Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 57
Filter
Add more filters











Publication year range
1.
Langmuir ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39226404

ABSTRACT

In many commercial applications, polymer-dye interactions are frequently encountered from food to wastewater treatment, and while shear rheology has been well characterized, the extensional properties are not well known. The extensional viscosity ηE and relaxation time λE are the extensional rheological parameters that provide valuable insights into how aqueous polymers respond during deformation, and this study investigated the effect of dyes on the extensional rheology of three different aqueous polymer solutions (e.g., anionic, cationic, and neutral) paired with two different dye salts (e.g., anionic and cationic) using drop pinch-off experiments. We have found that the influence of dyes on the pinch-off dynamics is complex but generally leads to a decrease in, for example, the apparent extensional relaxation time. We have utilized the dripping-onto-substrate method to probe the uniaxial deformation of widely used polymers such as xanthan gum (XG), poly(diallyldimethylammonium chloride) (PDADMAC), and poly(ethylene oxide) (PEO) as the anionic, cationic, and neutral polymers, respectively, paired with either fluorescein (Fl) or methylene blue (MB) as the anionic and cationic dyes, respectively. Polymer-dye pairs with opposite charges (e.g., XG-MB and PDADMAC-Fl) displayed a pronounced decrease in pinch-off times, but even PEO, which is a neutral polymer, resulted in decreased pinch-off times, which was restored by the addition of NaCl. The pinch-off times for the Boger fluid (mixture of poly(ethylene glycol) and PEO), however, were surprisingly uninfluenced by dyes. These results showed that not only did the small addition of dyes strongly decrease the polymer relaxation times, but the relative importance of the dye salts on the polymer pinch-off dynamics was also different from that of pure salts such as NaCl.

2.
J Colloid Interface Sci ; 677(Pt A): 557-568, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39111091

ABSTRACT

HYPOTHESIS: Lysopalmitoylphosphatidylcholine (LysoPC) is a soluble single-chain surfactant product of the innate immune system degradation of double-chain phospholipids. LysoPC adsorption to the air-water interface in lung alveoli can be modeled using alveolar-sized bubbles of constant surface area in a capillary pressure microtensiometer to show that adsorption is diffusion limited both below and above the critical micelle concentration (CMC). Above the CMC, a local equilibrium model is proposed in which depletion of the local monomer concentration drives dissociation of micelles in a region near the bubble surface. EXPERIMENTAL: A capillary pressure microtensiometer in which a feedback loop maintains a constant bubble radius and surface area is used to measure dynamic surface tension during LysoPC adsorption. Direct numerical solution of the spherical diffusion equations, a new three parameter virial equation of state for interface thermodynamics, and a local equilibrium model of micellization above the CMC are used to accurately model the dynamic surface tension experiments both below and above the LysoPC CMC. FINDINGS: LysoPC adsorption is shown to be diffusion-limited over concentrations ranging from below to well above the CMC, and to be well described by a local equilibrium model at concentrations above the CMC. Modelling the dynamic surface tension provides a reliable estimate of the micelle diffusivity near the CMC that is difficult to obtain by other methods in systems with low CMCs.

3.
BMC Complement Med Ther ; 24(1): 315, 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39179999

ABSTRACT

BACKGROUND: Metabolic syndrome (MetS) is a precursor to the development of many diseases (atherosclerosis, diabetes, etc.). It is marked by disruptions in glucose and lipid metabolism, along with hypertension. Numerous types of risk factors contribute to the development of the MetS, inflammation and insulin resistance are present throughout the metabolic abnormalities. Chrysanthemum indicum L. is a traditional Chinese plant used for both tea and medicine, known for its high content of total flavonoids, which are important secondary metabolites. Our research led to the extraction of a Buddleoside-Rich Chrysanthemum indicum L. extract (BUDE) which has demonstrated anti-inflammatory properties. Nonetheless, the specific role and mechanism of BUDE in preventing MetS remain unclear. METHODS: The study initially evaluated the role of BUDE in preventing MetS. Subsequently, it investigated the anti-inflammatory properties of BUDE in the liver and pancreas in response to unhealthy diets. It then examined the level of insulin resistance and pancreatic ß-cell function induced by inflammation. Additionally, an lipopolysaccharide (LPS)-induced macrophage inflammation model was used to further investigate the ameliorative effects of BUDE in inflammation. RESULTS: BUDE has hypotensive, hypoglycemic and hypolipidemic effects. It can also resolve the imbalance between macrophage subpopulations, impede the triggering of the NF-κB signaling pathway, reduce the secretion of inflammatory mediators, ameliorate insulin resistance, and safeguard organs such as the liver and pancreas from inflammatory damage. These effects collectively contribute to preventing the development of MetS. DISCUSSION: BUDE has the ability to modulate macrophage-mediated inflammation, leading to improved insulin resistance. Additionally, it delivers antihypertensive, hypoglycemic, and hypolipidemic effects, offering a potential for preventing MetS.


