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1.
BMC Plant Biol ; 21(1): 474, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663209

RESUMO

BACKGROUND: Plant annexins are calcium- and lipid-binding proteins that have multiple functions, and a significant amount of research on plant annexins has been reported in recent years. However, the functions of annexins in diverse biological processes in rice are largely unclear. RESULTS: Herein, we report that OsANN4, a calcium-binding rice annexin protein, was induced by abscisic acid (ABA). Under ABA treatment, the plants in which OsANN4 was knocked down by RNA interference showed some visible phenotypic changes compared to the wild type, such as a lower rooting rate and shorter shoot and root lengths. Moreover, the superoxide dismutase (SOD) and catalase (CAT) activities of the RNAi lines were significantly lower and further resulted in higher accumulation of O2.- and H2O2 than those of the wild-type. A Non-invasive Micro-test Technology (NMT) assay showed that ABA-induced net Ca2+ influx was inhibited in OsANN4 knockdown plants. Interestingly, the phenotypic differences caused by ABA were eliminated in the presence of LaCl3 (Ca2+ channel inhibitor). Apart from this, we demonstrated that OsCDPK24 interacted with and phosphorylated OsANN4. When the phosphorylated serine residue of OsANN4 was substituted by alanine, the interaction between OsANN4 and OsCDPK24 was still observed, however, both the conformation of OsANN4 and its binding activity with Ca2+ might be changed. CONCLUSIONS: OsANN4 plays a crucial role in the ABA response, partially by modulating ROS production, mediating Ca2+ influx or interacting with OsCDPK24.

3.
Foods ; 10(6)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199820

RESUMO

Natural polysaccharides and their metabolites' short chain fatty acids (SCFAs) have attracted much attention. Recently, they have shown great potential in attenuating systemic inflammation activities, especially in inflammatory bowel disease (IBD). IBD is a complex pathological process and is related to epithelial damage and microbiota imbalance in the gut. Recent studies have indicated that natural polysaccharides could improve IBD recovery by different mechanisms. They could not only influence the ratio of intestine microbiota, but also regulate the secretion levels of immunity cytokines through multiple pathways, the latter including modulation of the TLR/MAPK/NF-κB signaling pathways and stimulation of G-protein-coupled receptors. Moreover, they could increase intestinal integrity and modulate oxidative stress. In this review, recent research about how natural polysaccharides impact the pathogenesis of IBD are summarized to prove the association between polysaccharides and disease recovery, which might contribute to the secretion of inflammatory cytokines, improve intestine epithelial damage, reduce oxidative stress, sustain the balanced microenvironment of the intestines, and finally lower the risk of IBD.

4.
Dalton Trans ; 49(37): 13052-13059, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32924043

RESUMO

A dual-functional urea-linked conjugated porous polymer (UCPP) assembled by enol-imine with ordered unit arrays that act as potential anchoring sites in the networks was fabricated, and was further applied as a support for Ag nanoparticles by the coordinate interaction between them. The UCPP not only can well confine the Ag particle size and facilitate high dispersion, but also can afford special CO2-philic moieties to enhance the adsorption properties. The resulting Ag@UCPP as a heterogeneous catalyst exhibited excellent activity for the carboxylative cyclization of propargyl alcohols with CO2 under mild conditions, together with good recyclability, which is probably attributed to the synergistic effect of the UCPP on the adsorption and activation of CO2 and the immobilization of Ag nanoparticles. This work affords possible opportunities for the design and synthesis of a heterogeneous catalyst toward CO2 conversion.

