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This article discusses the potential positive and problematic influences of the National Early Literacy Panel (NELP; 2008) report on prekindergarten and kindergarten classroom instructional practice. The authors support the instructional importance of the majority of the foundational skills identified in the NELP report as having "clear and consistently strong relationships with later conventional literacy skills" but also detail a number of concerns about NELP-influenced instructional recommendations drawn to date, arguing that the NELP report is both insufficiently clear and overly narrow with respect to what preschool teachers should be focusing on instructionally in early literacy. [ABSTRACT FROM AUTHOR]

Multiple theoretical perspectives are employed in the analysis of interviews and written reflections from pre-service teachers who used web-based video cases in their literacy methods courses. The four theoretical perspectives: Transformational, Transactional, Deictic, and Critical illuminate the multiple and complementary aspects of pre-service teachers' interactions with the web-based video cases. Findings are presented in four categories: 1) Patterns in Case Use; 2) Patterns of Transaction; 3) Patterns in Conceptions about Literacy/Technology Convergence; and 4) Issues of Equity and Access. Implications related to the intersection of web-based video case technology, literacy, and teacher education are drawn for literacy professors, researchers, and literacy teacher education. [ABSTRACT FROM AUTHOR]

The plant hormone auxin has long been known to play a crucial role in plant growth and development, but how it affects so many different processes has remained a mystery. Recent evidence from genetic and molecular studies has begun to reveal a possible mechanism for auxin action. In this article we will present an overview with specific emphasis on auxin's role in roots ofArabidopsis thaliana, focusing on cell division, elongation and differentiation. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various articles within the issue on topics including literacy research and practice, correlation between fluency skills and comprehension skills, and phonics and phonemic awareness.

Summary: An environmentally responsive root system is crucial for plant growth and crop yield, especially in suboptimal soil conditions. This responsiveness enables the plant to exploit regions of high nutrient density while simultaneously minimizing abiotic stress. Despite the vital importance of root systems in regulating plant growth, significant gaps of knowledge exist in the mechanisms that regulate their architecture.Auxin defines both the frequency of lateral root (LR) initiation and the rate of LR outgrowth. Here, we describe a search for proteins that regulate root system architecture (RSA) by interacting directly with a key auxin transporter, PIN1. The native separation of Arabidopsis plasma membrane protein complexes identified several PIN1 co‐purifying proteins.Among them, AZG1 was subsequently confirmed as a PIN1 interactor. Here, we show that, in Arabidopsis, AZG1 is a cytokinin (CK) import protein that co‐localizes with and stabilizes PIN1, linking auxin and CK transport streams. AZG1 expression in LR primordia is sensitive to NaCl, and the frequency of LRs is AZG1‐dependent under salt stress.This report therefore identifies a potential point for auxin:cytokinin crosstalk, which shapes RSA in response to NaCl. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of seating arrangements and duration of the read-aloud activity on student engagement during read-alouds in preschool classroom. Topics include a rationale for considering student engagement for effective read-alouds, a study of the relationship between student engagement and seating arrangement and duration, and other factors affecting engagement such as the content of book and individual characteristics of students.

Describes two projects that incorporated inquiry and technology into urban educational settings. Details on inquiry-based learning and how it functions as a literary program; Facets of inquiry-based teaching; Role of technology as cognitive support for inquiry; Lessons learned about inquiry, literacy and technology.

The article offers the author's insights related to literacy policy. Topics discussed include the need for literacy educator develop policy among young people as emphasized by the International Literacy Association, three literacy policy briefs of the Center for Literacy at the University of Illinois at Chicago (UIC) such as Early Childhood, Digital Literacies, and Common Core State Standards, and four topics for policy actions such as curriculum, teacher preparation, and school leadership.

