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Science Advances Jun 2024Understanding CRISPR-Cas9's capacity to produce native overexpression (OX) alleles would accelerate agronomic gains achievable by gene editing. To generate OX alleles...
Understanding CRISPR-Cas9's capacity to produce native overexpression (OX) alleles would accelerate agronomic gains achievable by gene editing. To generate OX alleles with increased RNA and protein abundance, we leveraged multiplexed CRISPR-Cas9 mutagenesis of noncoding sequences upstream of the rice gene. We isolated 120 gene-edited alleles with varying non-photochemical quenching (NPQ) capacity in vivo-from knockout to overexpression-using a high-throughput screening pipeline. Overexpression increased OsPsbS1 protein abundance two- to threefold, matching fold changes obtained by transgenesis. Increased PsbS protein abundance enhanced NPQ capacity and water-use efficiency. Across our resolved genetic variation, we identify the role of 5'UTR indels and inversions in driving knockout/knockdown and overexpression phenotypes, respectively. Complex structural variants, such as the 252-kb duplication/inversion generated here, evidence the potential of CRISPR-Cas9 to facilitate significant genomic changes with negligible off-target transcriptomic perturbations. Our results may inform future gene-editing strategies for hypermorphic alleles and have advanced the pursuit of gene-edited, non-transgenic rice plants with accelerated relaxation of photoprotection.
Topics: Oryza; CRISPR-Cas Systems; Gene Editing; Mutagenesis; Alleles; Plant Proteins; Plants, Genetically Modified; Transgenes; Gene Expression Regulation, Plant
PubMed: 38848363
DOI: 10.1126/sciadv.adm7452 -
Physiology and Molecular Biology of... May 2024Reducing protochlorophyllide (Pchlide) to chlorophyllide (Chlide) is a major regulatory step in the chlorophyll biosynthesis pathway. This reaction is catalyzed by... (Review)
Review
Reducing protochlorophyllide (Pchlide) to chlorophyllide (Chlide) is a major regulatory step in the chlorophyll biosynthesis pathway. This reaction is catalyzed by light-dependent protochlorophyllide oxidoreductase (LPOR) in oxygenic phototrophs, particularly angiosperms. LPOR-NADPH and Pchlide form a ternary complex to be efficiently photo-transformed to synthesize Chlide and, subsequently, chlorophyll during the transition from skotomorphogenesis to photomorphogenesis. Besides lipids, carotenoids and poly-cis xanthophylls influence the formation of the photoactive LPOR complexes and the PLBs. The crystal structure of LPOR reveals evolutionarily conserved cysteine residues implicated in the Pchlide binding and catalysis around the active site. Different isoforms of LPOR viz PORA, PORB, and PORC expressed at different stages of chloroplast development play a photoprotective role by quickly transforming the photosensitive Pchlide to Chlide. Non-photo-transformed Pchlide acts as a photosensitizer to generate singlet oxygen that causes oxidative stress and cell death. Therefore, different isoforms of LPOR have evolved and differentially expressed during plant development to protect plants from photodamage and thus play a pivotal role during photomorphogenesis. This review brings out the salient features of LPOR structure, structure-function relationships, and ultra-fast photo transformation of Pchlide to Chlide by oligomeric and polymeric forms of LPOR.
PubMed: 38846463
DOI: 10.1007/s12298-024-01454-5 -
The polyphenolic compound punicalagin protects skin fibroblasts from UVA radiation oxidative damage.Current Research in Pharmacology and... 2024Polyphenols are a class of natural compounds that act as antioxidants, neutralising harmful free radicals that would damage cells and increase the risk of diseases such...
Polyphenols are a class of natural compounds that act as antioxidants, neutralising harmful free radicals that would damage cells and increase the risk of diseases such as cancer, diabetes and heart disease. They also reduce inflammation, which is thought to be at the root of many chronic diseases. We are investigating the photoprotective effects of punicalagin, a type of polyphenolic compound mainly found in pomegranates, against UVA-induced damage in human skin fibroblasts. Punicalagin increases cell viability and reduces the high levels of ROS generated by photooxidative stress through its ability to modulate the Nrf2 transcriptional pathway. Interestingly, activation of the Nrf2 pathway results in an increase in reduced glutathione, NADH, and subsequently protects mitochondrial respiratory capacity. Integrating molecular and imaging approaches, our results demonstrate a potential cytoprotective effect of punicalagin against UVA-induced skin damage through an anti-apoptotic mechanism.