5.
EMBO J ; 39(13): e103630, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32449547

RESUMO

Light and temperature are two core environmental factors that coordinately regulate plant growth and survival throughout their entire life cycle. However, the mechanisms integrating light and temperature signaling pathways in plants remain poorly understood. Here, we report that CBF1, an AP2/ERF-family transcription factor essential for plant cold acclimation, promotes hypocotyl growth under ambient temperatures in Arabidopsis. We show that CBF1 increases the protein abundance of PIF4 and PIF5, two phytochrome-interacting bHLH-family transcription factors that play pivotal roles in modulating plant growth and development, by directly binding to their promoters to induce their gene expression, and by inhibiting their interaction with phyB in the light. Moreover, our data demonstrate that CBF1 promotes PIF4/PIF5 protein accumulation and hypocotyl growth at both 22°C and 17°C, but not at 4°C, with a more prominent role at 17°C than at 22°C. Together, our study reveals that CBF1 integrates light and temperature control of hypocotyl growth by promoting PIF4 and PIF5 protein abundance in the light, thus providing insights into the integration mechanisms of light and temperature signaling pathways in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Hipocótilo/crescimento & desenvolvimento , Temperatura , Transativadores/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hipocótilo/genética , Transativadores/genética
6.
Plant Cell ; 32(7): 2196-2215, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32371543

RESUMO

Phytochromes are red (R) and far-red (FR) light photoreceptors in plants, and PHYTOCHROME-INTERACTING FACTORS (PIFs) are a group of basic helix-loop-helix family transcription factors that play central roles in repressing photomorphogenesis. Here, we report that MYB30, an R2R3-MYB family transcription factor, acts as a negative regulator of photomorphogenesis in Arabidopsis (Arabidopsis thaliana). We show that MYB30 preferentially interacts with the Pfr (active) forms of the phytochrome A (phyA) and phytochrome B (phyB) holoproteins and that MYB30 levels are induced by phyA and phyB in the light. It was previously shown that phytochromes induce rapid phosphorylation and degradation of PIFs upon R light exposure. Our current data indicate that MYB30 promotes PIF4 and PIF5 protein reaccumulation under prolonged R light irradiation by directly binding to their promoters to induce their expression and by inhibiting the interaction of PIF4 and PIF5 with the Pfr form of phyB. In addition, our data indicate that MYB30 interacts with PIFs and that they act additively to repress photomorphogenesis. In summary, our study demonstrates that MYB30 negatively regulates Arabidopsis photomorphogenic development by acting to promote PIF4 and PIF5 protein accumulation under prolonged R light irradiation, thus providing new insights into the complicated but delicate control of PIFs in the responses of plants to their dynamic light environment.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica de Plantas , Luz , Fitocromo A/metabolismo , Fitocromo B/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Plântula/fisiologia , Fatores de Transcrição/genética
7.
Mol Plant ; 13(3): 414-430, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32059872

RESUMO

PHYTOCHROME-INTERACTING FACTORS (PIFs) are a group of basic helix-loop-helix transcription factors that can physically interact with photoreceptors, including phytochromes and cryptochromes. It was previously demonstrated that PIFs accumulated in darkness and repressed seedling photomorphogenesis, and that PIFs linked different photosensory and hormonal pathways to control plant growth and development. In this study, we show that PIFs positively regulate the ABA signaling pathway during the seedling stage specifically in darkness. We found that PIFs positively regulate ABI5 transcript and protein levels in darkness in response to exogenous ABA treatment by binding directly to the G-box motifs in the ABI5 promoter. Consistently, PIFs and the G-box motifs in the ABI5 promoter determine ABI5 expression in darkness, and overexpression of ABI5 could rescue the ABA-insensitive phenotypes of pifq mutants in the dark. Moreover, we discovered that PIFs can physically interact with the ABA receptors PYL8 and PYL9, and that this interaction is not regulated by ABA. Further analyses showed that PYL8 and PYL9 promote PIF4 protein accumulation in the dark and enhance PIF4 binding to the ABI5 promoter, but negatively regulate PIF4-mediated ABI5 activation. Taken together, our data demonstrate that PIFs interact with ABA receptors to orchestrate ABA signaling in darkness by controlling ABI5 expression, providing new insights into the pivotal roles of PIFs as signal integrators in regulating plant growth and development.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Escuridão , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos da radiação , RNA Mensageiro/genética , Transdução de Sinais/efeitos da radiação
8.
Nucleic Acids Res ; 48(D1): D971-D976, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31584086