Apple (Malusxdomestica Borkh) fruits are stored for long periods of time at low temperatures (1 °C) leading to the occurrence of physiological disorders. 'Superficial scald' of Granny Smith apples, an economically important ethylene-dependent disorder, was used as a model to study relationships among ethylene action, the regulation of the ROP-GAP rheostat, and maintenance of H2O2 homeostasis in fruits during prolonged cold exposure. The ROP-GAP rheostat is a key module for adaptation to low oxygen in Arabidopsis through Respiratory Burst NADPH Oxidase Homologs (RBOH)-mediated and ROP GTPase-dependent regulation of reactive oxygen species (ROS) homeostasis. Here, it was shown that the transcriptional expression of several components of the apple ROP-GAP machinery, including genes encoding RBOHs, ROPs, and their ancillary proteins ROP-GEFs and ROP-GAPs, is coordinately and negatively regulated by ethylene in conjunction with the progressive impairment of apoplastic H2O2 homeostatic levels. RNA sequencing analyses showed that several components of the known ROP- and ROS-associated transcriptional networks are regulated along with the ROP-GAP rheostat in response to ethylene perception. These findings may extend the role of the ROP-GAP rheostat beyond hypoxic responses and suggest that it may be a functional regulatory node involved in the integration of ethylene and ROS signalling pathways in abiotic stress. [ABSTRACT FROM AUTHOR]

Glutathione is involved in thiol redox signaling and acts as a major redox buffer against reactive oxygen species, helping to maintain a reducing environment in vivo. Glutathione reductase (GR) catalyzes the reduction of glutathione disulfide (GSSG) into reduced glutathione (GSH). The Arabidopsis thaliana genome encodes two GRs : GR1 and GR2. Whereas the cytosolic/peroxisomal GR1 is not crucial for plant development, we show here that the plastid-localized GR2 is essential for root growth and root apical meristem (RAM) maintenance. We identify a GR2 mutant, miao , that displays strong inhibition of root growth and severe defects in the RAM , with GR activity being reduced to ∼50%. miao accumulates high levels of GSSG and exhibits increased glutathione oxidation. The exogenous application of GSH or the thiol-reducing agent DTT can rescue the root phenotype of miao , demonstrating that the RAM defects in miao are triggered by glutathione oxidation. Our in silico analysis of public microarray data shows that auxin and glutathione redox signaling generally act independently at the transcriptional level. We propose that glutathione redox status is essential for RAM maintenance through both auxin/PLETHORA (PLT)-dependent and auxin/PLT-independent redox signaling pathways. [ABSTRACT FROM AUTHOR]

Local efflux-dependent auxin gradients and maxima mediate organ and tissue development in plants. Auxin efflux is regulated by dynamic expression and subcellular localization of the PIN auxin-efflux proteins, which appears to be established not only through a self-organizing auxin-mediated polarization mechanism, but also through other means, such as cell fate determination and auxin-independent mechanisms. Here, we show that the Arabidopsis thaliana NO VEIN (NOV) gene, encoding a novel, plant-specific nuclear factor, is required for leaf vascular development, cellular patterning and stem cell maintenance in the root meristem, as well as for cotyledon outgrowth and separation, nov mutations affect many aspects of auxin-dependent development without directly affecting auxin perception. NOV is required for provascular PIN1 expression and region-specific expression of PIN7 in leaf primordia, cell type-specific expression of PIN3, PIN4, and PIN7 in the root, and PIN2 polarity in the root cortex. NOV is specifically expressed in developing embryos, leaf primordia, and shoot and root apical meristems. Our data suggest that NOV function underlies cell fate decisions associated with auxin gradients and maxima, thus establishing cell type-specific PIN expression and polarity. We propose that NOV mediates the acquisition of competence to undergo auxin-dependent coordinated cell specification and patterning, thereby eliciting context-dependent auxin-mediated developmental responses. [ABSTRACT FROM AUTHOR]

