| Structural highlights
6gpu is a 1 chain structure with sequence from Arath. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , , , |
| Gene: | PHOT2, CAV1, KIN7, NPL1, At5g58140, K21L19.6 (ARATH) |
| Activity: | Non-specific serine/threonine protein kinase, with EC number 2.7.11.1 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[PHOT2_ARATH] Protein kinase that acts as a blue light photoreceptor in a signal-transduction pathway for photo-induced movements. Mediates calcium spiking of extra- and intracellular origins in response to blue light. Involved in hypocotyl phototropism. Contributes to the chloroplast accumulation in low blue light and mediates their translocation (avoidance response) at high fluence. Regulates stomata opening and photomorphogenesis response of leaf tissue. Not involved in hypocotyl elongation inhibition, anthocyanin accumulation or cotyledon opening.[1] [2] [3] [4] [5]
Publication Abstract from PubMed
miniSOG is the first flavin-binding protein that has been developed with the specific aim of serving as a genetically-encodable light-induced source of singlet oxygen ((1)O2). We have determined its 1.17 A resolution structure, which has allowed us to investigate its mechanism of photosensitization using an integrated approach combining spectroscopic and structural methods. Our results provide a structural framework to explain the ability of miniSOG to produce (1)O2 as a competition between oxygen- and protein quenching of its triplet state. In addition, a third excited-state decay pathway has been identified that is pivotal for the performance of miniSOG as (1)O2 photosensitizer, namely the photo-induced transformation of flavin mononucleotide (FMN) into lumichrome, which increases the accessibility of oxygen to the flavin FMN chromophore and makes protein quenching less favourable. The combination of the two effects explains the increase in the (1)O2 quantum yield by one order of magnitude upon exposure to blue light. Besides, we have identified several surface electron-rich residues that are progressively photo-oxidized, further contributing to facilitate the production of (1)O2. Our results help reconcile the apparent poor level of (1)O2 generation by miniSOG and its excellent performance in correlative light and electron microscopy experiments.
Tailing miniSOG: structural bases of the complex photophysics of a flavin-binding singlet oxygen photosensitizing protein.,Torra J, Lafaye C, Signor L, Aumonier S, Flors C, Shu X, Nonell S, Gotthard G, Royant A Sci Rep. 2019 Feb 20;9(1):2428. doi: 10.1038/s41598-019-38955-3. PMID:30787421[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Sakai T, Kagawa T, Kasahara M, Swartz TE, Christie JM, Briggs WR, Wada M, Okada K. Arabidopsis nph1 and npl1: blue light receptors that mediate both phototropism and chloroplast relocation. Proc Natl Acad Sci U S A. 2001 Jun 5;98(12):6969-74. Epub 2001 May 22. PMID:11371609 doi:http://dx.doi.org/10.1073/pnas.101137598
- ↑ Kagawa T, Sakai T, Suetsugu N, Oikawa K, Ishiguro S, Kato T, Tabata S, Okada K, Wada M. Arabidopsis NPL1: a phototropin homolog controlling the chloroplast high-light avoidance response. Science. 2001 Mar 16;291(5511):2138-41. PMID:11251116 doi:http://dx.doi.org/10.1126/science.291.5511.2138
- ↑ Harada A, Sakai T, Okada K. Phot1 and phot2 mediate blue light-induced transient increases in cytosolic Ca2+ differently in Arabidopsis leaves. Proc Natl Acad Sci U S A. 2003 Jul 8;100(14):8583-8. Epub 2003 Jun 23. PMID:12821778 doi:http://dx.doi.org/10.1073/pnas.1336802100
- ↑ Inada S, Ohgishi M, Mayama T, Okada K, Sakai T. RPT2 is a signal transducer involved in phototropic response and stomatal opening by association with phototropin 1 in Arabidopsis thaliana. Plant Cell. 2004 Apr;16(4):887-96. Epub 2004 Mar 18. PMID:15031408 doi:http://dx.doi.org/10.1105/tpc.019901
- ↑ Ohgishi M, Saji K, Okada K, Sakai T. Functional analysis of each blue light receptor, cry1, cry2, phot1, and phot2, by using combinatorial multiple mutants in Arabidopsis. Proc Natl Acad Sci U S A. 2004 Feb 24;101(8):2223-8. PMID:14982991
- ↑ Torra J, Lafaye C, Signor L, Aumonier S, Flors C, Shu X, Nonell S, Gotthard G, Royant A. Tailing miniSOG: structural bases of the complex photophysics of a flavin-binding singlet oxygen photosensitizing protein. Sci Rep. 2019 Feb 20;9(1):2428. doi: 10.1038/s41598-019-38955-3. PMID:30787421 doi:http://dx.doi.org/10.1038/s41598-019-38955-3
|