RESUMO

As the largest ethnic group in the world, the Han Chinese population is nonetheless underrepresented in global efforts to catalogue the genomic variability of natural populations. Here, we developed the PGG.Han, a population genome database to serve as the central repository for the genomic data of the Han Chinese Genome Initiative (Phase I). In its current version, the PGG.Han archives whole-genome sequences or high-density genome-wide single-nucleotide variants (SNVs) of 114 783 Han Chinese individuals (a.k.a. the Han100K), representing geographical sub-populations covering 33 of the 34 administrative divisions of China, as well as Singapore. The PGG.Han provides: (i) an interactive interface for visualization of the fine-scale genetic structure of the Han Chinese population; (ii) genome-wide allele frequencies of hierarchical sub-populations; (iii) ancestry inference for individual samples and controlling population stratification based on nested ancestry informative markers (AIMs) panels; (iv) population-structure-aware shared control data for genotype-phenotype association studies (e.g. GWASs) and (v) a Han-Chinese-specific reference panel for genotype imputation. Computational tools are implemented into the PGG.Han, and an online user-friendly interface is provided for data analysis and results visualization. The PGG.Han database is freely accessible via http://www.pgghan.org or https://www.hanchinesegenomes.org.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Bases de Dados Genéticas , Genética Populacional , Genoma Humano , Genômica , China , Grupos Étnicos/genética , Genômica/métodos , Humanos , Software , Design de Software , Navegador
10.
Genome Biol ; 20(1): 215, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640808

RESUMO

Despite the tremendous growth of the DNA sequencing data in the last decade, our understanding of the human genome is still in its infancy. To understand the implications of genetic variants in the light of population genetics and molecular evolution, we developed a database, PGG.SNV ( https://www.pggsnv.org ), which gives much higher weight to previously under-investigated indigenous populations in Asia. PGG.SNV archives 265 million SNVs across 220,147 present-day genomes and 1018 ancient genomes, including 1009 newly sequenced genomes, representing 977 global populations. Moreover, estimation of population genetic diversity and evolutionary parameters is available in PGG.SNV, a unique feature compared with other databases.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Bases de Dados Genéticas , Doença/genética , Genoma Humano , Polimorfismo de Nucleotídeo Único , Evolução Molecular , Frequência do Gene , Variação Genética , Humanos , Povos Indígenas/genética
11.
Front Physiol ; 10: 345, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984026

RESUMO

The exocyst complex plays multiple roles via tethering secretory or recycling vesicles to the plasma membrane. Previous studies have demonstrated that the exocyst contains eight components, which possibly have some redundant but distinct functions. It is therefore interesting to investigate the biological function of each component. Here, we found that Sec3, one component of exocyst complex, is involved in Drosophila egg chamber development. Loss of sec3 results in egg chamber fusion through the abolishment of cell differentiation. In addition, loss of sec3 increases cell numbers but decreases cell size. These defects phenocopy Notch pathway inactivation. In line with this, loss of sec3 indeed leads to Notch protein accumulation, suggesting that the loss of Sec3 inhibits the delivery of Notch onto the plasma membrane and accumulates inactive Notch in the cytoplasm. Loss of sec3 also leads to the ectopic expression of two Notch pathway target genes, Cut and FasciclinIII, which should normally be downregulated by Notch. Altogether, our study revealed that Sec3 governs egg chamber development through the regulation of Notch, and provides fresh insights into the regulation of oogenesis.