Subject(s)
Chrysanthemum , Inflammation , Macrophages , Metabolic Syndrome , Plant Extracts , Chrysanthemum/chemistry , Metabolic Syndrome/drug therapy , Animals , Inflammation/drug therapy , Mice , Male , Plant Extracts/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Insulin Resistance , Anti-Inflammatory Agents/pharmacology , Mice, Inbred C57BL , Rats , Disease Models, Animal
4.
Int J Mol Sci ; 25(16)2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39201361

ABSTRACT

Plant recognition of pathogen-associated molecular patterns (PAMPs) is pivotal in triggering immune responses, highlighting their potential as inducers of plant immunity. However, the number of PAMPs identified and applied in such contexts remains limited. In this study, we characterize a novel PAMP, designated Ss4368, which is derived from Scleromitrula shiraiana. Ss4368 is specifically distributed among a few fungal genera, including Botrytis, Monilinia, and Botryotinia. The transient expression of Ss4368 elicits cell death in a range of plant species. The signaling peptides, three conserved motifs, and cysteine residues (C46, C88, C112, C130, and C148) within Ss4368 are crucial for inducing robust cell death. Additionally, these signaling peptides are essential for the protein's localization to the apoplast. The cell death induced by Ss4368 and its homologous protein, Bc4368, is independent of the SUPPRESSOR OF BIR1-1 (SOBIR1), BRI1-ASSOCIATED KINASE-1 (BAK1), and salicylic acid (SA) pathways. Furthermore, the immune responses triggered by Ss4368 and Bc4368 significantly enhance the resistance of Nicotiana benthamiana to Phytophthora capsici. Therefore, we propose that Ss4368, as a novel PAMP, holds the potential for developing strategies to enhance plant resistance against P. capsici.


Subject(s)
Cell Death , Disease Resistance , Nicotiana , Pathogen-Associated Molecular Pattern Molecules , Phytophthora , Plant Diseases , Plant Immunity , Phytophthora/pathogenicity , Disease Resistance/genetics , Plant Diseases/microbiology , Plant Diseases/genetics , Pathogen-Associated Molecular Pattern Molecules/metabolism , Nicotiana/microbiology , Nicotiana/genetics , Fungal Proteins/metabolism , Fungal Proteins/genetics , Plant Proteins/metabolism , Plant Proteins/genetics , Gene Expression Regulation, Plant , Plant Cells/metabolism , Plant Cells/microbiology
5.
Mol Biol Evol ; 41(4)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38507653

ABSTRACT

Although gene loss is common in evolution, it remains unclear whether it is an adaptive process. In a survey of seven major mangrove clades that are woody plants in the intertidal zones of daily environmental perturbations, we noticed that they generally evolved reduced gene numbers. We then focused on the largest clade of Rhizophoreae and observed the continual gene set reduction in each of the eight species. A great majority of gene losses are concentrated on environmental interaction processes, presumably to cope with the constant fluctuations in the tidal environments. Genes of the general processes for woody plants are largely retained. In particular, fewer gene losses are found in physiological traits such as viviparous seeds, high salinity, and high tannin content. Given the broad and continual genome reductions, we propose the May-Wigner theory (MWT) of system stability as a possible mechanism. In MWT, the most effective solution for buffering continual perturbations is to reduce the size of the system (or to weaken the total genic interactions). Mangroves are unique as immovable inhabitants of the compound environments in the land-sea interface, where environmental gradients (such as salinity) fluctuate constantly, often drastically. Extending MWT to gene regulatory network (GRN), computer simulations and transcriptome analyses support the stabilizing effects of smaller gene sets in mangroves vis-à-vis inland plants. In summary, we show the adaptive significance of gene losses in mangrove plants, including the specific role of promoting phenotype innovation and a general role in stabilizing GRN in unstable environments as predicted by MWT.


