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Science Advances Jun 2024Certain cyanobacteria alter their photosynthetic light absorption between green and red, a phenomenon called complementary chromatic acclimation. The acclimation is...
Certain cyanobacteria alter their photosynthetic light absorption between green and red, a phenomenon called complementary chromatic acclimation. The acclimation is regulated by a cyanobacteriochrome-class photosensor that reversibly photoconverts between green-absorbing (Pg) and red-absorbing (Pr) states. Here, we elucidated the structural basis of the green/red photocycle. In the Pg state, the bilin chromophore adopted the extended C15-, structure within a hydrophobic pocket. Upon photoconversion to the Pr state, the bilin is isomerized to the cyclic C15-, structure, forming a water channel in the pocket. The solvation/desolvation of the bilin causes changes in the protonation state and the stability of π-conjugation at the B ring, leading to a large absorption shift. These results advance our understanding of the enormous spectral diversity of the phytochrome superfamily.
Topics: Light; Cyanobacteria; Acclimatization; Photosynthesis; Phytochrome; Models, Molecular; Bile Pigments; Bacterial Proteins; Red Light
PubMed: 38865454
DOI: 10.1126/sciadv.adn8386 -
Plant Cell Reports Jun 202463 L. bicolor WRKY genes were identified and their informatics was analyzed. The results suggested that the LbWRKY genes involved in the development and salt secretion...
63 L. bicolor WRKY genes were identified and their informatics was analyzed. The results suggested that the LbWRKY genes involved in the development and salt secretion of salt glands in L. bicolor. Salt stress, as a universal abiotic stress, severely inhibits the growth and development of plants. WRKY transcription factors play a vital role in plant growth and development, as well as in response to various stresses. Nevertheless, little is known of systematic genome-wide analysis of the WRKY genes in Limonium bicolor, a model recretohalophyte. In this study, 63 L. bicolor WRKY genes were identified (LbWRKY1-63), which were unevenly distributed across seven chromosomes and one scaffold. Based on the structural and phylogenetic characteristics, 63 LbWRKYs are divided into three main groups. Cis-elements in the LbWRKY promoters were related to growth and development, phytohormone responses, and stress responses. Colinearity analysis showed strong colinearity between LbWRKYs and GmWRKYs from soybean (Glycine max). Therefore, LbWRKY genes maybe have similar functions to GmWRKY genes. Expression analysis showed that 28 LbWRKY genes are highly expressed in roots, 9 in stems, 26 in leaves, and 12 in flowers and most LbWRKY genes responded to NaCl, ABA, and PEG6000. Silencing LbWRKY10 reduced salt gland density and salt secretion ability of leaves, and the salt tolerance of the species. Consistent with this, genes associated with salt gland development were markedly down-regulated in the LbWRKY10-silenced lines. Our findings suggested that the LbWRKY genes involved in the development and salt secretion of salt glands in L. bicolor. Our research provides new insights into the functions of the WRKY family in halophytes.
Topics: Plumbaginaceae; Gene Expression Regulation, Plant; Salt-Tolerant Plants; Plant Proteins; Phylogeny; Transcription Factors; Salt Tolerance; Multigene Family; Salt Stress; Stress, Physiological; Plants, Genetically Modified; Promoter Regions, Genetic; Genes, Plant
PubMed: 38865016
DOI: 10.1007/s00299-024-03258-z -
BMC Plant Biology Jun 2024BRVIS RADIX (BRX) family is a small gene family with the highly conserved plant-specific BRX domains, which plays important roles in plant development and response to...
BACKGROUND
BRVIS RADIX (BRX) family is a small gene family with the highly conserved plant-specific BRX domains, which plays important roles in plant development and response to abiotic stress. Although BRX protein has been studied in other plants, the biological function of cotton BRX-like (BRXL) gene family is still elusive.
RESULT
In this study, a total of 36 BRXL genes were identified in four cotton species. Whole genome or segmental duplications played the main role in the expansion of GhBRXL gene family during evolutionary process in cotton. These BRXL genes were clustered into 2 groups, α and β, in which structural and functional conservation within same groups but divergence among different groups were found. Promoter analysis indicated that cis-elements were associated with the phytohormone regulatory networks and the response to abiotic stress. Transcriptomic analysis indicated that GhBRXL2A/2D and GhBRXL5A/5D were up/down-regulated in response to the different stress. Silencing of GhBRXL5A gene via virus-induced gene silencing (VIGS) improved salt tolerance in cotton plants. Furthermore, yeast two hybrid analysis suggested homotypic and heterotypic interactions between GhBRXL1A and GhBRXL5D.
CONCLUSIONS
Overall, these results provide useful and valuable information for understanding the evolution of cotton GhBRXL genes and their functions in salt stress.
