側根誘導系で<em>シロイヌナズナ</em>とトウモロコシ
Summary
The Lateral Root Inducible System (LRIS) allows for synchronous induction of lateral roots and is presented for Arabidopsis thaliana and maize.
Abstract
Lateral root development contributes significantly to the root system, and hence is crucial for plant growth. The study of lateral root initiation is however tedious, because it occurs only in a few cells inside the root and in an unpredictable manner. To circumvent this problem, a Lateral Root Inducible System (LRIS) has been developed. By treating seedlings consecutively with an auxin transport inhibitor and a synthetic auxin, highly controlled lateral root initiation occurs synchronously in the primary root, allowing abundant sampling of a desired developmental stage. The LRIS has first been developed for Arabidopsis thaliana, but can be applied to other plants as well. Accordingly, it has been adapted for use in maize (Zea mays). A detailed overview of the different steps of the LRIS in both plants is given. The combination of this system with comparative transcriptomics made it possible to identify functional homologs of Arabidopsis lateral root initiation genes in other species as illustrated here for the CYCLIN B1;1 (CYCB1;1) cell cycle gene in maize. Finally, the principles that need to be taken into account when an LRIS is developed for other plant species are discussed.
Introduction
それが土壌から、足場と水と栄養素の摂取を保証するため、根系は、植物の成長のために重要です。根系の拡大は主に側根の生産に依存しているため、その開始及び形成が広く研究されています。側根は、創業者セル 1と呼ばれる、鞘細胞の特定のサブセットに開始されます。トウモロコシなどの単子葉植物に、それらは師部の極3に見られるのに対し、このようなシロイヌナズナなどのほとんどの双子葉植物では、これらの細胞は、原生木部の極2に配置されています。創始細胞は、特定の細胞周期遺伝子の発現に続いて増加オーキシン応答4、でマークされている（例えば、 サイクリンB1; 1 / CYCB1; 1）、その後、彼らは非対称背斜部門5の第1ラウンドを受けます。協調背斜と周縁部門の一連の後、側根の原基は、最終的にAと出てくるように形成されていますutonomous側根。これらのイベントが豊富でも同期でもないので、側根開始の位置とタイミングは、しかし、予測可能ではありません。これは、このプロセスを研究するためのトランスクリプトミクス、分子的アプローチの使用を妨げます。
これに対処するには、側根誘導系（LRISは）7,6を開発してきた。このシステムでは、苗を最初に結果的に側根の開始を阻止する、オーキシン輸送と蓄積を阻害するN -1-ナフチルフタラミン酸（NPA）で処理されています8。その後、合成オーキシン1-ナフタレン酢酸（NAA）を含む培地に苗を転送することによって、全体の鞘層が、それによって大量の細胞分裂6を開始する側根を誘導上昇オーキシンレベルに応答します。このように、このシステムは、後半の特定の段階について濃縮根サンプルの容易な収集を可能にする、高速同期と豊富側根のイニシエーションにつながりますRALルート開発。その後、これらのサンプルは、側根形成の間のゲノムワイドな発現プロファイルを決定するために用いることができます。 LRISは、側根のシロイヌナズナの開始とトウモロコシ9-13について、すでにかなりの知識が得られましたが、より多くのゲノムが配列決定されており、経済的な重要に知識を伝達する関心の高まりがあるとして、他の植物種にこのシステムを適用する必要性がより明らかになり、種。
ここでは、 シロイヌナズナやトウモロコシLRISsの詳細なプロトコルが与えられています。次に、システムの使用例は、トウモロコシLRISから得られたトランスクリプトミクスデータが異なる植物種間側根開始時に保存された機能を持つ機能的ホモログを同定するために使用することができる方法を示すことによって、提供されます。最後に、他の植物種のためLRISを最適化するためのガイドラインが提案されています。
Protocol
Representative Results
Discussion
シロイヌナズナ LRISプロトコルでは、それが唯一の完全NPAを含む成長培地と接触して成長した実生を転送することが重要です。これは、側根の開始は全体の根の長さの上にブロックされることを保証します。転送中の小植物を傷つけないようにするために、湾曲した鉗子のアームは、苗の子葉の下に引っ掛けることができます。転送時には、苗の根はNAAを含む寒天培地と十分に接触し?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
The authors thank Davy Opdenacker for technical assistance and photography. We greatly thank Dr. Annick Bleys for helpful suggestions to improve the manuscript. This work was financed by the Interuniversity Attraction Poles Programme IUAP P7/29 ‘MARS’ from the Belgian Federal Science Policy Office, by the FWO grant G027313N and by the Agency for Innovation by Science and Technology, IWT (IR).