12.
Molecules ; 24(5)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871115

RESUMO

Herein, a convergent, practicable and first total synthesis of the natural product, (±)-methyl salvianolate A, is reported. The key features of the approach are the use of a Horner⁻Wadsworth⁻Emmons reaction and the protection of multiple hydroxyls using silyl protecting groups. The employment of the readily removable silyl protecting groups allows the synthesis of (±)-methyl salvianolate A and its derivatives on a reasonably large scale.


Assuntos
Produtos Biológicos/síntese química , Extratos Vegetais/síntese química , Catálise , Estrutura Molecular , Estereoisomerismo
13.
Org Lett ; 21(7): 2106-2110, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30855147

RESUMO

Reactions of thiocarbonyl fluoride derived from cheap, readily available, and widely used CF3SiMe3, elemental sulfur, and KF with secondary amines and primary amines at room temperature in THF provided a wide variety of thiocarbamoyl fluorides and isothiocyanates in moderate to excellent yields, respectively. The two reactions show broad substrate scope and good functional group tolerance. Moreover, AgSCF3 reacts with secondary/primary amines under KBr at room temperature, affording quantitative thiocarbamoyl fluorides/isothiocyanates, which feature late-stage application.

14.
Plant Physiol ; 179(4): 1723-1738, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718347

RESUMO

Plastid isoprenoids, a diverse group of compounds that includes carotenoids, chlorophylls, tocopherols, and multiple hormones, are essential for plant growth and development. Here, we identified and characterized SEED CAROTENOID DEFICIENT (SCD), which encodes an enzyme that functions in the biosynthesis of plastid isoprenoids in maize (Zea mays). SCD converts 2C-methyl-d-erytrithol 2,4-cyclodiphosphate to 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate in the penultimate step of the methylerythritol phosphate (MEP) pathway. In scd mutants, plant growth and development are impaired and the levels of MEP-derived isoprenoids, such as carotenoids, chlorophylls, and tocopherols, as well as abscisic and gibberellic acids, are reduced in leaves and seeds. This scd metabolic alteration varies among plant tissues and under different light conditions. RNA-sequencing of the scd mutant and wild type identified a limited number of differentially expressed genes in the MEP pathway, although isoprenoid levels were significantly reduced in scd seeds and dark-grown leaves. Furthermore, SCD-overexpressing transgenic lines showed little or no differences in isoprenoid levels, indicating that SCD may be subject to posttranslational regulation or not represent a rate-limiting step in the MEP pathway. These results enhance our understanding of the transcriptomic and metabolic regulatory roles of enzymes in the MEP pathway and of their effects on downstream isoprenoid pathways in various plant tissues and under different light conditions.


Assuntos
Proteínas de Plantas/fisiologia , Zea mays/metabolismo , Carotenoides/metabolismo , Cloroplastos/genética , Cloroplastos/fisiologia , Mapeamento Cromossômico , Clonagem Molecular , Eritritol/análogos & derivados , Eritritol/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Fosfatos Açúcares/genética , Fosfatos Açúcares/metabolismo , Terpenos/metabolismo , Zea mays/genética , Zea mays/crescimento & desenvolvimento
15.
New Phytol ; 221(1): 341-355, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30019753

RESUMO

Group A protein phosphatase 2Cs (PP2Cs) are abscisic acid (ABA) co-receptors that negatively regulate the ABA signaling pathway by inhibiting the downstream SnRK2 protein kinases. It has long been observed that exogenous ABA treatments dramatically induce the expression of group A PP2C genes, but the underlying molecular mechanisms and the biological significance remain largely unknown. Here, by using GUS reporter transgenic lines in which various lengths of ABI1 and ABI2 promoters were used to drive GUS gene expression, we defined the promoter fragments that confer ABA inducibility to ABI1 and ABI2. We further showed that ABRE-binding factors (ABFs), the bZIP family transcription factors, directly bind to the promoters of group A PP2C genes, and mediate rapid induction of their expression on exogenous ABA treatments. Moreover, our data indicated that ABA dramatically induces the expression of ABF genes and the accumulation of endogenous ABF proteins, and that ABFs themselves are involved in this induction, thus providing another layer of ABA regulation towards ABF proteins in addition to the well-characterized ABA-induced phosphorylation by SnRK2 protein kinases. Together, our data demonstrate that ABFs mediate rapid ABA induction of group A PP2C genes, thus playing a role in the negative feedback regulation of ABA signaling.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Retroalimentação Fisiológica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Proc Natl Acad Sci U S A ; 115(50): E11864-E11873, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30478060

