UV-B for a 5x5
- Thread starter BigRed469
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rkymtnman
Well-Known Member
i switched from uvb to uva. uvb i couldn't run 12 hours, uva i can. i figure if the sun has it, that's good enough reason to have it
jimihendrix1
Well-Known Member
You have to have UVB that goes down to 285nm to activate the UVR8 Protein Receptor.
Solacure goes down to 280nm. And is the only one I know of that goes under 290nm.
Flower Power is a broadband UV bulb (ie: it covers everything from 280nm to 380nm
UV-B resistance 8 (UVR8) also known as ultraviolet-B receptor UVR8 is an UV-B – sensing protein found in plants and possibly other sources.[2] It is responsible for sensing ultraviolet light in the range 280-315 nm and initiating the plant stress response. It is most sensitive at 285nm, near the lower limit of UVB. UVR8 was first identified as a crucial mediator of a plant's response to UV-B in Arabidopsis thaliana containing a mutation in this protein. This plant was found to have a hypersensitivity to UV-B[3] which damages DNA. UVR8 is thought to be a unique photoreceptor as it doesn't contain a prosthetic chromophore but its light-sensing ability is intrinsic to the molecule.[4] Tryptophan (Trp) residue 285 has been suggested to act the UV-B sensor, while other Trp residues have been also seen to be involved (Trp233 > Trp337 > Trp94) although in-vivo data suggests that Trp285 and Trp233 are most important.[2]
Evolution[edit]
Although the complete genome sequence is only available from a limited number of angiosperms, bioinformatic analysis suggests that there are a large number of UVR8 orthologs. Both number and position of key residues seem to be well conserved among angiosperms but also other plant species (e.g., Chlamydomonas reinhardtii and Volvox carteri). The latter implies that UVR8 potentially appeared before the evolutionary split in vascular land plants which would be rational considering that at that time the amount of UV-B radiation that penetrated the earth surface was higher as the ozone layer was not fully developed, hence UV protection and acclimation would be of crucial importance.[5]
Structure[edit]
UVR8 is a β-propeller protein with 7 blade-shaped β-sheets. It shares sequence homology with mammalian proteins involved in regulating chromatin condensation, for example the human RCC1 gene product. In the dark state, UVR8 forms a homodimer that is localized in the cytosol, but UV-B illumination induces the dissociation of UVR8 dimer to its respective monomers and translocation to the nucleus occurs.[6] The dimer is held together via a complex salt bridge network.[2]
Mechanism[edit]
Upon UV-B irradiation, light is absorbed by one or more Trp residues which are situated adjacent to Arg residues which form salt bridges across the dimer interface. It is thought that this light absorption induces the disruption of the salt-bridges and thus leads to the molecule's monomerization.[2][7] Following monomerization, UVR8 accumulates in the nucleus where it interacts with a protein called constitutively photomorphogenic 1 (COP1). COP1 is known to act as an E3 Ubiquitin ligase that targets key transcription factors for ubiquitination and proteasome-mediated degradation. However, in the case of UVR8, it has been shown to act as a positive regulator of UVR8-mediated UV-B signalling.[8] Upon UV-B illumination, UVR8 interacts via a C-terminal 27 amino acid region with the WD40 domain of COP1 in the nucleus,[9] which triggers the induction of ELONGATED HYPOCOTYL 5 (HY5) — a key transcription factor for several UV-B responsive genes, and overall results in UV-B acclimation.[10]
Solacure goes down to 280nm. And is the only one I know of that goes under 290nm.