Topics: Gossypium; Multigene Family; Plant Proteins; Salt Stress; Gene Expression Regulation, Plant; Salt Tolerance; Phylogeny; Genes, Plant; Gene Expression Profiling
PubMed: 38862893
DOI: 10.1186/s12870-024-05220-3 -
World Journal of Microbiology &... Jun 2024Anaerobic digestion (AD) emerges as a pivotal technique in climate change mitigation, transforming organic materials into biogas, a renewable energy form. This process...
Anaerobic digestion (AD) emerges as a pivotal technique in climate change mitigation, transforming organic materials into biogas, a renewable energy form. This process significantly impacts energy production and waste management, influencing greenhouse gas emissions. Traditional research has largely focused on anaerobic bacteria and methanogens for methane production. However, the potential of anaerobic lignocellulolytic fungi for degrading lignocellulosic biomass remains less explored. In this study, buffalo rumen inocula were enriched and acclimatized to improve lignocellulolytic hydrolysis activity. Two consortia were established: the anaerobic fungi consortium (AFC), selectively enriched for fungi, and the anaerobic lignocellulolytic microbial consortium (ALMC). The consortia were utilized to create five distinct microbial cocktails-AF0, AF20, AF50, AF80, and AF100. These cocktails were formulated based on varying of AFC and ALMC by weights (w/w). Methane production from each cocktail of lignocellulosic biomasses (cassava pulp and oil palm residues) was evaluated. The highest methane yields of CP, EFB, and MFB were obtained at 337, 215, and 54 mL/g VS, respectively. Cocktails containing a mix of anaerobic fungi, hydrolytic bacteria (Sphingobacterium sp.), syntrophic bacteria (Sphaerochaeta sp.), and hydrogenotrophic methanogens produced 2.1-2.6 times higher methane in cassava pulp and 1.1-1.2 times in oil palm empty fruit bunch compared to AF0. All cocktails effectively produced methane from oil palm empty fruit bunch due to its lipid content. However, methane production ceased after 3 days when oil palm mesocarp fiber was used, due to long-chain fatty acid accumulation. Anaerobic fungi consortia showed effective lignocellulosic and starchy biomass degradation without inhibition due to organic acid accumulation. These findings underscore the potential of tailored microbial cocktails for enhancing methane production from diverse lignocellulosic substrates.
Topics: Methane; Anaerobiosis; Lignin; Fungi; Microbial Consortia; Animals; Biomass; Rumen; Biofuels; Hydrolysis; Fermentation; Bacteria; Industrial Waste; Agriculture
PubMed: 38862848
DOI: 10.1007/s11274-024-04050-7 -
Antonie Van Leeuwenhoek Jun 2024Strain MP-1014, an obligate halophilic actinobacterium, was isolated from the mangrove soil of Thandavarayancholanganpettai, Tamil Nadu, India. A polyphasic approach was...
Isoptericola haloaureus sp. nov., a dimorphic actinobacterium isolated from mangrove sediments of southeast India, implicating biosaline agricultural significance through nitrogen fixation and salt tolerance genes.
Strain MP-1014, an obligate halophilic actinobacterium, was isolated from the mangrove soil of Thandavarayancholanganpettai, Tamil Nadu, India. A polyphasic approach was utilized to explore its phylogenetic position completely. The isolate was Gram-positive, filamentous, non-motile, and coccoid in older cultures. Ideal growth conditions were seen at 30 °C and pH 7.0, with 5% NaCl (W/V), and the DNA G + C content was 73.3%. The phylogenic analysis of this strain based upon 16S rRNA gene sequence revealed 97-99.8% similarity to the recognized species of the genus Isoptericola. Strain MP-1014 exhibits the highest similarity to I. sediminis JC619 (99.7%), I. chiayiensis KCTC19740 (98.9%), and subsequently to I. halotolerans KCTC19646 (98.6%), when compared with other members within the Isoptericola genus (< 98%). ANI scores of strain MP-1014 are 86.4%, 84.2%, and 81.5% and dDDH values are 59.7%, 53.6%, and 34.8% with I. sediminis JC619, I. chiayiensis KCTC19740 and I. halotolerans KCTC19646 respectively. The major polar lipids of the strain MP-1014 were phosphatidylinositol, phosphatidylglycerol, diphosphotidylglycerol, two unknown phospholipids, and glycolipids. The predominant respiratory menaquinones were MK (H) and MK (H). The major fatty acids were anteiso-C, anteiso-C, iso-C, C and C. Also, initial genome analysis of the organism suggests it as a biostimulant for enhancing agriculture in saline environments. Based on phenotypic and genetic distinctiveness, the strain MP-1014 represents the novel species of the genus Isoptericola assigned Isoptericola haloaureus sp. nov., is addressed by the strain MP-1014 , given its phenotypic, phylogenetic, and hereditary uniqueness. The type strain is MP-1014 [(NCBI = OP672482.1 = GCA_036689775.1) ATCC = BAA 2646; DSMZ = 29325; MTCC = 13246].
