the QC maintenance under low phosphorus (P) and/or nitrogen is
evaluated. QC identity is maintained in wild-type in the absence of
nitrate and/or phosphate if nucleic acids can be used as an alternative
source of these nutrients, but not in pdr23. The mutant is not able to
use nucleic acids efficiently for substitute Pi, determinate growth is
observed, similar to wild-type in the total absence of P. In the absence
of N pdr23 loses the expression of QC identity marker earlier than
wild-type, indicating that not only the response to P is altered, but
also to N. The data suggest that the mutation affects a gene involved
either in the crosstalk between these nutrients or in a pathway shared
by both nutrients limitation response. Moreover loss of QC identity is
also observed in wild-type in the absence of N at longer limitation.
Less drastic symptoms are observed in lateral roots of both genotypes.
Bücher und Buchkapitel
Dorka, R.; Miersch, O.; Hause, B.; Weik, P.; Wasternack, C. Chronobiologische Phänomene und Jasmonatgehalt bei Viscum album L. (Scheer, R.; Bauer, R.; Bekker, A.; Berg, P. A.; Fintelmann, V.). 49-56, (2009) ISBN: 978-3-933351-82
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