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1.
Plant Physiol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833579

RESUMO

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.

2.
Int J Mol Sci ; 23(16)2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-36012372

RESUMO

CK1 casein kinases are well conserved in filamentous fungi. However, their functions are not well characterized in plant pathogens. In Fusarium graminearum, deletion of FgYCK1 caused severe growth defects and loss of conidiation, fertility, and pathogenicity. Interestingly, the Fgyck1 mutant was not stable and often produced fast-growing spontaneous suppressors. Suppressor mutations were frequently identified in the FgBNI4 gene by sequencing analyses. Deletion of the entire FgBNI4 or disruptions of its conserved C-terminal region could suppress the defects of Fgyck1 in hyphal growth and conidiation, indicating the genetic relationship between FgYCK1 and FgBNI4. Furthermore, the Fgyck1 mutant showed defects in polarized growth, cell wall integrity, internalization of FgRho1 and vacuole fusion, which were all partially suppressed by deletion of FgBNI4. Overall, our results indicate a stage-specific functional relationship between FgYCK1 and FgBNI4, possibly via FgRho1 signaling for regulating polarized hyphal growth and cell wall integrity.


Assuntos
Proteínas Fúngicas , Fusarium , Parede Celular/genética , Proteínas Fúngicas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Esporos Fúngicos/genética , Virulência
3.
J Exp Bot ; 72(18): 6365-6381, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34145440

RESUMO

Hypocotyl phototropism is mediated by the phototropins and plays a critical role in seedling morphogenesis by optimizing growth orientation. However, the mechanisms by which phototropism influences morphogenesis require additional study, especially for polyploid crops such as cotton. Here, we found that hypocotyl phototropism was weaker in Gossypium arboreum than in G. raimondii (two diploid cotton species), and LC-MS analysis indicated that G. arboreum hypocotyls had a higher content of abscisic acid (ABA) and a lower content of indole-3-acetic acid (IAA) and bioactive gibberellins (GAs). Consistently, the expression of ABA2, AAO3, and GA2OX1 was higher in G. arboreum than in G. raimondii, and that of GA3OX was lower; these changes promoted ABA synthesis and the transformation of active GA to inactive GA. Higher concentrations of ABA inhibited the asymmetric distribution of IAA across the hypocotyl and blocked the phototropic curvature of G. raimondii. Application of IAA or GA3 to the shaded and illuminated sides of the hypocotyl enhanced and inhibited phototropic curvature, respectively, in G. arboreum. The application of IAA, but not GA, to one side of the hypocotyl caused hypocotyl curvature in the dark. These results indicate that the asymmetric distribution of IAA promotes phototropic growth, and the weakened phototropic curvature of G. arboreum may be attributed to its higher ABA concentrations that inhibit the action of auxin, which is regulated by GA signaling.


Assuntos
Hipocótilo , Fototropismo , Ácido Abscísico , Gossypium/genética , Ácidos Indolacéticos
4.
J Integr Plant Biol ; 62(5): 614-630, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30941890

RESUMO

Both phototropins (phot1 and phot2) and cryptochromes (cry1 and cry2) were proven as the Arabidopsis thaliana blue light receptors. Phototropins predominately function in photomovement, and cryptochromes play a role in photomorphogenesis. Although cryptochromes have been proposed to serve as positive modulators of phototropic responses, the underlying mechanism remains unknown. Here, we report that depleting sucrose from the medium or adding gibberellic acids (GAs) can partially restore the defects in phototropic curvature of the phot1 phot2 double mutants under high-intensity blue light; this restoration does not occur in phot1 phot2 cry1 cry2 quadruple mutants and nph3 (nonphototropic hypocotyl 3) mutants which were impaired phototropic response in sucrose-containing medium. These results indicate that GAs and sucrose antagonistically regulate hypocotyl phototropism in a cryptochromes dependent manner, but it showed a crosstalk with phototropin signaling on NPH3. Furthermore, cryptochromes activation by blue light inhibit GAs synthesis, thus stabilizing DELLAs to block hypocotyl growth, which result in the higher GAs content in the shade side than the lit side of hypocotyl to support the asymmetric growth of hypocotyl. Through modulation of the abundance of DELLAs by sucrose depletion or added GAs, it revealed that cryptochromes have a function in mediating phototropic curvature.


