Feasibility and Participants' Satisfaction

The Internet-based psychotherapeutic intervention Onco-STEP for adolescent and young adult (AYA)-aged survivors of pediatric cancer was developed, implemented, and participants' satisfaction was evaluated by use of questionnaires. The intervention consisted of two modules: “Looking Back,” aimed to reduce posttraumatic stress symptoms, and “Looking Ahead,” supported coping with cancer-related fears of relapse and progression. The writing program was fully completed by 20 participants (Mage=27.3±4.8 years at study; 70% female). The majority was satisfied and perceived the treatment components as helpful. Results demonstrate that an Internet-based psychotherapeutic intervention for AYA-aged survivors of pediatric cancer is feasible and accepted by the target population

Kinetic Characterisation of a Single Chain Antibody against the Hormone Abscisic Acid: Comparison with Its Parental Monoclonal

A single-chain Fv fragment antibody (scFv) specific for the plant hormone abscisic acid (ABA) has been expressed in the bacterium Escherichia coli as a fusion protein. The kinetics of ABA binding have been measured using surface plasmon resonance spectrometry (BIAcore 2000) using surface and solution assays. Care was taken to calculate the concentration of active protein in each sample using initial rate measurements under conditions of partial mass transport limitation. The fusion product, parental monoclonal antibody and the free scFv all have low nanomolar affinity constants, but there is a lower dissociation rate constant for the parental monoclonal resulting in a three-fold greater affinity. Analogue specificity was tested and structure-activity binding preferences measured. The biologically-active (+)-ABA enantiomer is recognised with an affinity three orders of magnitude higher than the inactive (-)-ABA. Metabolites of ABA including phaseic acid, dihydrophaseic acid and deoxy-ABA have affinities over 100-fold lower than that for (+)-ABA. These properties of the scFv make it suitable as a sensor domain in bioreporters specific for the naturally occurring form of ABA

Professional football players as immaterial assets

Die bilanzielle Behandlung eines Profifußballspielers ist – obwohl es sich dabei in der Praxis um den wichtigsten Vermögenswert der Fußballclubs handelt – in wissenschaftlichen Auseinandersetzungen bisher nur fragmentarisch behandelt worden. Die nachfolgende Arbeit stellt deshalb, die verschiedenen Regelungskonzepte der Rechnungslegung vor und untersucht die gegebenen Besonderheiten, die sich mit Blick auf die bilanzielle Behandlung eines Profispielers ergeben. Daneben werden die verschiedenen Bewertungsverfahren untersucht, die zur Bestimmung des tatsächlichen Werts eines Profifußballspielers herangezogen werden können. Im Anschluss daran wird anhand einer kurzen empirischen Untersuchung veranschaulicht, dass die insoweit bestehenden Bewertungsverfahren nicht in der Lage sind, den tatsächlichen Wert eines Profifußballspielers zutreffend wiederzugeben. Abschließend werden deshalb Empfehlungen ausgesprochen, wie mit diesem Befund in der täglichen Praxis umzugehen ist

Probing the in situ volumes of Arabidopsis leaf plastids using three‐dimensional confocal and scanning electron microscopy

Leaf plastids harbor a plethora of biochemical reactions including photosynthesis, one of the most important metabolic pathways on Earth. Scientists are eager to unveil the physiological processes within the organelle but also their interconnection with the rest of the plant cell. An increasingly important feature of this venture is to use experimental data in the design of metabolic models. A remaining obstacle has been the limited in situ volume information of plastids and other cell organelles. To fill this gap for chloroplasts, we established three microscopy protocols delivering in situ volumes based on: (i) chlorophyll fluorescence emerging from the thylakoid membrane, (ii) a CFP marker embedded in the envelope, and (iii) calculations from serial block-face scanning electron microscopy (SBFSEM). The obtained data were corroborated by comparing wild-type data with two mutant lines affected in the plastid division machinery known to produce small and large mesophyll chloroplasts, respectively. Furthermore, we also determined the volume of the much smaller guard cell plastids. Interestingly, their volume is not governed by the same components of the division machinery which defines mesophyll plastid size. Based on our three approaches, the average volume of a mature Col-0 wild-type mesophyll chloroplasts is 93 μm3. Wild-type guard cell plastids are approximately 18 μm3. Lastly, our comparative analysis shows that the chlorophyll fluorescence analysis can accurately determine chloroplast volumes, providing an important tool to research groups without access to transgenic marker lines expressing genetically encoded fluorescence proteins or costly SBFSEM equipment