Subject(s)
Gene Regulatory Networks , Genome , Gene Expression Profiling , Plants
6.
Nat Commun ; 15(1): 1635, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38388712

ABSTRACT

Whole-genome duplication (WGD), or polyploidy, events are widespread and significant in the evolutionary history of angiosperms. However, empirical evidence for rediploidization, the major process where polyploids give rise to diploid descendants, is still lacking at the genomic level. Here we present chromosome-scale genomes of the mangrove tree Sonneratia alba and the related inland plant Lagerstroemia speciosa. Their common ancestor has experienced a whole-genome triplication (WGT) approximately 64 million years ago coinciding with a period of dramatic global climate change. Sonneratia, adapting mangrove habitats, experienced extensive chromosome rearrangements post-WGT. We observe the WGT retentions display sequence and expression divergence, suggesting potential neo- and sub-functionalization. Strong selection acting on three-copy retentions indicates adaptive value in response to new environments. To elucidate the role of ploidy changes in genome evolution, we improve a model of the polyploidization-rediploidization process based on genomic evidence, contributing to the understanding of adaptive evolution during climate change.


Subject(s)
Genome , Genomics , Genome/genetics , Plants/genetics , Chromosomes , Genome, Plant/genetics , Polyploidy , Evolution, Molecular , Phylogeny , Gene Duplication
7.
J Integr Plant Biol ; 66(4): 824-843, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38372488

ABSTRACT

Nypa fruticans (Wurmb), a mangrove palm species with origins dating back to the Late Cretaceous period, is a unique species for investigating long-term adaptation strategies to intertidal environments and the early evolution of palms. Here, we present a chromosome-level genome sequence and assembly for N. fruticans. We integrated the genomes of N. fruticans and other palm family members for a comparative genomic analysis, which confirmed that the common ancestor of all palms experienced a whole-genome duplication event around 89 million years ago, shaping the distinctive characteristics observed in this clade. We also inferred a low mutation rate for the N. fruticans genome, which underwent strong purifying selection and evolved slowly, thus contributing to its stability over a long evolutionary period. Moreover, ancient duplicates were preferentially retained, with critical genes having experienced positive selection, enhancing waterlogging tolerance in N. fruticans. Furthermore, we discovered that the pseudogenization of Early Methionine-labelled 1 (EM1) and EM6 in N. fruticans underly its crypto-vivipary characteristics, reflecting its intertidal adaptation. Our study provides valuable genomic insights into the evolutionary history, genome stability, and adaptive evolution of the mangrove palm. Our results also shed light on the long-term adaptation of this species and contribute to our understanding of the evolutionary dynamics in the palm family.


Subject(s)
Arecaceae , Arecaceae/genetics , Genomics
8.
Plant J ; 117(2): 432-448, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37850375

ABSTRACT

Coastal forests, such as mangroves, protect much of the tropical and subtropical coasts. Long-distance dispersal via sea-surfing propagules is essential for coastal plants, but the genomic and molecular basis of sea-surfing plant propagule evolution remains unclear. Heritiera fomes and Heritiera littoralis are two coastal plants with typical buoyant fruits. We de novo sequenced and assembled their high-quality genomes. Our phylogenomic analysis indicates H. littoralis and H. fomes originated (at ~6.08 Mya) just before the start of Quaternary sea-level fluctuations. Whole-genome duplication occurred earlier, permitting gene copy gains in the two species. Many of the expanded gene families are involved in lignin and flavonoid biosynthesis, likely contributing to buoyant fruit emergence. It is repeatedly revealed that one duplicated copy to be under positive selection while the other is not. By examining H. littoralis fruits at three different developmental stages, we found that gene expression levels remain stable from young to intermediate. However, ~1000 genes are up-regulated and ~ 3000 genes are down-regulated as moving to mature. Particularly in fruit epicarps, the upregulation of WRKY12 and E2Fc likely constrains the production of p-Coumaroyl-CoA, the key internal substrate for lignin biosynthesis. Hence, to increase fruit impermeability, methylated lignin biosynthesis is shut down by down-regulating the genes CCoAOMT, F5H, COMT, and CSE, while unmethylated lignins are preferentially produced by upregulating CAD and CCR. Similarly, cutin polymers and cuticular waxes accumulate with high levels before maturation in epicarps. Overall, our genome assemblies and analyses uncovered the genomic evolution and temporal transcriptional regulation of sea-surfing propagule.