Assuntos
Arabidopsis/metabolismo , Criptocromos/metabolismo , Hipocótilo/metabolismo , Hipocótilo/fisiologia , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Criptocromos/genética , Fototropinas/metabolismo , Fototropinas/fisiologia , Fototropismo/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
5.
Org Biomol Chem ; 17(38): 8745-8748, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31532435

RESUMO

Stable while reactive isatin-derived saturated esters have been utilized as 3-carbon synthons in a base-promoted formal [3 + 2] annulation with N-Boc imines. The developed protocol offers a direct pathway for the rapid and divergent construction of two classes of 3,3'-spirooxindole γ-butyrolactam skeletons that are recognized as the privileged structures of various bioactive compounds. This protocol also has the advantages of mild reaction conditions, scalability and wide reaction scope.

6.
Chemistry ; 24(9): 2103-2108, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29236349

RESUMO

An NHC-catalyzed formal [3+4] annulation of α,ß-unsaturated acylazoliums with protecting-group-free aryl 1,2-diamines was developed for a direct and highly enantioselective synthesis of 4-aryl N-H-free 1,5-benzodiazepin-2-ones. This methodology offers an efficient and rapid access to a wide range of enantioenriched target compounds from easily accessible starting materials. The protocol is also scalable and the desired products can easily undergo subsequent N-functionalization to afford diverse N-substituted derivatives. Additionally, a mechanism was proposed to explain the high enantioselectivity in this process.

7.
J Org Chem ; 83(17): 10430-10435, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30113837

RESUMO

An atom-economic synthesis of useful 1 H-indol-3-yl esters has been demonstrated by an N-heterocyclic carbene (NHC)-catalyzed formal conjugate hydroacylation of 2-phenyl-indol-3-ones with readily accessible aldehydes. This reaction involves a reductive hydride transfer process that was rarely investigated in the field of NHC catalysis. In this process, the hydrogen from the aldehydes was formally transferred to a heteroatom with NHC catalysis for the first time.

8.
Nucleic Acids Res ; 44(6): e55, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26673710

RESUMO

Genome engineering of human cells plays an important role in biotechnology and molecular medicine. In particular, insertions of functional multi-transgene cassettes into suitable endogenous sequences will lead to novel applications. Although several tools have been exploited in this context, safety issues such as cytotoxicity, insertional mutagenesis and off-target cleavage together with limitations in cargo size/expression often compromise utility. Phage λ integrase (Int) is a transgenesis tool that mediates conservative site-specific integration of 48 kb DNA into a safe harbor site of the bacterial genome. Here, we show that an Int variant precisely recombines large episomes into a sequence, term edattH4X, found in 1000 human Long INterspersed Elements-1 (LINE-1). We demonstrate single-copy transgenesis through attH4X-targeting in various cell lines including hESCs, with the flexibility of selecting clones according to transgene performance and downstream applications. This is exemplified with pluripotency reporter cassettes and constitutively expressed payloads that remain functional in LINE1-targeted hESCs and differentiated progenies. Furthermore, LINE-1 targeting does not induce DNA damage-response or chromosomal aberrations, and neither global nor localized endogenous gene expression is substantially affected. Hence, this simple transgene addition tool should become particularly useful for applications that require engineering of the human genome with multi-transgenes.


Assuntos
Técnicas de Transferência de Genes , Engenharia Genética/métodos , Integrases/genética , Plasmídeos/metabolismo , Transgenes , Proteínas Virais/genética , Bacteriófago lambda/química , Bacteriófago lambda/enzimologia , Bacteriófago lambda/genética , Sequência de Bases , Linhagem Celular Tumoral , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Expressão Gênica , Genes Reporter , Genoma Humano , Humanos , Integrases/metabolismo , Elementos Nucleotídeos Longos e Dispersos , Dados de Sequência Molecular , Plasmídeos/química , Proteínas Virais/metabolismo
9.
J Integr Plant Biol ; 60(7): 562-577, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29393576

