A Forward Genetic Approach to Identify Plasmodesmal Trafficking Regulators Based on Trichome Rescue

Plasmodesmata (PD) are channels in the walls of plant cells which enable cell-to-cell information transfer. This includes the selective transport of specific transcription factors that control cell fate during plant development. KNOTTED1 (KN1) homeobox (KNOX) family transcription factors that are essential for the maintenance and function of stem cells in shoot meristems use this trafficking pathway, but its mechanism is largely unknown. Here we describe a forward genetic approach to the identification of regulators of selective KN1 trafficking through PD, using a trichome rescue system that permits simple visual analysis in Arabidopsis leaves. A KN1 trafficking regulator identified in this approach had the capacity to regulate the transport not only of KN1 but also of another mobile regulatory protein, TRANSPARENT TESTA GLABRA1 (TTG1). Our system could be easily adapted to reveal the mechanism underlying the selective transport of additional mobile signals through PD

Trafficking and localization of KNOTTED1 related mRNAs in shoot meristems

Multicellular organisms use transcripts and proteins as signaling molecules for cell-to-cell communication. Maize KNOTTED1 (KN1) was the first homeodomain transcription factor identified in plants, and functions in maintaining shoot stem cells. KN1 acts non-cell autonomously, and both its messenger RNA (mRNA) and protein traffic between cells through intercellular nanochannels called plasmodesmata. KN1 protein and mRNA trafficking are regulated by a chaperonin subunit and a catalytic subunit of the RNA exosome, respectively. These studies suggest that the function of KN1 in stem cell regulation requires the cell-to-cell transport of both its protein and mRNA. However, in situ hybridization experiments published 25 years ago suggested that KN1 mRNA was missing from the epidermal (L1) layer of shoot meristems, suggesting that only the KN1 protein could traffic. Here, we show evidence that KN1 mRNA is present at a low level in L1 cells of maize meristems, supporting an idea that both KN1 protein and mRNA traffic to the L1 layer. We also summarize mRNA expression patterns of KN1 homologs in diverse angiosperm species, and discuss KN1 trafficking mechanisms

Quantitative Imaging Reveals Distinct Contributions of SnRK2 and ABI3 in Plasmodesmatal Permeability in Physcomitrella patens

Cell-to-cell communication is tightly regulated in response to environmental stimuli in plants. We previously used a photoconvertible fluorescent protein Dendra2 as a model reporter to study this process. This experiment revealed that macromolecular trafficking between protonemal cells in Physcomitrella patens is suppressed in response to abscisic acid (ABA). However, it remains unknown which ABA signaling components contribute to this suppression and how. Here, we show that ABA signaling components SUCROSE NON-FERMENTING 1-RELATED PROTEIN KINASE 2 (PpSnRK2) and ABA INSENSITIVE 3 (PpABI3) play roles as an essential and promotive factor, respectively, in regulating ABA-induced suppression of Dendra2 diffusion between cells (ASD). Our quantitative imaging analysis revealed that disruption of PpSnRK2 resulted in defective ASD onset itself, whereas disruption of PpABI3 caused an 81-min delay in the initiation of ASD. Live-cell imaging of callose deposition using aniline blue staining showed that, despite this onset delay, callose deposition on cross walls remained constant in the PpABI3 disruptant, suggesting that PpABI3 facilitates ASD in a callose-independent manner. Given that ABA is an important phytohormone to cope with abiotic stresses, we further explored cellular physiological responses. We found that the acquisition of salt stress tolerance is promoted by PpABI3 in a quantitative manner similar to ASD. Our results suggest that PpABI3-mediated ABA signaling may effectively coordinate cell-to-cell communication during the acquisition of salt stress tolerance. This study will accelerate the quantitative study for ABA signaling mechanism and function in response to various abiotic stresses

An Optimized Whole-Mount Immunofluorescence Method for Shoot Apices.

The localization of a protein provides important information about its biological functions. The visualization of proteins by immunofluorescence has become an essential approach in cell biology. Here, we describe an easy-to-follow immunofluorescence protocol to localize proteins in whole-mount tissues of maize (Zea mays) and Arabidopsis. We present the whole-mount immunofluorescence procedure using maize ear primordia and Arabidopsis inflorescence apices as examples, followed by tips and suggestions for each step. In addition, we provide a supporting protocol to describe the use of an ImageJ plug-in to analyze colocalization. This protocol has been optimized to observe proteins in 2-5 mm maize ear primordia or in developing Arabidopsis inflorescence apices; however, it can be used as a reference to perform whole-mount immunofluorescence in other plant tissues and species. © 2021 Wiley Periodicals LLC. Basic Protocol: Whole-mount immunofluorescence for maize and Arabidopsis shoot apices Support Protocol: Measure colocalization by JACoP plugin in ImageJ

Industrialization and Its Effects on the Region in India

まえがき はじめに 1 第1部 M.P.州における工業化の新展開と地域構造の変容 : ピータンプル工業成長センターの事例を中心に 　マデイヤ・プラデーシュ州における工業開発政策と工業成長センター : ピータンプル工業成長センターの開発を中心として / 岡橋 秀典・友澤 和夫 3 　インド・ピータンプル工業成長センターにおける工業立地の展開と生産システム / 友澤 和夫 29 　ピータンプル工業成長センターにおけるインフラストラクチャー整備 : 水供給を中心に / 南埜 猛 63 　新興工業団地に近接する農村・チラカーンの概要 / 南埜 猛 85 　工業団地開発と近接農村の社会構造 : インド・M.P.州チラカーン村の事例 / 澤 宗則 107 　工業団地開発と近接農村の農業構造 : インド・M.P.州チラカーン村の事例 / 荒木 一視 141 　インド・ピータンプル工業成長センターの開発と住宅供給問題 : ハウジング・コロニーの開発と居住者の特徴 / 由井義通 173 　インド・ピータンプル工業成長センターの開発による都市化と中心機能の集積 / 作野広和 205 　GISを用いた海外地誌データの分析 : インド・センサスデータの分析を例に / 佐藤 崇徳・作野 広和・杉浦 真一郎・岡橋 秀典 235 第2部 デリー首都圏地域における工業化の新展開と地域構造の変容 : ノイダ・グレーターノイダの事例を中心に 　デト首都圏地域(NCR)における工業団地開発 : 総合工業団地としてのノイダおよびグレーターノイダ地区の開発を中心として / 岡橋 秀典 263 　デト首都圏における自動車工業の集積とその地域構造 : ノイダ, グレーター・ノイダを事例として / 友澤 和夫 287 　インドにおける都市化・工業化と農民の対応 : デト大都市圏農村の事例 / 南埜 猛 307 　インドの都市近接農村における社会・経済システムの変化 : ノイダ工業団地近接農村を事例に / 澤 宗則 341 　大都市近接農村における農業の変容 : インドの首都デトに近接するR村の事例 / 荒木 一視 357 　デト首都圏地域(N.C.R.)ノイダの都市開発と住宅供給 : 住宅供給と居住者の特徴 / 由井義通 371 　インド・ノイダ工業団地における商業中心地の成立過程 / 作野 広和 397 　インド農村調査におけるGISの導入 : センサスデータおよび現地調査データのGIS化への試み / 佐藤 崇徳・作野 広和 425研究期間:平成8-10年度 ; 研究種目:国際学術研究・学術調査 ; 課題番号: 0804101