Subject(s)
Lignin , Plants , Lignin/metabolism , Plants/metabolism , Fruit/genetics , Fruit/metabolism , Phylogeny , Gene Expression Regulation, Plant/genetics
9.
Plant Biotechnol J ; 22(6): 1491-1503, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38157253

ABSTRACT

Mangrove species are broadly classified as true mangroves and mangrove associates. The latter are amphibious plants that can survive in the intertidal zone and reproduce naturally in terrestrial environments. Their widespread distribution and extensive adaptability make them ideal research materials for exploring adaptive evolution. In this study, we de novo assembled two genomes of mangrove associates (the allotetraploid Barringtonia racemosa (2n = 4x = 52) and diploid Barringtonia asiatica (2n = 2x = 26)) to investigate the role of allopolyploidy in the evolutionary history of mangrove species. We developed a new allotetraploid-dividing tool Allo4D to distinguish between allotetraploid scaffold-scale subgenomes and verified its accuracy and reliability using real and simulated data. According to the two subgenomes of allotetraploid B. racemosa divided using Allo4D, the allopolyploidization event was estimated to have occurred approximately one million years ago (Mya). We found that B. racemosa, B. asiatica, and Diospyros lotus shared a whole genome duplication (WGD) event during the K-Pg (Cretaceous-Paleozoic) period. K-Pg WGD and recent allopolyploidization events contributed to the speciation of B. racemosa and its adaptation to coastal habitats. We found that genes in the glucosinolates (GSLs) pathway, an essential pathway in response to various biotic and abiotic stresses, expanded rapidly in B. racemosa during polyploidization. In summary, this study provides a typical example of the adaptation of allopolyploid plants to extreme environmental conditions. The newly developed tool, Allo4D, can effectively divide allotetraploid subgenomes and explore the evolutionary history of polyploid plants, especially for species whose ancestors are unknown or extinct.


Subject(s)
Genome, Plant , Tetraploidy , Genome, Plant/genetics , Evolution, Molecular , Rhizophoraceae/genetics , Polyploidy , Phylogeny , Biological Evolution
10.
Langmuir ; 39(48): 17551-17559, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37987777

ABSTRACT

To improve the rate of DWC, numerous studies have adjusted the distribution of drops through biphilic surface patterning and wettability gradients to control the nucleation and drop shedding rates on the condensing surface, yet the connection between drop shedding mechanisms and surface wettability patterning remains unclear. Moreover, wettability patterning places geometric bounds on the governing forces (i.e., gravity, capillary, and inertia), which drive the droplet shedding mechanisms. Thus, the subsequent influence of droplet distribution along the DWC regions on the shedding mechanisms may not be known a priori. In this study, the area fraction, ADWC, of the DWC and also the DWC region width, LN, were varied between 10 and 50% and 0.5-1.5 mm, respectively, to probe the dominant droplet shedding mechanisms on a high wettability contrast surface (i.e., the contact angle on the DWC was 159 ± 3.4° and the hysteresis 9 ± 3.6°, whereas the FWC was nearly perfectly wetting). Humid air was introduced inside a custom-built chamber with the upright steady-state condensation imaged by both real-time and high-speed imaging techniques. We found that the droplet shedding mechanisms changed with increasing LN where the sliding drop radii are reduced with LN while the jumping drop radii remained unchanged with LN. The maximum drop size for shedding also decreased by 13%, which we attribute to the secondary droplet inertia, which helps gravity overcome the capillary retention force. Lastly, although many studies have probed DWC enhancements via surface wettability patterning, an optimal combination of ADWC and LN provided in this study significantly aids in the improvement of future DWC-based condensers and water collector applications.