RESUMO

Two redundant blue-light receptors, known as phototropins (phot1 and phot2), influence a variety of physiological responses, including phototropism, chloroplast positioning, and stomatal opening in Arabidopsis thaliana. Whereas phot1 functions in both low- and high-intensity blue light (HBL), phot2 functions primarily in HBL. Here, we aimed to elucidate phot2-specific functions by screening for HBL-insensitive mutants among mutagenized Arabidopsis phot1 mutants. One of the resulting phot2 signaling associated (p2sa) double mutants, phot1 p2sa2, exhibited phototropic defects that could be restored by constitutively expressing NON-PHOTOTROPIC HYPOCOTYL 3 (NPH3), indicating that P2SA2 was allelic to NPH3. It was observed that NPH3-GFP signal mainly localized to and clustered on the plasma membrane in darkness. This NPH3 clustering on the plasma membrane was not affected by mutations in genes encoding proteins that interact with NPH3, including PHOT1, PHOT2 and ROOT PHOTOTROPISM 2 (RPT2). However, the HBL irradiation-mediated release of NPH3 proteins into the cytoplasm was inhibited in phot1 mutants and enhanced in phot2 and rpt2-2 mutants. Furthermore, HBL-induced hypocotyl phototropism was enhanced in phot1 mutants and inhibited in the phot2 and rpt2-2 mutants. Our findings indicate that phot1 regulates the dissociation of NPH3 from the plasma membrane, whereas phot2 mediates the stabilization and relocation of NPH3 to the plasma membrane to acclimate to HBL.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Luz , Fototropismo/efeitos da radiação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Estiolamento/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Proteínas de Fluorescência Verde/metabolismo , Hipocótilo/metabolismo , Hipocótilo/efeitos da radiação , Mutação/genética , Fototropinas/metabolismo , Plantas Geneticamente Modificadas , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo , Plântula/genética , Plântula/efeitos da radiação , Transdução de Sinais , Frações Subcelulares/metabolismo
10.
BMC Genomics ; 17(1): 633, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27527502

RESUMO

BACKGROUND: Aspergillus westerdijkiae produces ochratoxin A (OTA) in Aspergillus section Circumdati. It is responsible for the contamination of agricultural crops, fruits, and food commodities, as its secondary metabolite OTA poses a potential threat to animals and humans. As a member of the filamentous fungi family, its capacity for enzymatic catalysis and secondary metabolite production is valuable in industrial production and medicine. To understand the genetic factors underlying its pathogenicity, enzymatic degradation, and secondary metabolism, we analysed the whole genome of A. westerdijkiae and compared it with eight other sequenced Aspergillus species. RESULTS: We sequenced the complete genome of A. westerdijkiae and assembled approximately 36 Mb of its genomic DNA, in which we identified 10,861 putative protein-coding genes. We constructed a phylogenetic tree of A. westerdijkiae and eight other sequenced Aspergillus species and found that the sister group of A. westerdijkiae was the A. oryzae - A. flavus clade. By searching the associated databases, we identified 716 cytochrome P450 enzymes, 633 carbohydrate-active enzymes, and 377 proteases. By combining comparative analysis with Kyoto Encyclopaedia of Genes and Genomes (KEGG), Conserved Domains Database (CDD), and Pfam annotations, we predicted 228 potential carbohydrate-active enzymes related to plant polysaccharide degradation (PPD). We found a large number of secondary biosynthetic gene clusters, which suggested that A. westerdijkiae had a remarkable capacity to produce secondary metabolites. Furthermore, we obtained two more reliable and integrated gene sequences containing the reported portions of OTA biosynthesis and identified their respective secondary metabolite clusters. We also systematically annotated these two hybrid t1pks-nrps gene clusters involved in OTA biosynthesis. These two clusters were separate in the genome, and one of them encoded a couple of GH3 and AA3 enzyme genes involved in sucrose and glucose metabolism. CONCLUSIONS: The genomic information obtained in this study is valuable for understanding the life cycle and pathogenicity of A. westerdijkiae. We identified numerous enzyme genes that are potentially involved in host invasion and pathogenicity, and we provided a preliminary prediction for each putative secondary metabolite (SM) gene cluster. In particular, for the OTA-related SM gene clusters, we delivered their components with domain and pathway annotations. This study sets the stage for experimental verification of the biosynthetic and regulatory mechanisms of OTA and for the discovery of new secondary metabolites.