Flower Power is a broadband UV bulb (ie: it covers everything from 280nm to 380nm
UV-B resistance 8 (UVR8) also known as ultraviolet-B receptor UVR8 is an UV-B – sensing protein found in plants and possibly other sources.[2] It is responsible for sensing ultraviolet light in the range 280-315 nm and initiating the plant stress response. It is most sensitive at 285nm, near the lower limit of UVB. UVR8 was first identified as a crucial mediator of a plant's response to UV-B in Arabidopsis thaliana containing a mutation in this protein. This plant was found to have a hypersensitivity to UV-B[3] which damages DNA. UVR8 is thought to be a unique photoreceptor as it doesn't contain a prosthetic chromophore but its light-sensing ability is intrinsic to the molecule.[4] Tryptophan (Trp) residue 285 has been suggested to act the UV-B sensor, while other Trp residues have been also seen to be involved (Trp233 > Trp337 > Trp94) although in-vivo data suggests that Trp285 and Trp233 are most important.[2]
Evolution[edit]
Although the complete genome sequence is only available from a limited number of angiosperms, bioinformatic analysis suggests that there are a large number of UVR8 orthologs. Both number and position of key residues seem to be well conserved among angiosperms but also other plant species (e.g., Chlamydomonas reinhardtii and Volvox carteri). The latter implies that UVR8 potentially appeared before the evolutionary split in vascular land plants which would be rational considering that at that time the amount of UV-B radiation that penetrated the earth surface was higher as the ozone layer was not fully developed, hence UV protection and acclimation would be of crucial importance.[5]
Structure[edit]
UVR8 is a β-propeller protein with 7 blade-shaped β-sheets. It shares sequence homology with mammalian proteins involved in regulating chromatin condensation, for example the human RCC1 gene product. In the dark state, UVR8 forms a homodimer that is localized in the cytosol, but UV-B illumination induces the dissociation of UVR8 dimer to its respective monomers and translocation to the nucleus occurs.[6] The dimer is held together via a complex salt bridge network.[2]
Mechanism[edit]
Upon UV-B irradiation, light is absorbed by one or more Trp residues which are situated adjacent to Arg residues which form salt bridges across the dimer interface. It is thought that this light absorption induces the disruption of the salt-bridges and thus leads to the molecule's monomerization.[2][7] Following monomerization, UVR8 accumulates in the nucleus where it interacts with a protein called constitutively photomorphogenic 1 (COP1). COP1 is known to act as an E3 Ubiquitin ligase that targets key transcription factors for ubiquitination and proteasome-mediated degradation. However, in the case of UVR8, it has been shown to act as a positive regulator of UVR8-mediated UV-B signalling.[8] Upon UV-B illumination, UVR8 interacts via a C-terminal 27 amino acid region with the WD40 domain of COP1 in the nucleus,[9] which triggers the induction of ELONGATED HYPOCOTYL 5 (HY5) — a key transcription factor for several UV-B responsive genes, and overall results in UV-B acclimation.[10]
Last edited:
jimihendrix1
Well-Known Member
Beyond Arabidopsis: Differential UV-B Response …
pubmed.ncbi.nlm.nih.gov
This mechanism has been thoroughly characterized in Arabidopsis, where studies have demonstrated that the UVR8 receptor is key in UV-B response. Although Arabidopsis importance as a model plant many mechanisms described in this specie differ in other plants.
Jun 11, 2013 · The UVR8 UV-B photoreceptor exists as a homodimer that instantly monomerises upon UV-B absorption via specific intrinsic tryptophans which act as UV-B chromophores. The UVR8 monomer interacts with COP1, an E3 ubiquitin ligase, initiating a molecular signaling pathway that leads to gene expression changes.
UVR8 Chemical Profile Shaping in Cannabis — AgricUltra ...
www.agricultra.com
UVR8 Chemical Profile Shaping in Cannabis UVB+A light on a dynamic spectrum allows growers to develop lighting schedules that shape terpene profiles and increase other secondary metabolites. This allows them to take common genetics and develop proprietary …
Beyond Arabidopsis: Differential UV-B Response Mediated by UVR8 in Diverse Species - PubMed
Ultraviolet-B radiation (UV-B, 280-315 nm) is an important environmental signal that regulates growth and development in plants. Two dose-dependent UV-B response pathways were described in plants: a specific one, mediated by UVR8 (the specific UV-B receptor) and an unspecific one, activated by...
- Cited by: 32
- Publish Year: 2019
Jun 11, 2013 · The UVR8 UV-B photoreceptor exists as a homodimer that instantly monomerises upon UV-B absorption via specific intrinsic tryptophans which act as UV-B chromophores. The UVR8 monomer interacts with COP1, an E3 ubiquitin ligase, initiating a molecular signaling pathway that leads to gene expression changes.
- UVR8 interacts with de novo DNA methyltransferase and ...
Jan 25, 2021 · Nature Plants - In Arabidopsis, the UV receptor UVR8 is functionally connected to DNA methylase DRM2. Through this interaction, UV light prevents DRM2 association with chromatin, suppressing DNA...
UVR8 interacts with de novo DNA methyltransferase and suppresses DNA methylation in Arabidopsis - Nature Plants
In Arabidopsis, the UV receptor UVR8 is functionally connected to DNA methylase DRM2. Through this interaction, UV light prevents DRM2 association with chromatin, suppressing DNA methylation and the associated transcriptional changes.
www.nature.com
UVR8 Chemical Profile Shaping in Cannabis — AgricUltra ...
UVR8 Chemical Profile Shaping in Cannabis — AgricUltra™ Advancements
The potency of high quality marijuana increases in direct ratio to the amount of UVB light it receives.
www.agricultra.com