11.
Mol Ecol Resour ; 2023 Sep 09.
Article in English | MEDLINE | ID: mdl-37688468

ABSTRACT

Ecological restoration of mangrove ecosystems that became susceptible to recent habitat perturbations is crucial for tropical coast conservation. The white mangrove Laguncularia racemosa, a pioneer species inhabiting intertidal environments of the Atlantic East Pacific (AEP) region, has been used for reforestation in China for decades. However, the molecular mechanisms underlying its fast growth and high adaptive potential remain unknown. Using PacBio single-molecule real-time sequencing, we completed a high-quality L. racemosa genome assembly covering 1105 Mb with scaffold N50 of 3.46 Mb. Genomic phylogeny shows that L. racemosa invaded intertidal zones during a period of global warming. Multi-level genomic convergence analyses between L. racemosa and three native dominant mangrove clades show that they experienced convergent changes in genes involved in nutrient absorption and high salinity tolerance. This may explain successful L. racemosa adaptation to stressful intertidal environments after introduction. Without recent whole-genome duplications or activated transposable elements, L. racemosa has retained many tandem gene duplications. Some of them are involved in auxin biosynthesis, intense light stress and cold stress response pathways, associated with L. racemosa's ability to grow fast under high light or cold conditions when used for reforestation. In summary, our study identifies shared mechanisms of intertidal environmental adaptation and unique genetic changes underlying fast growth in mangrove-unfavourable conditions and sheds light on the molecular mechanisms of the white mangrove utility in ecological restoration.

12.
Int J Biol Macromol ; 253(Pt 4): 126987, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37729987

ABSTRACT

Polysaccharides are known to confer protection against glycolipid metabolism disorders (GMD) by regulating intestinal flora. In this study, a heterogeneous acidic heteropolysaccharide with high molecular weight mainly composed of fructose was isolated from Atractylodes macrocephala Koidz (AMP). Supplementation with AMP was shown to improve diet-induced GMD in a rat model, including decreasing the levels of serum triglycerides, total cholesterol, and glucose, and improving hepatic lipidosis and islet cells morphologies. AMP-treated rats also exhibited modified intestinal flora with enrichments of intestinal Lactobacillus and Rothia species, which was accompanied by increased tryptophan metabolites such as indole-3-propionic acid, indole, tryptamine, and tryptophol. These metabolites promote the expression of intestinal aryl hydrocarbon receptor (AhR) in nuclear fractions. AhR activation increased the expression levels of IL-22 and GLP-1 proteins and mRNA. IL-22 reduced systemic LPS by upregulating the expression of tight junction proteins, antimicrobial peptides, and mucin to ameliorate intestinal barrier function, and activated the hepatic IL-22R/Stat3/Acox1 signaling pathway to improve lipid metabolism. GLP-1 activated the pancreatic GLP-1R/p-CREB signaling pathway to ameliorate ß-cell injury and improve insulin resistance. Therefore, the intestinal microbial-tryptophan metabolism-AhR pathway was deduced to be a mechanism by which this polysaccharide improves GMD.


Subject(s)
Atractylodes , Gastrointestinal Microbiome , Rats , Animals , Atractylodes/chemistry , Tryptophan/metabolism , Receptors, Aryl Hydrocarbon/metabolism , Indoles , Polysaccharides/chemistry , Lipid Metabolism , Glucagon-Like Peptide 1
13.
Mar Life Sci Technol ; 5(2): 155-168, 2023 May.
Article in English | MEDLINE | ID: mdl-37275537