Assuntos
Aspergillus/genética , Genoma Fúngico , Aspergillus/classificação , Aspergillus/metabolismo , Hibridização Genômica Comparativa , Bases de Dados Genéticas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Anotação de Sequência Molecular , Família Multigênica , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Filogenia , Virulência/genética
11.
Int J Mol Sci ; 17(10)2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27690016

RESUMO

Adrenocorticotrophin (ACTH)-secreting pituitary adenoma, also known as Cushing disease (CD), is rare and causes metabolic syndrome, cardiovascular disease and osteoporosis due to hypercortisolism. However, the molecular pathogenesis of CD is still unclear because of a lack of human cell lines and animal models. Here, we study 106 clinical characteristics and gene expression changes from 118 patients, the largest cohort of CD in a single-center. RNA deep sequencing is used to examine genotypic changes in nine paired female ACTH-secreting pituitary adenomas and adjacent nontumorous pituitary tissues (ANPT). We develop a novel analysis linking disease clinical characteristics and whole transcriptomic changes, using Pearson Correlation Coefficient to discover a molecular network mechanism. We report that osteoporosis is distinguished from the phenotype and genotype analysis. A cluster of genes involved in osteoporosis is identified using Pearson correlation coefficient analysis. Most of the genes are reported in the bone related literature, confirming the feasibility of phenotype-genotype association analysis, which could be used in the analysis of almost all diseases. Secreted phosphoprotein 1 (SPP1), collagen type I α 1 chain (COL1A1), 5'-nucleotidase ecto (NT5E), HtrA serine peptidase 1 (HTRA1) and angiopoietin 1 (ANGPT1) and their signalling pathways are shown to be involved in osteoporosis in CD patients. Our discoveries provide a molecular link for osteoporosis in CD patients, and may open new potential avenues for osteoporosis intervention and treatment.

12.
Pituitary ; 17(6): 505-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24379119

RESUMO

BACKGROUND: Adrenocorticotrophic hormone (ACTH)-dependent Cushing's syndrome, called Cushing disease, is caused by a corticotroph tumor of the pituitary gland. Insulin-like growth factor binding protein 6 (IGFBP6), which regulates insulin-like growth factor (IGF) activity and inhibits several IGF2-dependent cancer growths, plays a pivotal role in the tumorigenesis of malignancy, but its roles in ACTH-secreting pituitary adenomas remain unclear. OBJECTIVE: To investigate IGFBP6 expression in ACTH-secreting pituitary adenomas, and its involvement in tumor growth. METHODS: Sporadic ACTH-secreting pituitary adenomas specimens (n = 41) and adjacent non-tumorous pituitary tissues (n = 9) were collected by transphenoidal surgery. IGFBP6 expression was assessed by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and validated by Western blotting. Associations of IGFBP6 expression with maximum tumor diameter or Ki-67 labeling index were evaluated in ACTH-secreting pituitary adenomas. RESULTS: IGFBP6 mRNA and protein expression were both decreased in ACTH-secreting pituitary adenomas, compared to adjacent non-tumorous pituitary tissues (P < 0.01). IGFBP6 expression was correlated inversely with maximum tumor diameter (Rho = -0.53, P < 0.0001) and Ki-67 levels (Rho = -0.52, P < 0.05). Moreover, IGFBP6 downregulation activated PI3 K-AKT-mTOR pathway in ACTH-secreting pituitary adenomas. CONCLUSIONS: IGFBP6 attenuation in ACTH-secreting pituitary adenomas is associated with tumor growth, through activation of PI3K-AKT-mTOR pathway. The finding underlies IGFBP6 roles in Cushing disease and would potentially provide a novel target of medical therapies.


