一种参与真空转移的谷氨S转移酶,由玉米基因Bronze-2编码
K A Marrs1, M R Alfenito, A M Lloyd
1Department of Biological Sciences, Stanford University, California 94305-5020, USA.
Nature
|June 1, 1995
概括
玉米中的铜-2基因编码了一种谷氨S转移酶 (GST) 酶. 这种酶与谷氨结合了安托西亚宁,促进了它们的运输到植物真空中.
科学领域:
- 植物生物化学 植物生物化学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 氨酸S转移酶 (GSTs) 通过形成氨酸合物来排毒异生菌.
- 植物真空层通过特定的将各种分子封存起来,包括除草剂 - 谷氨酸结合物.
- 玉米的青铜-2 (Bz2) 基因对于安托素生物合成和色素沉积至关重要.
研究的目的:
- 为了确定玉米青铜-2 (Bz2) 基因产品的生物化学功能.
- 为了研究Bz2在植物真空体内安托素封存中的作用.
- 探索各种植物分子的真空传输的潜在常见机制.
主要方法:
- 在玉米,Arabidopsis thaliana和Escherichia coli中表达了Bz2基因,以评估GST活性.
- 在表达Bz2.2的玉米原生质中,与谷氨结合的安托西亚宁与谷氨结合.
- 利用谷氨抑制剂瓦纳达特来研究安托素真空积累.
主要成果:
- Bz2编码了一个功能性的谷氨S转移酶酶.
- 来自Bz2表达的玉米原生质的安托西亚宁被发现与谷氨结合.
- 瓦纳达特治疗抑制了反氨酸的真空积累,这表明谷氨酸的作用.
结论:
- Bz2基因产物是一种参与氨酸S转移酶,参与氨酸代谢.
- 抗氨酸的化对于它们在玉米中的真空封存至关重要.
- 植物可能采用一种常见的GST介导机制,将各种分子隔离到真空中.
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