C4 photosynthesis increases the efficiency of carbon fixation by spatially separating high concentrations of molecular oxygen from Rubisco. The specialized leaf anatomy required for this separation evolved independently many times. The morphology of C4 root systems is also distinctive and adapted to support high rates of photosynthesis; however, little is known about the molecular mechanisms that have driven the evolution of C4 root system architecture. Using a mutant screen in the C4 model plant Setaria italica, we identify Siaux1-1 and Siaux1-2 as root system architecture mutants. Unlike in S. viridis, AUX1 promotes lateral root development in S. italica. A cell by cell analysis of the Siaux1-1 root apical meristem revealed changes in the distribution of cell volumes in all cell layers and a dependence of the frequency of protophloem and protoxylem strands on SiAUX1. We explore the molecular basis of the role of SiAUX1 in seedling development using an RNAseq analysis of wild-type and Siaux1-1 plants and present novel targets for SiAUX1-dependent gene regulation. Using a selection sweep and haplotype analysis of SiAUX1, we show that Hap-2412TT in the promoter region of SiAUX1 is an allele which is associated with lateral root number and has been strongly selected for during Setaria domestication., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

The transport of auxin controls the rate, direction and localization of plant growth and development. The course of auxin transport is defined by the polar subcellular localization of the PIN proteins, a family of auxin efflux transporters. However, little is known about the composition and regulation of the PIN protein complex. Here, using blue-native PAGE and quantitative mass spectrometry, we identify native PIN core transport units as homo- and heteromers assembled from PIN1, PIN2, PIN3, PIN4 and PIN7 subunits only. Furthermore, we show that endogenous flavonols stabilize PIN dimers to regulate auxin efflux in the same way as does the auxin transport inhibitor 1-naphthylphthalamic acid (NPA). This inhibitory mechanism is counteracted both by the natural auxin indole-3-acetic acid and by phosphomimetic amino acids introduced into the PIN1 cytoplasmic domain. Our results lend mechanistic insights into an endogenous control mechanism which regulates PIN function and opens the way for a deeper understanding of the protein environment and regulation of the polar auxin transport complex., (© 2020 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)

Our current understanding of how plants move auxin through their tissues is largely built on the use of polar auxin transporter inhibitors. Although the most important proteins that mediate auxin transport and its regulation have probably all been identified and the mapping of their interactions is well underway, mechanistically we are still surprisingly far away from understanding how auxin is transported. Such an understanding will only emerge after new data are placed in the context of the wealth of physiological data on which they are founded. This review will look back over the use of a key inhibitor called naphthylphthalamic acid (NPA) and outline its contribution to our understanding of the molecular mechanisms of polar auxin transport, before proceeding to speculate on how its use is likely still to be informative., (© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

In plants as well as other organisms, protein localization alone is insufficient to provide a mechanistic link between stimulus and process regulation. This is because protein-protein interactions are central to the regulation of biological processes. However, they remain very difficult to detect in situ, with the choice of tools for the detection of protein-protein interaction in situ still in need of expansion. Here, we provide a protocol for the detection and accurate localization of protein interactions based on the combination of a whole-mount proximity ligation assay and iRoCS, a coordinate system able to standardize subtle differences between the architecture of individual Arabidopsis roots.

Systems biology orientates signaling pathways in their biological context. This aim invariably requires models that ignore extraneous factors and focus on the most crucial pathways of any given process. The developing embryo encapsulates many important processes in plant development; understanding their interaction will be key to designing crops able to maximize yield in an ever-more challenging world. Here, we briefly summarize the role of auxin during embryo development. We highlight recent advances in our understanding of auxin signaling and discuss implications for a systems understanding of development., (Copyright © 2016. Published by Elsevier Ltd.)

Lateral roots are initiated postembryonically in response to environmental cues, enabling plants to explore efficiently their underground environment. However, the mechanisms by which the environment determines the position of lateral root formation are unknown. In this study, we demonstrate that in Arabidopsis thaliana lateral root initiation can be induced mechanically by either gravitropic curvature or by the transient bending of a root by hand. The plant hormone auxin accumulates at the site of lateral root induction before a primordium starts to form. Here we describe a subcellular relocalization of PIN1, an auxin transport protein, in a single protoxylem cell in response to gravitropic curvature. This relocalization precedes auxin-dependent gene transcription at the site of a new primordium. Auxin-dependent nuclear signaling is necessary for lateral root formation; arf7/19 double knock-out mutants normally form no lateral roots but do so upon bending when the root tip is removed. Signaling through arf7/19 can therefore be bypassed by root bending. These data support a model in which a root-tip-derived signal acts on downstream signaling molecules that specify lateral root identity.