Assuntos
Adenoma Hipofisário Secretor de ACT/metabolismo , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Neoplasias Hipofisárias/metabolismo , Adulto , Biomarcadores Tumorais/metabolismo , Regulação para Baixo , Feminino , Humanos , Técnicas In Vitro , Antígeno Ki-67 , Masculino , Pessoa de Meia-Idade , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Adulto Jovem
13.
Comput Intell Neurosci ; 2022: 2399796, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419506

RESUMO

Aiming at the 1vs1 confrontation problem in a complex environment where obstacles are randomly distributed, the DDPG (deep deterministic policy gradient) algorithm is used to design the maneuver decision-making method of UAVs. Traditional methods generally assume that all obstacles are known globally. In this paper, a UAV airborne lidar detection model is designed, which can effectively solve the problem of obstacle avoidance when facing a large number of unknown obstacles. On the basis of the designed model, the idea of transfer learning is used to transfer the strategy trained by one UAV in a simple task to a new similar task, and the strategy will be used to train the strategy of the other UAV. This method can improve the intelligence of the UAVs in both sides alternately and progressively. The simulation results show that the transfer learning method can speed up the training process and improve the training effect.


Assuntos
Algoritmos , Reforço Psicológico , Simulação por Computador
14.
J Fungi (Basel) ; 8(10)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36294621

RESUMO

Serine/arginine (SR) proteins are essential pre-mRNA splicing factors in eukaryotic organisms. Our previous studies have shownthat the unique SR-specific protein kinase Srk1 is important for RNA splicing and gene transcription in Fusarium graminearum, and interacts with two SR proteins, FgSrp1 and FgSrp2. In this study, we have identified an SR-like protein called Sgh1 in F. graminearum, which is orthologous to budding yeast paralogous Gbp2 and Hrb1. Our data have shownthat the Sgh1 is involved in vegetative growth, conidiation, sexual reproduction, DON synthesis, and plant infection. Moreover, the Sgh1 is mainly localized to the nucleus. RNA-seq analysis has shownthat the expression of over 1100 genes and the splicing efficiency in over 300 introns were affected in the Δsgh1 mutant. Although the RS domain and all three of the RRM domains are important for the Sgh1 functions, only the RS domain is responsible for its nuclear localization. Finally, we verified that the Sgh1 interacts with the unique SR-specific kinase Srk1 in F. graminearum by the yeast-two hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Taken together, our results have revealed that the Sgh1 regulates the fungal development, plant infection, and the pre-mRNA processing, and the RS domain regulates the function of the Sgh1 by modulating its nucleocytoplasmic shuttling.

15.
Plant Physiol Biochem ; 164: 289-298, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34023643

RESUMO

Hypocotyl phototropism is redundantly mediated by phot1 and phot2, two blue light receptor phototropins, under the intensity of blue light>1 µmol m-2 s-1. As light intensity increases, phot1 inhibits the phot2-mediated response. To date, only Arabidopsis Root Phototropism2 (RPT2) has been shown to participate in phot1-mediated inhibition of phototropism. To dissect the signaling network that underlies phot1-mediated inhibition, we carried out a yeast two-hybrid (Y2H) screening assay for RPT2 interacting proteins and identified J-domain protein required for chloroplast accumulation response 1 (JAC1). The interaction between JAC1 and RPT2 was verified by bimolecular fluorescence complementation and Co-IP assays. JAC1 is expressed mainly in cotyledons and hypocotyls. Like RPT2, JAC1 can be induced by blue light, suggesting that it may function similarly to RPT2 in the inhibition of phototropism. Genetic analysis showed that jac1 mutation significantly enhanced the hypocotyl bending of phot1 mutants towards intermediate-intensity blue light, and this effect was inhibited by the constitutive expression of JAC1 in the phot1 jac1 mutant. The phot1 rpt2 double mutant also exhibited enhanced phototropism compared with the phot1 mutant. Taken together, our data clearly demonstrate that JAC1 cooperates with RPT2 to negatively regulate hypocotyl phototropism in plants and may act either downstream of or in parallel with phot1.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Auxilinas , Cloroplastos , Hipocótilo , Luz , Fosfoproteínas , Fototropismo
16.
Front Plant Sci ; 12: 704618, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646282