Materials
| ARABIDOPSIS LRIS | |||
| Seeds | |||
| Arabidopsis seeds | Col-0 ecotype | ||
| Gas sterilization of seeds | |||
| micro-centrifuge tubes 1.5 ml | SIGMA-ALDRICH | 0030 125.215 | Eppendorf microtubes 3810X, PCR clean |
| micro-centrifuge tubes 2 ml | SIGMA-ALDRICH | 0030 120.094 | Eppendorf Safe-Lock microcentrifuge tubes |
| hydrochloric acid | Merck KGaA | 1,003,171,000 | 37% (fuming) for analysis EMSURE ACS,ISO,Reag. Ph Eu |
| glass desiccator | SIGMA-ALDRICH | Pyrex | |
| glass beaker | |||
| plastic micro-centrifuge tubes box or holder | |||
| Bleach sterilization of seeds | |||
| ethanol | Chem-Lab nv | CL00.0505.1000 | Ethanol, abs. 100% a.r. dilute to 70% |
| sodium hypochlorite (NaOCl) | Carl Roth | 9062.3 | 12% |
| Tween 20 | SIGMA-ALDRICH | P1379 | |
| sterile water | |||
| Growth medium | |||
| Murashige and Skoog salt mixture | DUCHEFA Biochemie B.V. | M0221-0050 | |
| myo-inositol | SIGMA-ALDRICH | I5125-100G | |
| 2-(N-morpholino)ethanesulfonic acid (MES) | DUCHEFA Biochemie B.V. | M1503.0100 | |
| sucrose | VWR, Internation LLC | 27483.294 | D(+)-Sucrose Ph. Eur. |
| KOH | Merck KGaA | 1050211000 | pellets for analysis (max. 0.002% Na) EMSURE ACS,ISO,Reag. Ph Eur |
| Plant Tissue Culture Agar | LabM Limited | MC029 | |
| Lateral root induction chemicals | |||
| N-1-naphthylphthalamic acid (NPA) | DUCHEFA Biochemie B.V. | No. N0926.0250 | 10 µM (Arabidopsis) |
| 1-naphthalene acetic acid (NAA) | DUCHEFA Biochemie B.V. | No. N0903.0050 | 10 µM (Arabidopsis) |
| dimethylsulfoxide (DMSO) | SIGMA-ALDRICH | 494429-1L | |
| Making a mesh for transfer | |||
| nylon mesh | Prosep byba | Synthetic nylon mesh 20 µm | |
| Sowing and seedling handling | |||
| square petri dish plates | GOSSELIN | BP124-05 | 12 x 12 cm |
| 50 ml DURAN tubes | SIGMA-ALDRICH | CLS430304 | Corning 50 mL centrifuge tubes |
| drigalski | Carl Roth | K732.1 | |
| pipette | |||
| cut pipette tips | Daslab | 162001X | Universal 200, cut off 5 mm of tip before autoclaving |
| breathable tape | 3M Deutschland GmbH | cat. no. 1530-1 | |
| tweezers | Fiers nv/sa | K342.1; K344.1 | Dumont tweezers type a nr 5; Dumont tweezers type e nr 7 |
| Growth conditions | |||
| growth room | 21 °C, continuous light | ||
| Materials | Company | Catalog | Comments |
| MAIZE LRIS | |||
| Seeds | |||
| Maize kernels | B-73 | ||
| Bleach sterilization of kernels | |||
| glass beaker | |||
| magnetic stirrer | Fiers nv/sa | C267.1 | |
| sodium hypochlorite (NaOCl) | Carl Roth | 9062.3 | 12% |
| sterile water | |||
| Lateral root induction chemicals | |||
| N-1-naphthylphthalamic acid (NPA) | DUCHEFA Biochemie B.V. | No. N0926.0250 | 50 µM (maize primary root), 25 µM (maize adventitious root) |
| 1-naphthalene acetic acid (NAA) | DUCHEFA Biochemie B.V. | No. N0903.0050 | 50 µM (maize) |
| dimethylsulfoxide (DMSO) | SIGMA-ALDRICH | 494429-1L | |
| Sowing and seedling handling | |||
| paper hand towels | Kimberly-Clark Professional* | 6681 | SCOTT Hand Towels – Roll / White; sheet size (24 x 46 cm) |
| seed germination paper | Anchor Paper Company | 10 X 15 38# seed germination paper | |
| tweezers | Fiers nv/sa | K342.1; K344.1 | Dumont tweezers type a nr 5; Dumont tweezers type e nr 7 |
| 250 ml (centrifuge) tubes | SCHOTT DURAN | 2160136 | approx. 5.6 cm diameter and 14.7 cm height |
| 700 ml tubes | DURAN GROUP | 213994609 | cylinders, round foot tube, D 60 x 250 |
| rack | for maize tubes, home made | ||
| sterile water | |||
| Growth conditions | |||
| growth cabinet | 27 °C, continuous light, 70% relative humidity |
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