Topics: India; Phylogeny; RNA, Ribosomal, 16S; Salt Tolerance; DNA, Bacterial; Base Composition; Nitrogen Fixation; Wetlands; Fatty Acids; Geologic Sediments; Bacterial Typing Techniques; Soil Microbiology; Phospholipids; Sequence Analysis, DNA; Sodium Chloride; Actinobacteria
PubMed: 38861000
DOI: 10.1007/s10482-024-01985-7 -
Wilderness & Environmental Medicine Jun 2024Griffith Pugh, MD (1909-1994), was a pioneer in altitude physiology. During World War II, he developed training protocols in Lebanon to improve soldier performance at...
Griffith Pugh, MD (1909-1994), was a pioneer in altitude physiology. During World War II, he developed training protocols in Lebanon to improve soldier performance at altitude and in the cold. In 1951 he was chosen to join the British Everest team as a scientist. In preparation, he developed strategies for success on a training expedition on Cho Oyu in 1952. Results from Cho Oyu led to the use of supplemental oxygen at higher flow rates during ascent than used previously (4 L/min vs 2 L/min) and continued use (at a reduced rate of 2 L/min) during descent, enabling increased performance and improved mental acuity. Oxygen was also used during sleep, leading to improved sleep and warmth. Adequate hydration (∼3 L/day) was also stressed, and a more appealing diet led to improved nutrition and condition of the climbers. Improved hygiene practices and acclimatization protocols were also developed. These strategies contributed to the first successful summiting of Mount Everest in 1953. Pugh was then appointed as the lead scientist for a ground-breaking eight-and-a-half-month research expedition where the team was the first to overwinter at high altitude (5800 m) in the Himalayas. This current work summarizes Pugh's scientific contributions as they relate to success on Mount Everest and in inspiring future altitude research by generations of successful researchers.
PubMed: 38860547
DOI: 10.1177/10806032241259499 -
Physiologia Plantarum 2024The effects of transient increases in UVB radiation on plants are not well known; whether cumulative damage dominates or, alternately, an increase in photoprotection and...
The effects of transient increases in UVB radiation on plants are not well known; whether cumulative damage dominates or, alternately, an increase in photoprotection and recovery periods ameliorates any negative effects. We investigated photosynthetic capacity and metabolite accumulation of grapevines (Vitis vinifera Cabernet Sauvignon) in response to UVB fluctuations under four treatments: fluctuating UVB (FUV) and steady UVB radiation (SUV) at similar total biologically effective UVB dose (2.12 and 2.23 kJ m day), and their two respective no UVB controls. We found a greater decrease in stomatal conductance under SUV than FUV. There was no decrease in maximum yield of photosystem II (F/F) or its operational efficiency (ɸ) under the two UVB treatments, and F/F was higher under SUV than FUV. Photosynthetic capacity was enhanced under FUV in the light-limited region of rapid light-response curves but enhanced by SUV in the light-saturated region. Flavonol content was similarly increased by both UVB treatments. We conclude that, while both FUV and SUV effectively stimulate acclimation to UVB radiation at realistic doses, FUV confers weaker acclimation than SUV. This implies that recovery periods between transient increases in UVB radiation reduce UVB acclimation, compared to an equivalent dose of UVB provided continuously. Thus, caution is needed in interpreting the findings of experiments using steady UVB radiation treatments to infer effects in natural environments, as the stimulatory effect of steady UVB is greater than that of the equivalent fluctuating UVB.
Topics: Photosynthesis; Ultraviolet Rays; Acclimatization; Vitis; Photosystem II Protein Complex; Chlorophyll; Plant Stomata; Flavonols
PubMed: 38859677
DOI: 10.1111/ppl.14383 -
Parasites & Vectors Jun 2024Salinity, exacerbated by rising sea levels, is a critical environmental cue affecting freshwater ecosystems. Predicting ecosystem structure in response to such changes...
BACKGROUND
Salinity, exacerbated by rising sea levels, is a critical environmental cue affecting freshwater ecosystems. Predicting ecosystem structure in response to such changes and their implications for the geographical distribution of arthropod disease vectors requires further insights into the plasticity and adaptability of lower trophic level species in freshwater systems. Our study investigated whether populations of the mosquito Culex pipiens, typically considered sensitive to salt, have adapted due to gradual exposure.