RESUMO

Phototropins, namely, phototropin 1 (phot1) and phototropin 2 (phot2), mediate chloroplast movement to maximize photosynthetic efficiency and prevent photodamage in plants. Phot1 primarily functions in chloroplast accumulation process, whereas phot2 mediates both chloroplast avoidance and accumulation responses. The avoidance response of phot2-mediated chloroplasts under high-intensity blue light (HBL) limited the understanding of the function of phot1 in the chloroplast accumulation process at the HBL condition. In this study, we showed that the phot2 mutant exhibits a chloroplast accumulation response under HBL, which is defective when the root phototropism 2 (RPT2) gene is mutated in the phot2 background, mimicking the phenotype of the phot1 phot2 double mutant. A further analysis revealed that the expression of RPT2 was induced by HBL and the overexpression of RPT2 could partially enhance the chloroplast accumulation response under HBL. These results confirmed that RPT2 also participates in regulating the phot1-mediated chloroplast accumulation response under HBL. In contrast, RPT2 functions redundantly with neural retina leucine zipper (NRL) protein for chloroplast movement 1 (NCH1) under low-light irradiation. In addition, no chloroplast accumulation response was detected in the phot2 jac1 double mutant under HBL, which has been previously observed in phot2 rpt2 and phot1 phot2 double mutants. Taken together, our results indicated that phot1 mediates the HBL-induced chloroplast accumulation response in an RPT2-dependent manner and is also regulated by j-domain protein required for chloroplast accumulation response 1 (JAC1).

17.
Plant Physiol Biochem ; 135: 51-60, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30500518

RESUMO

Chloroplast movement mediated by the plant-specific phototropin blue light photoreceptors is crucial for plants to cope with fluctuating light conditions. While chloroplasts accumulate at weak light-illuminated areas, chloroplast avoidance response mediated primarily by the phototropin2 (phot2) receptor is induced by strong light illumination. Although extensive studies have been performed on phot2-mediated chloroplast avoidance in the model plant Arabidopsis, little is known on the role of the corresponding PHOT2 orthologs in chloroplast movement in cotton. In this study, we found that chloroplast avoidance movement also occurs in the tetraploid G. hirsutum and two diploid species, G. arboreum and G. raimondii, albeit with distinct features. Further bioinformatics and genetic analysis identified the cotton PHOT2 ortholog, GhPHOT2-1, which retained a conserved role in plant chloroplast avoidance movement under strong blue light. Ghphot2-1was localized in the plasma membrane and formed aggregates after high blue light irradiation. Constitutive expression of GhPHOT2-1 restored chloroplast avoidance and accumulation response, as well as phototropism, and leaf flattening characteristics of the Arabidopsis phot2 or phot1 phot2 mutants. On the contrary, silencing of GhPHOT2-1 by virus-induced gene silencing (VIGS) disrupted high blue light-induced chloroplast avoidance movement and caused photo damage in cotton leaves. Taken together, these findings demonstrated that GhPHOT2-1 is a conserved PHOT2 ortholog in regulating chloroplast avoidance and the other aforementioned phot2-mediated responses, implicating its potential role for improving high light tolerance in cotton cultivars.


Assuntos
Cloroplastos/efeitos da radiação , Genes de Plantas/fisiologia , Gossypium/efeitos da radiação , Fototropinas/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Membrana Celular/fisiologia , Membrana Celular/efeitos da radiação , Cloroplastos/fisiologia , Genes de Plantas/genética , Gossypium/genética , Gossypium/fisiologia , Luz , Fototropinas/genética , Filogenia , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência
18.
Sci Bull (Beijing) ; 64(3): 180-188, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32288967

RESUMO

Influenza is a persistent threat to human health and there is a continuing requirement for updating anti-influenza strategies. Initiated by observations of different endoplasmic reticulum (ER) responses of host to seasonal H1N1 and highly pathogenic avian influenza (HPAI) A H5N1 infections, we identified an alternative antiviral role of tauroursodeoxycholic acid (TUDCA), a clinically available ER stress inhibitor, both in vitro and in vivo. Rather than modulating ER stress in host cells, TUDCA abolished the proton conductivity of viral M2 by disrupting its oligomeric states, which induces inefficient viral infection. We also showed that M2 penetrated cells, whose intracellular uptake depended on its proton channel activity, an effect observed in both TUDCA and M2 inhibitor amantadine. The identification and application of TUDCA as an inhibitor of M2 proton channel will expand our understanding of IAV biology and complement current anti-IAV arsenals.

