AppA是一种蓝光光感受体,可以抗抑制 Rhodobacter sphaeroides 中的光合作用基因表达
1Department of Biology, Indiana University, Bloomington, IN 47405, USA.
Cell
|September 17, 2002
概括
在Rhodobacter sphaeroides中,PpsR抑制器控制着光系统基因表达. 抗抑制剂AppA通过氧化还原和蓝光调节PpsRDNA结合,影响光系统合成.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 光合作用细菌调节光系统合成,以响应氧气和光等环境线索.
- PpsR抑制剂在控制光系统基因表达方面发挥着关键作用.
研究的目的:
- 阐明PpsR抑制剂的氧化还原依赖DNA结合机制.
- 研究抗抑制剂AppA在不同光照条件下调节PpsR活动中的作用.
主要方法:
- 电泳运动转移试验 (EMSAs) 用于研究PpsRDNA结合.
- 用光谱分析来描述AppA的光循环和与PpsR的相互作用.
- 局部定向突变发生,以了解PpsR.中的二硫化键形成.
主要成果:
- PpsR通过分子内二硫化物键以氧化还原依赖的方式与DNA结合.
- AppA通过打破二硫化物键并形成稳定的复合物来对抗PpsR.
- 蓝光激发AppA可以防止AppA-PpsR复合体的形成,释放PpsR抑制.
结论:
- AppA作为一种转录因子,控制光系统基因表达.
- AppA集成氧化还原和蓝光信号来调节PpsRDNA结合.
- 这种机制为光合作用细菌的光系统基因调节提供了全面的理解.
更多相关视频
09:32Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development
Published on: June 15, 2017
08:09Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors
Published on: June 2, 2022
相关概念视频
Photoreceptors and Plant Responses to Light
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.
Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
The Photochemical Reaction Center
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...
Channel Rhodopsins
Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Repressible Operon: trp Operon
The trp operon in Escherichia coli exemplifies a repressible operon. It regulates the synthesis of tryptophan through repressor-mediated transcriptional control and attenuation. This dual regulatory mechanism ensures tryptophan biosynthesis occurs only when needed, conserving cellular resources.Structure of the trp OperonThe trp operon consists of five structural genes (trpE, trpD, trpC, trpB, and trpA) that encode enzymes for tryptophan biosynthesis. These genes are transcribed as a single...
Anoxygenic Phototrophic Bacteria
Anoxygenic phototrophic bacteria are a diverse group of microorganisms that perform photosynthesis without producing oxygen. They primarily include purple sulfur bacteria, purple nonsulfur bacteria, green sulfur bacteria, and green nonsulfur bacteria. These bacteria are classified into the Gammaproteobacteria, Alphaproteobacteria, Betaproteobacteria, Chlorobi, and Chloroflexi lineages, each with distinct physiological and ecological adaptations.Purple sulfur bacteria belong to the...