METHODS
Mesocosm experiments were conducted to evaluate responses in life history traits to increasing levels of salinity in three populations along a gradient perpendicular to the North Sea coast. Salt concentrations up to the brackish-marine transition zone (8 g/l chloride) were used, upon which no survival was expected. To determine how this process affects oviposition, a colonization experiment was performed by exposing the coastal population to the same concentrations.
RESULTS
While concentrations up to the currently described median lethal dose (LD) (4 g/l) were surprisingly favored during egg laying, even the treatment with the highest salt concentration was incidentally colonized. Differences in development rates among populations were observed, but the influence of salinity was evident only at 4 g/l and higher, resulting in only a 1-day delay. Mortality rates were lower than expected, reaching only 20% for coastal and inland populations and 41% for the intermediate population at the highest salinity. Sex ratios remained unaffected across the tested range.
CONCLUSIONS
The high tolerance to salinity for all key life history parameters across populations suggests that Cx. pipiens is unlikely to shift its distribution in the foreseeable future, with potential implications for the disease risk of associated pathogens.
Topics: Animals; Culex; Female; Oviposition; Salinity; Male; Ecosystem; Salt Tolerance; Fresh Water; Life History Traits; Mosquito Vectors; Lethal Dose 50; Sodium Chloride
PubMed: 38858771
DOI: 10.1186/s13071-024-06268-8 -
Scientific Reports Jun 2024Climate change is intensifying extreme weather events, including marine heatwaves, which are prolonged periods of anomalously high sea surface temperature that pose a...
Climate change is intensifying extreme weather events, including marine heatwaves, which are prolonged periods of anomalously high sea surface temperature that pose a novel threat to aquatic animals. Tropical animals may be especially vulnerable to marine heatwaves because they are adapted to a narrow temperature range. If these animals cannot acclimate to marine heatwaves, the extreme heat could impair their behavior and fitness. Here, we investigated how marine heatwave conditions affected the performance and thermal tolerance of a tropical predatory fish, arceye hawkfish (Paracirrhites arcatus), across two seasons in Moorea, French Polynesia. We found that the fish's daily activities, including recovery from burst swimming and digestion, were more energetically costly in fish exposed to marine heatwave conditions across both seasons, while their aerobic capacity remained the same. Given their constrained energy budget, these rising costs associated with warming may impact how hawkfish prioritize activities. Additionally, hawkfish that were exposed to hotter temperatures exhibited cardiac plasticity by increasing their maximum heart rate but were still operating within a few degrees of their thermal limits. With more frequent and intense heatwaves, hawkfish, and other tropical fishes must rapidly acclimate, or they may suffer physiological consequences that alter their role in the ecosystem.
Topics: Animals; Coral Reefs; Climate Change; Fishes; Perciformes; Acclimatization; Polynesia; Seasons; Hot Temperature; Heart Rate; Extreme Heat
PubMed: 38858427
DOI: 10.1038/s41598-024-63273-8 -
TAG. Theoretical and Applied Genetics.... Jun 2024Our findings highlight a valuable breeding resource, demonstrating the potential to concurrently enhance grain shape, thermotolerance, and alkaline tolerance by...
Our findings highlight a valuable breeding resource, demonstrating the potential to concurrently enhance grain shape, thermotolerance, and alkaline tolerance by manipulating Gγ protein in rice. Temperate Geng/Japonica (GJ) rice yields have improved significantly, bolstering global food security. However, GJ rice breeding faces challenges, including enhancing grain quality, ensuring stable yields at warmer temperatures, and utilizing alkaline land. In this study, we employed CRISPR/Cas9 gene-editing technology to knock out the GS3 locus in seven elite GJ varieties with superior yield performance. Yield component measurements revealed that GS3 knockout mutants consistently enhanced grain length and reduced plant height in diverse genetic backgrounds. The impact of GS3 on the grain number per panicle and setting rate depended on the genetic background. GS3 knockout did not affect milling quality and minimally altered protein and amylose content but notably influenced chalkiness-related traits. GS3 knockout indiscriminately improved heat and alkali stress tolerance in the GJ varieties studied. Transcriptome analysis indicated differential gene expression between the GS3 mutants and their wild-type counterparts, enriched in biological processes related to photosynthesis, photosystem II stabilization, and pathways associated with photosynthesis and cutin, suberine, and wax biosynthesis. Our findings highlight GS3 as a breeding resource for concurrently improving grain shape, thermotolerance, and alkaline tolerance through Gγ protein manipulation in rice.
Topics: Oryza; Thermotolerance; Edible Grain; Plant Proteins; Plant Breeding; Gene Expression Regulation, Plant; Phenotype; Gene Editing; Alkalies; CRISPR-Cas Systems; Plants, Genetically Modified
PubMed: 38856926
DOI: 10.1007/s00122-024-04669-y