RESUMO

Phytochrome A (phyA) is the only plant photoreceptor that perceives far-red light and then mediates various responses to this signal. Phosphorylation and dephosphorylation of oat phyA have been extensively studied, and it was shown that phosphorylation of a serine residue in the hinge region of oat phyA could regulate the interaction of phyA with its signal transducers. However, little is known about the role of the hinge region of Arabidopsis phyA. Here, we report that three sites in the hinge region of Arabidopsis phyA (i.e., S590, T593, and S602) are essential in regulating phyA function. Mutating all three of these sites to either alanines or aspartic acids impaired phyA function, changed the interactions of mutant phyA with FHY1 and FHL, and delayed the degradation of mutant phyA upon light exposure. Moreover, the in vivo formation of a phosphorylated phyA form was greatly affected by these mutations, while our data indicated that the abundance of this phosphorylated phyA form correlated well with the extent of phyA function, thus suggesting a pivotal role of the phosphorylated phyA in inducing the far-red light response. Taking these data together, our study reveals the important role of the hinge region of Arabidopsis phyA in regulating phyA phosphorylation and function, thus linking specific residues in the hinge region to the regulatory mechanisms of phyA phosphorylation.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fitocromo A/química , Fitocromo A/metabolismo , Transporte Ativo do Núcleo Celular , Substituição de Aminoácidos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Luz , Mutagênese Sítio-Dirigida , Fosforilação , Fitocromo/metabolismo , Fitocromo A/genética , Plantas Geneticamente Modificadas , Proteólise , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transcriptoma , Ubiquitina-Proteína Ligases/metabolismo
17.
Plant Cell ; 30(4): 815-834, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618630

RESUMO

The reversible phosphorylation of proteins by kinases and phosphatases is an antagonistic process that modulates many cellular functions. Protein phosphatases are usually negatively regulated by inhibitor proteins. During abscisic acid (ABA) signaling, these inhibitor proteins comprise PYR1/PYL/RCAR ABA receptors, which inhibit the core negative regulators, the clade A type 2C protein phosphatases (PP2Cs). However, it is not known whether these PP2Cs are positively regulated by other proteins. Here, we identified an Arabidopsis thaliana ear1 (enhancer of aba co-receptor1) mutant that exhibits pleiotropic ABA-hypersensitive phenotypes. EAR1 encodes an uncharacterized protein that is conserved in both monocots and dicots. EAR1 interacts with the N-terminal inhibition domains of all six PP2Cs, ABA INSENSITIVE1 (ABI1), ABI2, HYPERSENSITIVE TO ABA1 (HAB1), HAB2, ABA-HYPERSENSITIVE GERMINATION1 (AHG1), and AHG3, during ABA signaling and enhances the activity of PP2Cs both in vitro and in vivo. ABA treatment caused EAR1 to accumulate in the nucleus. These results indicate that EAR1 is a negative regulator of ABA signaling that enhances the activity of PP2Cs by interacting with and releasing the N-terminal autoinhibition of these proteins.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/fisiologia , Mutação , Fenótipo , Fosfoproteínas Fosfatases/genética , Fosforilação , Domínios Proteicos , Proteólise , Transdução de Sinais
18.
Plant Cell ; 30(4): 835-852, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29588390