19.
Sci China Life Sci ; 62(3): 309-320, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28378154

RESUMO

Pulmonary fibrosis, a progressive chronic disease with a high mortality rate, has limited treatment options. Currently, lung transplantation remains the only effective treatment. Here we report that a small RNA, HJT-sRNA-m7, from a Chinese herbal medicine Hong Jing Tian (HJT, RHODIOHAE CRENULATAE RADIX ET RHIZOMA, Rhodiola crenulata) can effectively reduce the expressions of fibrotic hallmark genes and proteins both in alveolar in vitro and in mouse lung tissues in vivo. We also discovered over one hundred oil-soluble chemicals from HJT decoctions, most of which are found in lipid extracts from other Chinese herbals decoctions, including Pu Gong Ying (PGY, TARAXACI HERBA, Taraxacum mongolicum), Chuan Xin Lian (CXL, changed to "ANDROGRAPHIS HERBA, Andrographis paniculata"), and Jin Yin Hua (JYH, lonicera japonica or Honeysuckle). We identified the active component in these decoctions as two forms of phosphocholines, PC (18:0/18:2) and PC (16:0/18:2). These PCs potentially could form liposomes with small RNAs to enter human alveolar and gastric cells. Our experimental results suggest an unprecendent lipid complex route through which botanic small RNA can enter human bodies. Our results provide an innovative treatment strategy for oral delivery of siRNAs as therapeutic medication.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Lipossomos/química , Fosforilcolina/química , Raízes de Plantas/química , Fibrose Pulmonar/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Células A549 , Animais , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Fitoterapia/métodos , Fibrose Pulmonar/metabolismo , RNA de Plantas/química , RNA Interferente Pequeno/química , Rizoma/química
20.
Sci China Life Sci ; 62(3): 321-332, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30238279

RESUMO

Plant-derived microRNAs have recently been reported to function in human blood and tissues. Controversy was immediately raised due to possible contamination and the lack of large sample sizes. Here, we report thousands of unique small RNAs derived from traditional Chinese medicine (TCM) herbs found in human blood cells and mouse lung tissues using a large-scale analysis. We extracted small RNAs from decoctions of 10 TCM plants (Ban Zhi Lian, Chai Hu, Chuan Xin Lian, Di Ding Zi Jin, Huang Qin, Jin Yin Hua, Lian Qiao, Pu Gong Ying, Xia Ku Cao, and Yu Xing Cao) and obtained millions of RNA sequences from each herb. We also obtained RNA-Seq data from the blood cells of humans who consumed herbal decoctions and from the lung tissues of mice administered RNAs from herbal decoctions via oral gavage. We identified thousands of unique small RNA sequences in human blood cells and mouse lung tissues. Some of these identified small RNAs from Chuan Xin Lian and Hong Jing Tian could be mapped to the genomes of the herbs, confirming their TCM plant origin. Small RNAs derived from herbs regulate mammalian gene expression in a sequence-specific manner, and thus are a superior novel class of herbal drug components that hold great potential as oral gene-targeted therapeutics, highlighting the important role of herbgenomics in their development.


Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Pulmão/metabolismo , Plantas Medicinais/genética , RNA de Plantas/genética , Pequeno RNA não Traduzido/genética , Animais , Bupleurum/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Regulação da Expressão Gênica , Humanos , Medicina Tradicional Chinesa/métodos , Medicina Tradicional Chinesa/tendências , Camundongos , Extratos Vegetais/metabolismo , Plantas Medicinais/classificação , RNA de Plantas/sangue , RNA de Plantas/metabolismo , Pequeno RNA não Traduzido/sangue , Pequeno RNA não Traduzido/metabolismo , Scutellaria baicalensis/metabolismo , Análise de Sequência de RNA/métodos
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