敏感光化调节视网膜IMPDH1活动和光组件
S John Calise1, Audrey G O'Neill1, Anika L Burrell1
1Department of Biochemistry, University of Washington, Seattle, WA, USA.
The Journal of cell biology
|February 7, 2024
概括
在视网膜中因诺辛单酸脱酶 (IMPDH) 的酸化调节了瓜诺辛三酸 (GTP) 的合成. S477D突变改变了酶组合和活性,在黑暗中降低了GTP的产生.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 视网膜生理学视网膜生理学
背景情况:
- 氨酸单酸脱酶 (IMPDH) 对于氨酸三酸 (GTP) 的合成至关重要,形成增强核酸生产的细丝.
- 脊椎动物的视网膜有两个IMPDDH1拼接变体 (IMPDH1 ((546) 和IMPDH1 ((595)).
- 牛视网膜中的Serine 477 (S477) 酸化依赖于暗色,但其功能影响尚不清楚.
研究的目的:
- 调查S477酸化对IMPDH1活性和丝组件的结构和功能影响.
- 了解S477酸化在视网膜GTP合成中的调节作用.
主要方法:
- 对于两种IMPDH1变种,产生相仿S477D突变物.
- 电子显微镜 (Cryo-EM) 用于确定结构变化.
- 细胞测试以评估主导负效应和丝组合.
主要成果:
- S477D突变使两种IMPDH1变异对GTP反抑制重新敏感.
- S477D 特别破坏了 IMPDH1 的高活性组装接口,但允许 IMPDH1 的光纤形成.
- 在细胞中,S477D表现出主导负效应,抑制了内源性IMPDH光纤组合.
结论:
- S477酸化调节IMPDH结构和光线组合,在黑暗中降低GTP合成的调节.
- 这种酸化作为一种调节机制,在细胞需求较低时减少核酸周转.
更多相关视频
08:00Spatiotemporal Control of Protein Activity through Optogenetic Allosteric Regulation
Published on: October 4, 2024
574
09:32Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development
Published on: June 15, 2017
8.8K
相关概念视频
Disassembly of Intermediate Filaments
2.1K
Intermediate filaments (IFs) do not undergo spontaneous disassembly. Enzymes, kinases, and phosphatases add and remove phosphates from specific sites to regulate their disassembly. The IF concentration in the cytoplasm also regulates the disassembly. If the concentration crosses a threshold, it activates the protein kinases in the vicinity, allowing the phosphorylation of IFs.
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
2.1K
Mechanism of Filopodia Formation
2.3K
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
2.3K
Photoreceptors and Visual Pathways
6.0K
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category,...
6.0K
Phosphoinositides and PIPs
8.5K
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
8.5K
Generation of Straight or Branched Actin Filaments
2.9K
The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
2.9K