PubMed: 38846010
DOI: 10.1016/j.crphar.2024.100186 -
Photodermatology, Photoimmunology &... Jul 2024Photoprotection is the first measure in the prevention and treatment of the deleterious effects that sunlight can cause on the skin. It is well known that prolonged... (Review)
Review
BACKGROUND
Photoprotection is the first measure in the prevention and treatment of the deleterious effects that sunlight can cause on the skin. It is well known that prolonged exposure to solar radiation leads to acute and chronic complications, such as erythema, accelerated skin aging, proinflammatory and procarcinogenic effects, and eye damage, among others.
METHODS
A better understanding of the molecules that can protect against ultraviolet radiation and their effects will lead to improvements in skin health.
RESULTS
Most of these effects of the sunlight are modulated by oxidative stress and proinflammatory mechanisms, therefore, the supplementation of substances that can regulate and neutralize reactive oxygen species would be beneficial for skin protection. Current evidence indicates that systemic photoprotection should be used as an adjunctive measure to topical photoprotection.
CONCLUSION
Oral photoprotectors are a promising option in improving protection against damage induced by UVR, as they contain active ingredients that increase the antioxidant effects of the body, complementing other photoprotection measures. We present a review of oral photoprotectors and their effects.
Topics: Humans; Administration, Oral; Antioxidants; Oxidative Stress; Reactive Oxygen Species; Skin; Sunlight; Ultraviolet Rays; Protective Agents
PubMed: 38845468
DOI: 10.1111/phpp.12985 -
BMC Ophthalmology Jun 2024The purpose of this study was to investigate the photoprotection effect of peroxiredoxin 1 (PRDX1) protein in ultraviolet B (UVB) irradiation-induced damage of retinal...
BACKGROUND
The purpose of this study was to investigate the photoprotection effect of peroxiredoxin 1 (PRDX1) protein in ultraviolet B (UVB) irradiation-induced damage of retinal pigment epithelium (RPE) and its possible molecular mechanism.
METHODS
ARPE-19 cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the PRDX1 expression. The corresponding kits were employed to measure the levels or activities of lactate dehydrogenase (LDH), 8-hydroxy-2-deoxyguanosine (8-OHdG), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD). Western blotting was applied to examine PRDX1 expression and mitogen-activated protein kinase (MAPK) signaling pathway-related proteins.
RESULTS
After exposure to 20 mJ/cm intensity of UVB irradiation for 24 h, ARPE-19 cells viability was decreased, the leakage degree of LDH and 8-OHdG were increased, and cell apoptosis was elevated. The expression of PRDX1 was significantly down-regulated in UVB-induced ARPE-19 cells. The low expression of PRDX1 was involved in high irradiation intensity. Overexpression of PRDX1 increased cell activity, decreased cell apoptosis, and LDH as well as 8-OHdG leakage in UVB-induced ARPE-19 cells. In addition to alleviating UVB-induced cell damage, PRDX1 overexpression also inhibited UVB-induced oxidative stress (down-regulation of ROS and MDA levels, up-regulation of GSH-Px and SOD activities) and the activation of MAPK signaling pathway in ARPE-19 cells.
CONCLUSION
PRDX1 exerts a photoprotection effect on RPE by attenuating UVB-induced cell damage and inhibiting oxidative stress, which can be attributed to the inhibition of MAPK signaling pathway activation.
Topics: Humans; Oxidative Stress; Retinal Pigment Epithelium; Peroxiredoxins; Ultraviolet Rays; Cell Survival; Apoptosis; Reactive Oxygen Species; MAP Kinase Signaling System; Cell Line; Blotting, Western; Cells, Cultured; 8-Hydroxy-2'-Deoxyguanosine; Signal Transduction
PubMed: 38844903
DOI: 10.1186/s12886-024-03489-4 -
Frontiers in Plant Science 2024The spines of Chinese red chestnut are red and the depth of their color gradually increases with maturity. To identify the anthocyanin types and synthesis pathways in...
