By continuing to use the website or clicking Accept you consent to our cookies and personal data policy and confirm that you are at least 18 year old. For details please see Privacy Policy and Terms
When the DNA sequence for cryptochrome 1 was obtained, it was found that there was significant homology to another class of light-absorbing protein, the DNA photolyases involved in DNA repair and the process of photoreactivation.
Photolyases are DNA repair enzymes that repair damage caused by exposure to ultraviolet light. These enzymes require visible light both for their own activation and for the actual DNA repair. The DNA repair mechanism involving photolyases is called photoreactivation.
Enzymes are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products.
UVR8 has been found to mediate UV-B-induced photomorphogenesis including modulation of biosynthetic pathways, photosynthetic performance, morphogenesis, and responses to pathogens principally in mature light-grown plants.
Given that studies of DNA repair have now provided ample evidence that there are signal transduction pathways activated by DNA lesions, it is not unreasonable to consider DNA itself as a possible photoreceptor.
In just a few seconds, ultraviolet light from the sun can damage DNA by creating hundreds of unwanted links within DNA's double helix. These modifications make the genetic material bulky and unreadable by DNA replication tools, leading to permanent mutations that can cause cancer and other diseases if left unrepaired.
Photolyases belong to the cryptochrome/photolyase protein family (CPF) which perform different functions such as DNA repair, circadian photoreceptor, and transcriptional regulation. Photolyase is a flavoprotein that repairs UV-induced DNA damages of cyclobutane pyrimidine dimer (CPD) and pyrimidine-pyrimidone (6-4) photoproducts using blue-light as an energy source. This enzyme has two chromophores: flavin adenine dinucleotide (FAD) as a cofactor and a photo antenna such as methyltetrahydrofolate (MTHF). The FAD is essential for catalysis of the DNA repair. The second chromophore absorbs photons from the blue light spectrum and transfers energy to FAD to increase the repair efficiency of the enzyme.
UV-B resistance 8 (UVR8) also known as ultraviolet-B receptor UVR8 is a UV-B – sensing protein found in plants and possibly other sources. It is responsible for sensing ultraviolet light in the range 280-315 nm and initiating the plant stress response. 90+% activated at 285nm
If you are interested in the plant's circadian clock, then check out Far-Red photons:
"The R:FR ratio of direct sunlight is about 1[.]5 during most of the day, but it approaches 0[.]6 or so during twilight when the atmosphere preferentially scatters blue light and the sky turns yellow and red. This only lasts for half an hour or less, but it is important because plants use these changes to synchronize their internal circadian clocks both with the24 hour day and the seasons. This involves a burst of gene expression activity that is controlled by phytochrome.”
“Far-Red Lighting and the Phytochromes”, Ian Ashdown, Maximum Yield, maximumyield․com/far-red-lighting-and-the-phytochromes/2/17443
@Ultraviolet, Sometimes I forgot to plan out the best photoperiod schedule and suddenly find myself dramatically shifting the timer once flowering begins. I wonder if hitting them with sunrise/sunset R:FR would alleviate any circadian confusion.
@Natrona, this was my 2 year old dragon willow bonsai, I placed it outside a few weeks back on a sunny day, forgot and it got smoked in a snow storm, thought I'd lost it. Plonked in a copper rod and she came back to life, frankentree.
@Metatronix, Well that's optimistic :)! Every little helps. I found with such a big pot it would allow for unrestricted growth of rootzone, but the water was sitting deep in medium and with the pot taking up so much space it was very hard to keep the medium warm & with very little air getting to where the roots needed it. Prime breeding ground for some bacteria & fungi.
Always been fond of the idea of automating a grow tent for the entire grow, start to finish, the challenge with auto watering was over-watering, this could also dry the medium enough within a timeframe to prevent the conditions for the bacteria n fungi in the first place.
Originally had some ideas for regular-size pots with airstones but then I got stoned and bought a 100-gallon fabric and here we are.
@Ultraviolet, I 💚 the idea ...it really could increase the yields IMO. It would revolutionize the flowerpot industry kind like the Autopot but for soil.
2 strains
2 strains Login