ABSTRACT

Mangroves are adapted to intertidal zones, which present extreme environmental conditions. WRKYs are among the most prominent transcription factors (TFs) in higher plants and act through various interconnected networks to regulate responses to multiple abiotic stressors. Here, based on omic data, we investigated the landscape and evolutionary patterns of WRKYs in the main mangrove genus Avicennia. We found that both the number and the proportion of TFs and WRKYs in Avicennia species exceeded their inland relatives, indicating a significant expansion of WRKYs in Avicennia. We identified 109 WRKY genes in the representative species Avicennia marina. Comparative genomic analysis showed that two recent whole-genome duplication (WGD) events played a critical role in the expansion of WRKYs, and 88% of Avicennia marina WRKYs (AmWRKYs) have been retained following these WGDs. Applying comparative transcriptomics on roots under experimental salt gradients, we inferred that there is high divergence in the expression of WGD-retained AmWRKYs. Moreover, we found that the expression of 16 AmWRKYs was stable between freshwater and moderately saline water but increased when the trees were exposed to high salinity. In particular, 14 duplicates were retained following the two recent WGD events, indicating potential neo- and sub-functionalization. We also found that WRKYs could interact with other upregulated genes involved in signalling pathways and natural antioxidant biosynthesis to enhance salt tolerance, contributing to the adaptation to intertidal zones. Our omic data of the WRKY family in A. marina broadens the understanding of how a TF family relates to the adaptive evolution of mangroves. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00177-y.

14.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13438-13453, 2023 11.
Article in English | MEDLINE | ID: mdl-37379199

ABSTRACT

The privacy and security of face data on social media are facing unprecedented challenges as it is vulnerable to unauthorized access and identification. A common practice for solving this problem is to modify the original data so that it could be protected from being recognized by malicious face recognition (FR) systems. However, such "adversarial examples" obtained by existing methods usually suffer from low transferability and poor image quality, which severely limits the application of these methods in real-world scenarios. In this paper, we propose a 3D-Aware Adversarial Makeup Generation GAN (3DAM-GAN). which aims to improve the quality and transferability of synthetic makeup for identity information concealing. Specifically, a UV-based generator consisting of a novel Makeup Adjustment Module (MAM) and Makeup Transfer Module (MTM) is designed to render realistic and robust makeup with the aid of symmetric characteristics of human faces. Moreover, a makeup attack mechanism with an ensemble training strategy is proposed to boost the transferability of black-box models. Extensive experiment results on several benchmark datasets demonstrate that 3DAM-GAN could effectively protect faces against various FR models, including both publicly available state-of-the-art models and commercial face verification APIs, such as Face++, Baidu, and Aliyun.


Subject(s)
Facial Recognition , Privacy , Humans , Algorithms , Benchmarking
15.
Int J Mol Sci ; 24(8)2023 Apr 16.
Article in English | MEDLINE | ID: mdl-37108516

ABSTRACT

While most of the species in Goodeniaceae family, excluding the Scaevola genus, are endemic to Australasia, S. taccada and S. hainanensis have expanded their distribution range to the tropical coastlines of the Atlantic and Indian Oceans. S. taccada appears to be highly adapted to coastal sandy lands and cliffs, and it has become invasive in places. S. hainanensis is found mainly in salt marshes near mangrove forests, and is at risk of extinction. These two species provide a good system to investigate adaptive evolution outside the common distribution range of this taxonomic group. Here, we report their chromosomal-scale genome assemblies with the objective of probing their genomic mechanisms related to divergent adaptation after leaving Australasia. The scaffolds were assembled into eight chromosome-scale pseudomolecules, which covered 90.12% and 89.46% of the whole genome assembly for S. taccada and S. hainanensis, respectively. Interestingly, unlike many mangroves, neither species has undergone whole-genome duplication. We show that private genes, specifically copy-number expanded genes are essential for stress response, photosynthesis, and carbon fixation. The gene families that are expanded in S. hainanensis and contracted in S. taccada might have facilitated adaptation to high salinity in S. hainanensis. Moreover, the genes under positive selection in S. hainanensis have contributed to its response to stress and its tolerance of flooding and anoxic environments. In contrast, compared with S. hainanensis, the more drastic copy number expansion of FAR1 genes in S. taccada might have facilitated its adaptation to the stronger light radiation present in sandy coastal lands. In conclusion, our study of the chromosomal-scale genomes of S. taccada and S. hainanensis provides novel insights into their genomic evolution after leaving Australasia.