A chloroplast retrograde signal, 3’phosphoadenosine 5’-phosphate, acts as a secondary messenger in abscisic acid signaling in stomatal closure and germination

Organelle-nuclear retrograde signaling regulates gene expression, but its roles in specialized cells and integration with hormonal signaling remain enigmatic. Here we show that the SAL1-PAP (3'-phosphoadenosine 5'- phosphate) retrograde pathway interacts with abscisic acid (ABA) signaling to regulate stomatal closure and seed germination in Arabidopsis. Genetically or exogenously manipulating PAP bypasses the canonical signaling components ABA Insensitive 1 (ABI1) and Open Stomata 1 (OST1); priming an alternative pathway that restores ABA-responsive gene expression, ROS bursts, ion channel function, stomatal closure and drought tolerance in ost1-2. PAP also inhibits wild type and abi1-1 seed germination by enhancing ABA sensitivity. PAP-XRN signaling interacts with ABA, ROS and Ca2+; up-regulating multiple ABA signaling components, including lowly-expressed Calcium Dependent Protein Kinases (CDPKs) capable of activating the anion channel SLAC1. Thus, PAP exhibits many secondary messenger attributes and exemplifies how retrograde signals can have broader roles in hormone signaling, allowing chloroplasts to fine-tune physiological responses.Wannarat Pornsiriwong, Gonzalo M Estavillo, Kai Xun Chan, Estee E Tee, Diep Ganguly, Peter A Crisp, Su Yin Phua, Chenchen Zhao, Jiaen Qiu, Jiyoung Park, Miing Tiem Yong, Nazia Nisar, Arun Kumar Yadav, Benjamin Schwessinger, John Rathjen, Christopher I Cazzonelli, Philippa B Wilson, Matthew Gilliham, Zhong-Hua Chen, Barry J Pogso

Compact groups with a dense free abelian subgroup

The compact groups having a dense infinite cyclic subgroup (known as monothetic compact groups) have been studied by many authors for their relevance and nice applications. In this paper we describe in full details the compact groups $K$ with a dense free abelian subgroup $F$ and we describe the minimum rank $r_t(K)$ of such a subgroup $F$ of $K$. Surprisingly, it is either finite or coincides with the density character $d(K)$ of $K$.

A fluorescent hormone biosensor reveals the dynamics of jasmonate signalling in plants

Activated forms of jasmonic acid (JA) are central signals coordinating plant responses to stresses, yet tools to analyse their spatial and temporal distribution are lacking. Here we describe a JA perception biosensor termed Jas9-VENUS that allows the quantification of dynamic changes in JA distribution in response to stress with high spatiotemporal sensitivity. We show that Jas9-VENUS abundance is dependent on bioactive JA isoforms, the COI1 co-receptor, a functional Jas motif and proteasome activity. We demonstrate the utility of Jas9-VENUS to analyse responses to JA in planta at a cellular scale, both quantitatively and dynamically. This included using Jas9-VENUS to determine the cotyledon-to-root JA signal velocities on wounding, revealing two distinct phases of JA activity in the root. Our results demonstrate the value of developing quantitative sensors such as Jas9-VENUS to provide high-resolution spatiotemporal data about hormone distribution in response to plant abiotic and biotic stresses

Genetically Encoded Biosensors in Plants: Pathways to Discovery.