The spines of Chinese red chestnut are red and the depth of their color gradually increases with maturity. To identify the anthocyanin types and synthesis pathways in red chestnut and to identify the key genes regulating the anthocyanin biosynthesis pathway, we obtained and analyzed the transcriptome and anthocyanin metabolism of red chestnut and its control variety with green spines at 3 different periods. GO and KEGG analyses revealed that photosynthesis was more highly enriched in green spines compared with red spines, while processes related to defense and metabolism regulation were more highly enriched in red spines. The analysis showed that the change in spine color promoted photoprotection in red chestnut, especially at the early growth stage, which resulted in the accumulation of differentially expressed genes involved in the defense metabolic pathway. The metabolome results revealed 6 anthocyanins in red spines. Moreover, red spines exhibited high levels of cyanidin, peonidin and pelargonidin and low levels of delphinidin, petunidin and malvidin. Compared with those in the control group, the levels of cyanidin, peonidin, pelargonidin and malvidin in red spines were significantly increased, indicating that the cyanidin and pelargonidin pathways were enriched in the synthesis of anthocyanins in red spines, whereas the delphinidin pathways were inhibited and mostly transformed into malvidin. During the process of flower pigment synthesis, the expression of the , , , , , and genes clearly increased, that of decreased obviously, and that of , and both increased and decreased. Notably, the findings revealed that the synthesized anthocyanin can be converted into anthocyanidin or epicatechin. In red spines, the upregulation of gene expression increases the corresponding anthocyanidin content, and the upregulation of the gene also promotes the conversion of anthocyanin to epicatechin. The transcription factors involved in color formation included 4 .
PubMed: 38835869
DOI: 10.3389/fpls.2024.1377899 -
Scientific Reports Jun 2024External eye appearance in avian taxa has been proposed to be driven by social and ecological functions. Recent research in primates suggests, instead, that,...
External eye appearance in avian taxa has been proposed to be driven by social and ecological functions. Recent research in primates suggests, instead, that, photoprotective functions are important drivers of external eye appearance. Using similar methods, we examined the variation in external eye appearance of 132 parrot species (Psittaciformes) in relation to their ecology and sociality. Breeding systems, flock size and sexual dimorphism, as well as species' latitude and maximum living altitude, and estimated UV-B incidence in species' ranges were used to explore the contribution of social and ecological factors in driving external eye appearance. We measured the hue and brightness of visible parts of the eye and the difference in measurements of brightness between adjacent parts of the eye. We found no link between social variables and our measurements. We did, however, find a negative association between the brightness of the inner part of the iris and latitude and altitude. Darker inner irises were more prevalent farther away from the equator and for those species living at higher altitudes. We found no link between UV-B and brightness measurements of the iris, or tissue surrounding the eye. We speculate that these results are consistent with an adaptation for visual functions. While preliminary, these results suggest that external eye appearance in parrots is influenced by ecological, but not social factors.
Topics: Animals; Altitude; Parrots; Eye; Female; Male; Ultraviolet Rays
PubMed: 38834673
DOI: 10.1038/s41598-024-63599-3 -
Journal of Drugs in Dermatology : JDD Jun 2024The debate surrounding the benefits versus harms of blue light have become a topic of interest recently due to increased exposure. Blue light therapy has been utilized... (Review)
Review
The debate surrounding the benefits versus harms of blue light have become a topic of interest recently due to increased exposure. Blue light therapy has been utilized with some success in a variety of dermatologic conditions. However, potential harms have also been documented. Currently, there is no evidence to suggest a necessity for blue light photoprotection, but there are products available with proven efficacy for those desiring protection. J Drugs Dermatol. 2024;23(6):472-476. doi:10.36849/JDD.7665.
Topics: Humans; Light; Skin; Skin Diseases; Phototherapy; Blue Light
PubMed: 38834210
DOI: 10.36849/JDD.7665 -
Photochemistry and Photobiology Jun 2024The field of sun protection is quickly changing and the research article by Douki et al., published in the current issue of Photochemistry and Photobiology, reported...
An important step towards the comprehensive sun protection: Blue-light exposure inhibits DNA repair in reconstituted human skin and a broadband sunscreen avoids this inhibition.
The field of sun protection is quickly changing and the research article by Douki et al., published in the current issue of Photochemistry and Photobiology, reported key experimental data that will certainly help the development of better sun care products. Mutagenic photoproducts (CPDs, cyclobutane pyrimidine dimers and 6-4PPs, pyrimidine-6-4-pyrimidone photoproducts) were formed in the reconstructed human epidermis (RHE) by UVB (312 nm) irradiation, and their concentrations were detected by HPLC-MS/MS as a function of time after the UVB treatment. RHE had been previously exposed or not (control) to blue light (427 nm). Both CPDs and 6-4PPs were shown to last longer in blue-light irradiated RHE, proving the inhibition of the DNA repair by blue light exposure. This is a highly relevant information because sunscreens allow people to enjoy longer periods under the sun and consequently, to endure very high doses of blue light. The work also reported results obtained with RHEs previously treated with a sunscreen formulation containing a broadband filter that offers blue-light protection. Interestingly, authors observed that the DNA repair was not significantly inhibited in RHE previously treated with the sunscreen offering broadband protection. Readers will find a scientifically sound proof of the importance of blue-light protection in sun care products.
PubMed: 38828502
DOI: 10.1111/php.13979