クロロプラストと核の通信は,Mg-protoporphyrinIXの蓄積によって引き起こされます
Asa Strand1, Tadao Asami, Jose Alonso
1Plant Biology Laboratory, The Salk Institute, La Jolla, California 92037, USA.
Nature
|January 4, 2003
まとめ
植物細胞のシグナル伝達分子であるマグネシウム-プロトポルフィリン (Mg-ProtoIX) は,核遺伝子発現を調節する. このテトラピロール中間物質は,植物における光合成に関連するタンパク質生産の調整に不可欠です.
科学分野:
- 植物分子生物学 植物分子生物学
- 光合成の研究研究について
- 細胞シグナリング
背景:
- 植物細胞は,光合成のための核およびプラスティド遺伝子発現を調整する.
- クロロプラストは核遺伝子発現に影響しますが,信号はほとんど不明のままです.
- プラスチドから核への3つの信号伝達経路は知られているが,それらの分子信号は未確認である.
研究 の 目的:
- クロロプラストから核への伝達に関与する分子信号を特定する.
- 核遺伝子発現の調節におけるテトラピロール中間物質の役割を明らかにする.
主な方法:
- クロロプラストと核の間の信号伝達経路を調査した.
- テトラピロール中間物質,特にMg-protoporphyrin (Mg-ProtoIX) に焦点を当てています.
主要な成果:
- 重要なシグナリング分子としてMg-protoporphyrin (Mg-ProtoIX) を特定しました.
- 核遺伝子発現の調節にMg-ProtoIXの蓄積が必要で十分であることを実証した.
- Mg-ProtoIXは,光合成タンパク質をコードする核遺伝子の発現を制御する.
結論:
- Mg-protoporphyrin (Mg-ProtoIX) は,クロロプラストから核への通信を媒介する重要なシグナル伝達分子です.
- この発見は,光合成の座標調節における主要な経路を明確にしています.
- 植物におけるクロロプラストと核の相互作用を理解するための分子基礎を提供する.
関連する概念動画
Anatomy of Chloroplasts
98.4K
Green algae and plants, including green stems and unripe fruit, harbor chloroplasts—the vital organelles where photosynthesis takes place. In plants, the highest density of chloroplasts is found in the mesophyll cells of leaves.
98.4K
Photosystem II
59.8K
The multi-protein complex photosystem II (PS II) harvests photons and transfers their energy through its bound pigments to its reaction center, and ultimately to photosystem I (PSI) through the electron transport chain. The pigments responsible for caputirng the light energy in photosystems include chlorophyll a, chlorophyll b, and carotenoids.
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment...
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment...
59.8K
Photosystem I
52.7K
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
52.7K
The Photochemical Reaction Center
4.4K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
4.4K
The Antenna Complex
6.9K
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...
6.9K
Photosystems
7.0K
Photosystems are multiprotein complexes that form the functional units of photosynthesis in plants, algae, and cyanobacteria. They are found embedded in the membrane of tiny sac-like structures called thylakoids placed inside the chloroplast.
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment...
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment...
7.0K