Genetically encoded biosensors that directly interact with a molecule of interest were first introduced more than 20 years ago with fusion proteins that served as fluorescent indicators for calcium ions. Since then, the technology has matured into a diverse array of biosensors that have been deployed to improve our spatiotemporal understanding of molecules whose dynamics have profound influence on plant physiology and development. In this review, we address several types of biosensors with a focus on genetically encoded calcium indicators, which are now the most diverse and advanced group of biosensors. We then consider the discoveries in plant biology made by using biosensors for calcium, pH, reactive oxygen species, redox conditions, primary metabolites, phytohormones, and nutrients. These discoveries were dependent on the engineering, characterization, and optimization required to develop a successful biosensor; they were also dependent on the methodological developments required to express, detect, and analyze the readout of such biosensors.Gatsby Research Fellowship awarded to A.M.J

Making microscopy count: quantitative light microscopy of dynamic processes in living plants

First published: April 2016This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Cell theory has officially reached 350 years of age as the first use of the word ‘cell’ in a biological context can be traced to a description of plant material by Robert Hooke in his historic publication “Micrographia: or some physiological definitions of minute bodies”. The 2015 Royal Microscopical Society Botanical Microscopy meeting was a celebration of the streams of investigation initiated by Hooke to understand at the sub-cellular scale how plant cell function and form arises. Much of the work presented, and Honorary Fellowships awarded, reflected the advanced application of bioimaging informatics to extract quantitative data from micrographs that reveal dynamic molecular processes driving cell growth and physiology. The field has progressed from collecting many pixels in multiple modes to associating these measurements with objects or features that are meaningful biologically. The additional complexity involves object identification that draws on a different type of expertise from computer science and statistics that is often impenetrable to biologists. There are many useful tools and approaches being developed, but we now need more inter-disciplinary exchange to use them effectively. In this review we show how this quiet revolution has provided tools available to any personal computer user. We also discuss the oft-neglected issue of quantifying algorithm robustness and the exciting possibilities offered through the integration of physiological information generated by biosensors with object detection and tracking

Plant Immune Memory in Systemic Tissue Does Not Involve Changes in Rapid Calcium Signaling

Upon pathogen recognition, a transient rise in cytoplasmic calcium levels is one of the earliest events in plants and a prerequisite for defense initiation and signal propagation from a local site to systemic plant tissues. However, it is unclear if calcium signaling differs in the context of priming: Do plants exposed to a first pathogen stimulus and have consequently established systemic acquired resistance (SAR) display altered calcium responses to a second pathogen stimulus? Several calcium indicator systems including aequorin, YC3.6 or R-GECO1 have been used to document local calcium responses to the bacterial flg22 peptide but systemic calcium imaging within a single plant remains a technical challenge. Here, we report on an experimental approach to monitor flg22-induced calcium responses in systemic leaves of primed plants. The calcium-dependent protein kinase CPK5 is a key calcium sensor and regulator of the NADPH oxidase RBOHD and plays a role in the systemic calcium-ROS signal propagation. We therefore compared flg22-induced cytoplasmic calcium changes in Arabidopsis wild-type, cpk5 mutant and CPK5-overexpressing plants (exhibiting constitutive priming) by introgressing the calcium indicator R-GECO1-mTurquoise that allows internal normalization through mTurquoise fluorescence. Aequorin-based analyses were included for comparison. Based on the R-GECO1-mTurquoise data, CPK5-OE appears to reinforce an “oscillatory-like” Ca2+ signature in flg22-treated local tissues. However, no change was observed in the flg22-induced calcium response in the systemic tissues of plants that had been pre-challenged by a priming stimulus – neither in wild-type nor in cpk5 or CPK5-OE-lines. These data indicate that the mechanistic manifestation of a plant immune memory in distal plant parts required for enhanced pathogen resistance does not include changes in rapid calcium signaling upstream of CPK5 but rather relies on downstream defense responses