RESUMO

Phytochrome A (phyA) is the primary plant photoreceptor responsible for perceiving and mediating various responses to far-red (FR) light and is essential for survival in canopy shade. In this study, we identified two Arabidopsis thaliana mutants that grew longer hypocotyls in FR light. Genetic analyses showed that they were allelic and their FR phenotypes were caused by mutations in the gene named TANDEM ZINC-FINGER/PLUS3 (TZP), previously shown to encode a nuclear protein involved in blue light signaling and phyB-dependent regulation of photoperiodic flowering. We show that the expression of TZP is dramatically induced by light and that TZP proteins are differentially modified in different light conditions. Furthermore, we show that TZP interacts with both phyA and FAR-RED ELONGATED HYPOCOTYL1 (FHY1) and regulates the abundance of phyA, FHY1, and ELONGATED HYPOCOTYL5 proteins in FR light. Moreover, our data indicate that TZP is required for the formation of a phosphorylated form of phyA in the nucleus in FR light. Together, our results identify TZP as a positive regulator of phyA signaling required for phosphorylation of the phyA photoreceptor, thus suggesting an important role of phosphorylated phyA in inducing the FR light response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Fitocromo A/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Núcleo Celular/metabolismo , Luz , Proteínas Nucleares , Fosforilação , Fatores de Transcrição/genética , Dedos de Zinco
19.
Hum Genet ; 137(2): 161-173, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29383489

RESUMO

Southeast Asia (SEA) is enriched with a complex history of peopling. Malaysia, which is located at the crossroads of SEA, has been recognized as one of the hubs for early human migration. To unravel the genomic complexity of the native inhabitants of Malaysia, we sequenced 12 samples from 3 indigenous populations from Peninsular Malaysia and 4 native populations from North Borneo to a high coverage of 28-37×. We showed that the Negritos from Peninsular Malaysia shared a common ancestor with the East Asians, but exhibited some level of gene flow from South Asia, while the North Borneo populations exhibited closer genetic affinity towards East Asians than the Malays. The analysis of time of divergence suggested that ancestors of Negrito were the earliest settlers in the Malay Peninsula, whom first separated from the Papuans ~ 50-33 thousand years ago (kya), followed by East Asian (~ 40-15 kya), while the divergence time frame between North Borneo and East Asia populations predates the Austronesian expansion period implies a possible pre-Neolithic colonization. Substantial Neanderthal ancestry was confirmed in our genomes, as was observed in other East Asians. However, no significant difference was observed, in terms of the proportion of Denisovan gene flow into these native inhabitants from Malaysia. Judging from the similar amount of introgression in the Southeast Asians and East Asians, our findings suggest that the Denisovan gene flow may have occurred before the divergence of these populations and that the shared similarities are likely an ancestral component.


Assuntos
DNA Mitocondrial/genética , Variação Genética/genética , Genética Populacional , Genoma Humano/genética , Ásia Sudeste , Bornéu , Fluxo Gênico/genética , Genômica , Migração Humana , Humanos , Malásia , Polimorfismo de Nucleotídeo Único/genética
20.
ACS Appl Mater Interfaces ; 10(10): 9123-9128, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29457452

RESUMO

Multiresponsive fluorescent supramolecular materials are quite interesting, for they combine the multiresponsiveness of supramolecules and the high sensitivity of fluorescent materials. Different from the multiresponsive supramolecular materials based on host-guest interactions, in this report, a supramolecular ionic network was fabricated by 1-(2-aminoethyl)piperazine and citric acids via ionic interactions. Despite the fact that there are no conventional chromophores, the obtained supramolecular ionic material can emit strong fluorescence. Most interestingly, the thin film of this supramolecular ionic material can change its fluorescent intensity in response to four external stimuli, including humidity, triethylamine, acetic acid, and temperature. Beneficial to the supramolecular ionic structure, this multiresponsive fluorescent sensor is self-healable. It is found that a new route has been opened to prepare the multiresponsive fluorescent sensors.

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