Subject(s)
Magnoliopsida , Adaptation, Physiological/genetics , Acclimatization , Plants , Chromosomes
16.
Mol Ecol ; 32(6): 1351-1365, 2023 03.
Article in English | MEDLINE | ID: mdl-35771769

ABSTRACT

How plants adapt and diverge in extreme environments is a key question of plant evolution and ecology. Mangrove invasion of intertidal environments is facilitated by adaptive phenotypes such as aerial roots, salt-secreting leaf, and viviparity, and genomic mechanisms including whole genome duplication and transposable element number reduction. However, a number of mangroves lack these typical phenotypes. The question we ask is whether these phenotypically atypical mangroves also have distinct genomic features? The sibling mangrove species Lumnitzera littorea and Lumnitzera racemosa provide a model to study this question. We sequenced and assembled their genomes to chromosome level, together with a closely related species Combretum micranthum. While most mangroves have small genomes, the genomes of both Lumnitzera species are large (1443 and 1317 Mb) and carry a high proportion of repeat sequences (~75%). Moreover, Lumnitzera species have not undergone post-gamma whole-genome duplications. Their genome size increased mainly due to the expansion of repeat sequences in their ancestors. However, Lumnitzera genomes have reduced transposable elements by constraining the proliferation of new LTR-RTs. Meanwhile, the two species have more gene families contracted than expanded, and some gene families with reversed size change may underlie their differentiation in root morphology and local distribution. We identified 86 chromosomal inversions, five of which are measured between 6.5 and 12.8 megabases. A number of genes located in these inversions function in pigment biosynthesis, a process likely involved in flower colour differentiation between the Lumnitzera species. We conclude that the mangroves with atypical phenotypes also have atypical genomic evolution.


Subject(s)
Adaptation, Physiological , DNA Transposable Elements , DNA Transposable Elements/genetics , Adaptation, Physiological/genetics , Plants/genetics , Acclimatization , Genomics
17.
Mol Ecol ; 32(2): 460-475, 2023 01.
Article in English | MEDLINE | ID: mdl-34882881

ABSTRACT

Whole-genome duplication (WGD) is believed to increase the chance of adaptation to a new environment. This conjecture may apply particularly well to new environments that are not only different but also more variable than ancestral habitats. One such prominent environment is the interface between land and sea, which has been invaded by woody plants, collectively referred as mangroves, multiple times. Here, we use two distantly related mangrove species (Avicennia marina and Rhizophora apiculata) to explore the effects of WGD on the adaptive process. We found that a high proportion of duplicated genes retained after WGD have acquired derived differential expression in response to salt gradient treatment. The WGD duplicates differentially expressed in at least one copy usually (>90%) diverge from their paralogues' expression profiles. Furthermore, both species evolved in parallel to have one paralogue expressed at a high level in both fresh water and hypersaline conditions but at a lower level at medium salinity. The pattern contrasts with the conventional view of monotone increase/decrease as salinity increases. Differentially expressed copies have thus probably acquired a new role in salinity tolerance. Our results indicate that the WGD duplicates may have evolved to function collaboratively in coping with different salinity levels, rather than specializing in the intermediate salinity optimal for mangrove plants. In conclusion, WGD and the retained duplicates appear to be an effective solution for adaptation to new and unstable environments.


Subject(s)
Gene Duplication , Salinity , Genome , Adaptation, Physiological/genetics , Plants/genetics
18.
Science ; 378(6621): 747-754, 2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36395230

ABSTRACT

The mixtures of cations and anions used in hybrid halide perovskites for high-performance solar cells often undergo element and phase segregation, which limits device lifetime. We adapted Schelling's model of segregation to study individual cation migration and found that the initial film inhomogeneity accelerates materials degradation. We fabricated perovskite films (FA1-xCsxPbI3; where FA is formamidinium) through the addition of selenophene, which led to homogeneous cation distribution that retarded cation aggregation during materials processing and device operation. The resultant devices achieved enhanced efficiency and retained >91% of their initial efficiency after 3190 hours at the maximum power point under 1 sun illumination. We also observe prolonged operational lifetime in devices with initially homogeneous FACsPb(Br0.13I0.87)3 absorbers.

19.
Appl Opt ; 61(22): 6671-6676, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-36255894

ABSTRACT

Photonics-assisted instantaneous frequency measurement of a microwave signal using a silicon integrated microring resonator (MRR) is proposed and experimentally demonstrated. The frequency of a microwave signal has a unique relationship with the power ratio between the two microwave signals at the outputs of two microwave photonic filters (MPF) with complementary frequency responses. The key device to implement the MPFs is a silicon integrated MMR, which is employed to convert a phase-modulated optical signal to an intensity-modulated optical signal by placing two optical carriers at the complementary slopes of the MRR. For a given frequency measurement range and resolution, an MRR is designed and fabricated, and its use for instantaneous microwave frequency (IMF) measurement is implemented. For the fabricated MRR, an IMF measurement range of 14-25 GHz with a measurement accuracy of ±0.2GHz is achieved.

20.
Phytomedicine ; 106: 154404, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36075182

ABSTRACT

BACKGROUND: Metabolic hypertension (MH) is characterized by elevated blood pressure accompanied by metabolic abnormalities, with the gut-derived lipopolysaccharide/toll like receptor 4 (LPS/TLR4) pathway an important triggering mechanism. The conventional Chinese plant Polygonatum sibiricum Red. is traditionally used as a medicinal and edible food source. Currently, several studies have examined its anti-obesity and anti-diabetic actions, with potential roles for MH treatment; however, specific P. sibiricum Red. roles in MH and associated mechanisms remain unclear. OBJECTIVES: Our purpose was to identify the effects and mechanisms of P. sibiricum Red. superfine powder (PSP) in a MH rat model triggered by high sugar and high fat compounds in an excessive alcohol diet (ACHSFDs). METHODS: A MH rat model was induced by ACHSFDs, and PSP was administered daily at 0.5 and 1.0 g/kg doses, respectively. Firstly, the effects of PSP on MH were assessed using blood pressure, serum lipid, and lipid deposition assays in the liver. Changes in intestinal flora were detected by high-throughput 16S rRNA sequencing, while metabolite short-chain fatty acids (SCFAs) and LPS levels were quantified by gas chromatography (GC) and enzyme-linked immunosorbent assay (ELISA), respectively. Hematoxylin & eosin (H&E) staining and transmission electron microscopy (TEM) were performed to evaluate histopathological changes in the rat colon. d-lactic acid (d-LA) levels and tight junction proteins (TJPs) expression were also measured to assess intestinal barrier function. Also, aortic endothelial microstructures, serum endothelin 1 (ET-1), and nitric oxide (NO) levels were investigated to determine vascular endothelial function. Finally, the TLR4/MyD88 signaling pathway in the aorta and gut was evaluated by western blotting, immunohistochemistry (IHC), and quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Blood pressure and blood lipid metabolism disorders induced by ACHSFDs in MH rats were improved by PSP administration. Intestinal flora analyses revealed decreased SCFAs and LPS levels following PSP administration, which was accompanied by increased Streptococcus species levels and decreased Desulfobacter and Desulfovibrio species levels. PSP increased SCFAs levels, and the expression of SCFAs receptors GPCR41 and GPCR43 in the colon. Meanwhile, the expression of tight junction proteins (TJPs) such as Claudin-1, occludin were upregulated in the ileum and colon, while TLR4 and MyD88 were downregulated, thereby strengthening intestinal barrier integrity and reducing serum LPS levels. Additionally, PSP treatment improved vascular endothelial function by inhibiting the TLR4/MyD88 pathway in vessels, improving vascular endothelial cell shedding, and regulating the NO and ET-1 balance. CONCLUSIONS: We demonstrated the beneficial effects and potential mechanisms of PSP in our MH rat model. Based on gut microbiota structure modulation and intestinal barrier improvements, PSP inhibited LPS-induced vascular TLR4/MyD88 signaling activation to improve vascular endothelial function, which in turn reduced blood pressure. Our study provides valuable insights on PSP therapy for MH.


Subject(s)
Hypertension , Polygonatum , Animals , Claudin-1/metabolism , Endothelin-1/metabolism , Eosine Yellowish-(YS) , Fatty Acids, Volatile , Hematoxylin , Hypertension/drug therapy , Lactic Acid , Lipopolysaccharides/pharmacology , Myeloid Differentiation Factor 88/metabolism , Nitric Oxide/metabolism , Occludin/metabolism , Polygonatum/chemistry , Powders , RNA, Ribosomal, 16S , Rats , Sugars , Toll-Like Receptor 4/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL