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1.
bioRxiv ; 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39149359

RESUMEN

Characterization of shared patterns of RNA expression between genes across conditions has led to the discovery of regulatory networks and novel biological functions. However, it is unclear if such coordination extends to translation, a critical step in gene expression. Here, we uniformly analyzed 3,819 ribosome profiling datasets from 117 human and 94 mouse tissues and cell lines. We introduce the concept of Translation Efficiency Covariation (TEC), identifying coordinated translation patterns across cell types. We nominate potential mechanisms driving shared patterns of translation regulation. TEC is conserved across human and mouse cells and helps uncover gene functions. Moreover, our observations indicate that proteins that physically interact are highly enriched for positive covariation at both translational and transcriptional levels. Our findings establish translational covariation as a conserved organizing principle of mammalian transcriptomes.

2.
Front Microbiol ; 14: 1257442, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38152372

RESUMEN

Phosphorus (P) deficiency is a predominant constraint on plant growth in acidified soils, largely due to the sequestration of P by toxic aluminum (Al) compounds. Indigenous phosphorus-solubilizing bacteria (PSBs) capable of mobilizing Al-P in these soils hold significant promise. A novel Al-P-solubilizing strain, Al-P Nguyenibacter sp. L1, was isolated from the rhizosphere soil of healthy Lespedeza bicolor plants indigenous to acidic terrains. However, our understanding of the genomic landscape of bacterial species within the genus Nguyenibacter remains in its infancy. To further explore its biotechnological potentialities, we sequenced the complete genome of this strain, employing an amalgamation of Oxford Nanopore ONT and Illumina sequencing platforms. The resultant genomic sequence of Nguyenibacter sp. L1 manifests as a singular, circular chromosome encompassing 4,294,433 nucleotides and displaying a GC content of 66.73%. The genome was found to host 3,820 protein-coding sequences, 12 rRNAs, and 55 tRNAs. Intriguingly, annotations derived from the eggNOG and KEGG databases indicate the presence of genes affiliated with phosphorus solubilization and nitrogen fixation, including iscU, glnA, and gltB/D associated with nitrogen fixation, and pqqBC associated with inorganic phosphate dissolution. Several bioactive secondary metabolite genes in the genome, including pqqCDE, phytoene synthase and squalene synthase predicted by antiSMASH. Moreover, we uncovered a complete metabolic pathway for ammonia, suggesting an ammonia-affinity property inherent to Nguyenibacter sp. L1. This study verifies the nitrogen-fixing and phosphate-dissolving abilities of Nguyenibacter sp. L1 at the molecular level through genetic screening and analysis. The insights gleaned from this study offer strategic guidance for future strain enhancement and establish a strong foundation for the potential incorporation of this bacterium into agricultural practices.

3.
Genes (Basel) ; 14(11)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-38002969

RESUMEN

The MYB (v-Myb avivan myoblastsis virus oncogene homolog) transcription factor family is one of the largest families of plant transcription factors which plays a vital role in many aspects of plant growth and development. MYB-related is a subclass of the MYB family. Fifty-nine Arabidopsis thaliana MYB-related (AtMYB-related) genes have been identified. In order to understand the functions of these genes, in this review, the promoters of AtMYB-related genes were analyzed by means of bioinformatics, and the progress of research into the functions of these genes has been described. The main functions of these AtMYB-related genes are light response and circadian rhythm regulation, root hair and trichome development, telomere DNA binding, and hormone response. From an analysis of cis-acting elements, it was found that the promoters of these genes contained light-responsive elements and plant hormone response elements. Most genes contained elements related to drought, low temperature, and defense and stress responses. These analyses suggest that AtMYB-related genes may be involved in A. thaliana growth and development, and environmental adaptation through plant hormone pathways. However, the functions of many genes do not occur independently but instead interact with each other through different pathways. In the future, the study of the role of the gene in different pathways will be conducive to a comprehensive understanding of the function of the gene. Therefore, gene cloning and protein functional analyses can be subsequently used to understand the regulatory mechanisms of AtMYB-related genes in the interaction of multiple signal pathways. This review provides theoretical guidance for the follow-up study of plant MYB-related genes.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Estudios de Seguimiento , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Oncogenes
4.
Acta Crystallogr F Struct Biol Commun ; 79(Pt 8): 217-223, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37565839

RESUMEN

Members of the GCN5-related N-acetyltransferase (GNAT) family are found in all domains of life and are involved in processes ranging from protein synthesis and gene expression to detoxification and virulence. Due to the variety of their macromolecular targets, GNATs are a highly diverse family of proteins. Currently, 3D structures of only a small number of GNAT representatives are available and thus the family remains poorly characterized. Here, the crystal structure of the guanidine riboswitch-associated GNAT from Lactobacillus curiae (LcGNAT) that acetylates canavanine, a structural analogue of arginine with antimetabolite properties, is reported. LcGNAT shares the conserved fold of the members of the GNAT superfamily, but does not contain an N-terminal ß0 strand and instead contains a C-terminal ß7 strand. Its P-loop, which coordinates the pyrophosphate moiety of the acetyl-coenzyme A cosubstrate, is degenerated. These features are shared with its closest homologues in the polyamine acetyltransferase subclass. Site-directed mutagenesis revealed a central role of the conserved residue Tyr142 in catalysis, as well as the semi-conserved Tyr97 and Glu92, suggesting that despite its individual substrate specificity LcGNAT performs the classical reaction mechanism of this family.


Asunto(s)
Acetiltransferasas , Acetiltransferasas/química , Cristalografía por Rayos X
5.
Front Genet ; 14: 1049608, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139239

RESUMEN

The application of plant growth-promoting bacteria (PGPB) is vital for sustainable agriculture with continuous world population growth and an increase in soil salinity. Salinity is one of the severe abiotic stresses which lessens the productivity of agricultural lands. Plant growth-promoting bacteria are key players in solving this problem and can mitigate salinity stress. The highest of reported halotolerant Plant growth-promoting bacteria belonged to Firmicutes (approximately 50%), Proteobacteria (40%), and Actinobacteria (10%), respectively. The most dominant genera of halotolerant plant growth-promoting bacteria are Bacillus and Pseudomonas. Currently, the identification of new plant growth-promoting bacteria with special beneficial properties is increasingly needed. Moreover, for the effective use of plant growth-promoting bacteria in agriculture, the unknown molecular aspects of their function and interaction with plants must be defined. Omics and meta-omics studies can unreveal these unknown genes and pathways. However, more accurate omics studies need a detailed understanding of so far known molecular mechanisms of plant stress protection by plant growth-promoting bacteria. In this review, the molecular basis of salinity stress mitigation by plant growth-promoting bacteria is presented, the identified genes in the genomes of 20 halotolerant plant growth-promoting bacteria are assessed, and the prevalence of their involved genes is highlighted. The genes related to the synthesis of indole acetic acid (IAA) (70%), siderophores (60%), osmoprotectants (80%), chaperons (40%), 1-aminocyclopropane-1-carboxylate (ACC) deaminase (50%), and antioxidants (50%), phosphate solubilization (60%), and ion homeostasis (80%) were the most common detected genes in the genomes of evaluated halotolerant plant growth-promoting and salinity stress-alleviating bacteria. The most prevalent genes can be applied as candidates for designing molecular markers for screening of new halotolerant plant growth-promoting bacteria.

6.
Acta Trop ; 243: 106923, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37080265

RESUMEN

Fleas are important ectoparasites and vectors associated with a wide range of pathogenic diseases, posing threats to public health concerns, especially cat fleas that spread worldwide. Understanding the microbial components is essential due to cat fleas are capable of transmitting pathogens to humans, causing diseases like plague and murine typhus. In the present study, metagenomic next-generation sequencing was applied to obtain the complete microbiota and related functions in the gut of Ctenocephalides felis. A total of 1,870 species was taxonomically recognized including 1,407 bacteria, 365 eukaryotes, 69 viruses, and 29 archaea. Proteobacteria was the dominant phylum among the six samples. Pathogens Rickettsia felis, Acinetobacter baumannii, Coxiella burnetii, and Anaplasma phagocytophilum were taxonomically identified and had high abundances in all samples. The resistance gene MexD was predominant in microbial communities of all cat fleas. We also performed epidemiological surveys of pathogens R. felis, A. baumannii, C. burnetii, and A. phagocytophilum among 165 cat fleas collected from seven provinces in China, while only the DNAs of R. felis (38/165, 23.03%) and C. burnetii (2/165, 1.21%) were obtained. The data provide new insight and understanding of flea intestinal microbiota and support novel information for preventing and controlling fleas and their transmitted diseases.


Asunto(s)
Enfermedades de los Gatos , Ctenocephalides , Felis , Infestaciones por Pulgas , Rickettsia felis , Siphonaptera , Animales , Humanos , Ratones , Gatos , Ctenocephalides/genética , Infestaciones por Pulgas/veterinaria , Infestaciones por Pulgas/parasitología , Rickettsia felis/genética , Bacterias/genética
7.
Bioresour Technol ; 377: 128914, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36940881

RESUMEN

Side-stream reactor (SSR), as an in-situ sludge reduction process with high sludge reduction efficiency (SRE) and less negative impact on effluent, has been widely researched. In order to reduce cost and promote large-scale application, the anaerobic/anoxic/micro-aerobic/oxic bioreactor coupled with micro-aerobic SSR (AAMOM) was used to investigate nutrient removal and SRE under short hydraulic retention time (HRT) of SSR. When HRT of SSR was 4 h, AAMOM system achieved 30.41% SRE, while maintaining carbon and nitrogen removal efficiency. Micro-aerobic in mainstream accelerated the hydrolysis of particulate organic matter (POM) and promoted denitrification. Micro-aerobic in side-stream increased cell lysis and ATP dissipation, thus increasing SRE. Microbial community structure indicated that the cooperative interactions among hydrolytic, slow growing, predatory and fermentation bacteria played key roles in improving SRE. This study confirmed that SSR coupled micro-aerobic was a promising and practical process, which could benefit nitrogen removal and sludge reduction in municipal wastewater treatment plants.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas del Alcantarillado/microbiología , Anaerobiosis , Reactores Biológicos/microbiología , Fermentación , Nitrógeno
8.
Environ Sci Pollut Res Int ; 30(8): 21548-21564, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36272007

RESUMEN

The genus Enterobacter is widely recognized for its biotechnology potential in improving soil environment and crop growth promotion. To further explore these biotechnological potentials, we sequenced and analyzed the whole genome of Enterobacter cloacae Rs-2. The analysis showed that the total length of the Rs-2 genome was 6,965,070,514 bp, and GC content was 55.80%; the annotation results of GO and COG databases showed that the genome contains a variety of growth-promoting genes, such as iscU, glnA, glnB (nitrogen fixation); iucABCD (siderophore synthesis) and fepA, fcuA, fhuA, and pfeA, etc. (siderophore transport); ipdC (secreted IAA) and gcd, pqqBCDEF (dissolved phosphorus), etc. No pathogenic factors such as virulence genes were found. The application of Rs-2 as a soil inoculant in pot experiments showed great potential for growth promotion. This study proved the plant growth-promoting ability of Rs-2 at the molecular level through genetic screening and analysis, which provided guidance for the further improvement of the strain and laid a foundation for its application in agricultural production.


Asunto(s)
Enterobacter cloacae , Sideróforos , Enterobacter cloacae/genética , Enterobacter/genética , Fósforo , Desarrollo de la Planta , Suelo
9.
Parasitol Res ; 122(2): 441-450, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36471092

RESUMEN

Several calcium-binding proteins including calcium-dependent protein kinases play important roles in several facets of the intracellular infection cycle of the apicomplexan protozoan parasite Toxoplasma gondii. However, the role of the calcium-binding epidermal growth factor (EGF) domain-containing proteins (CBDPs) remains poorly understood. In this study, we examined the functions of four CBDP genes in T. gondii RH strain of type I by generating knock-out strains using CRISPR-Cas9 system. We investigated the ability of mutant strains deficient in CBDP1, CBDP2, CBDP3, or CBDP4 to form plaques, replicate intracellularly, and egress from the host cells. The results showed that no definite differences between any of these four CBDP mutant strains and the wild-type strain in terms of their ability to form plaques, intracellular replication, and egress. Additionally, CBDP mutants did not exhibit any significant attenuated virulence compared to the wild-type strain in mice. The expression profiles of CBDP2-4 genes were conserved among T. gondii strains of different genotypes, life cycle stages, and developmental forms. Whether other CBDP genes play any roles in the pathogenicity of T. gondii strains of different genotypes remains to be elucidated.


Asunto(s)
Parásitos , Toxoplasma , Animales , Ratones , Virulencia , Parásitos/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Calcio/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo
10.
Yi Chuan ; 44(8): 682-694, 2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-36384667

RESUMEN

Orphan genes are located in a special evolutionary branch and have no significant sequence similarity with any other identified genes. Orphan genes are prevalent in every species, comparative genomics analyses found that all sequenced species contained a portion of orphan genes, and the number of orphan genes obtained by distinct screening conditions is different. Orphan genes are often associated with various stress responses, species-specific evolution and substance metabolism regulation. However, most of the orphan genes have not been well annotated or even have no recognizable functional domains, which brings some difficulties to the functional characterization of orphan genes. Compared with conserved genes, there is less research on orphan genes, which leads to the possibility that the importance of orphan genes may be "unrewarded". In this review, we summarize the origin and evolution of orphan genes, plant orphan gene screening and functions, and analyse the existing challenges and future research priorities and solutions, which provide theoretical basis for the study of orphan gene function and action mechanisms.


Asunto(s)
Evolución Molecular , Genes de Plantas , Especificidad de la Especie , Secuencia de Bases
11.
Front Genet ; 12: 678625, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34322153

RESUMEN

Sphingonotus Fieber, 1852 (Orthoptera: Acrididae), is a grasshopper genus comprising approximately 170 species, all of which prefer dry environments such as deserts, steppes, and stony benchlands. In this study, we aimed to examine the adaptation of grasshopper species to arid environments. The genome size of Sphingonotus tsinlingensis was estimated using flow cytometry, and the first high-quality full-length transcriptome of this species was produced. The genome size of S. tsinlingensis is approximately 12.8 Gb. Based on 146.98 Gb of PacBio sequencing data, 221.47 Mb full-length transcripts were assembled. Among these, 88,693 non-redundant isoforms were identified with an N50 value of 2,726 bp, which was markedly longer than previous grasshopper transcriptome assemblies. In total, 48,502 protein-coding sequences were identified, and 37,569 were annotated using public gene function databases. Moreover, 36,488 simple tandem repeats, 12,765 long non-coding RNAs, and 414 transcription factors were identified. According to gene functions, 61 cytochrome P450 (CYP450) and 66 heat shock protein (HSP) genes, which may be associated with drought adaptation of S. tsinlingensis, were identified. We compared the transcriptomes of S. tsinlingensis and two other grasshopper species which were less tolerant to drought, namely Mongolotettix japonicus and Gomphocerus licenti. We observed the expression of CYP450 and HSP genes in S. tsinlingensis were higher. We produced the first full-length transcriptome of a Sphingonotus species that has an ultra-large genome. The assembly characteristics were better than those of all known grasshopper transcriptomes. This full-length transcriptome may thus be used to understand the genetic background and evolution of grasshoppers.

12.
J Environ Manage ; 295: 113088, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34174687

RESUMEN

In-situ sludge reduction plays a significant role in reducing excess sludge production. This study investigated the role of beneficial microorganisms (BM) in the anoxic-oxic-settling-anoxic (A-OSA) process associated with the in-situ sludge reduction efficiency under synthetic landfill leachate treatment. The rates of excess sludge reduction with the inoculation of BM increased up to 53.6% (calculated as total suspended solids) and 38.3% (calculated as total volume), respectively. Side-stream reactors, as important components of the A-OSA process, were further studied to explore change of parameters related to in-situ sludge reduction. With the inoculation of BM, the release and conversion of extracellular polymeric substances and the dehydrogenase activity (increasing rate = 60.9%) were increased. Species richness and microbial diversity, as well as the microbial community composition (e.g., hydrolytic and fermentative bacteria), were improved via bioaugmentation. Moreover, potential gene functions of microorganisms were positively regulated and the abundance of gene expressions (e.g., nirK, norB) for in-situ sludge reduction could be improved.


Asunto(s)
Aguas del Alcantarillado , Contaminantes Químicos del Agua , Anaerobiosis , Reactores Biológicos , Consorcios Microbianos , Eliminación de Residuos Líquidos
13.
Bioresour Technol ; 336: 125317, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34087730

RESUMEN

In this study, an integrated investigation to the microbial activities, extracellular polymeric substance (EPS), microbial community and function of anammox granular sludge (AnGS) was performed.Results showed that AnGS at 0.5-1.0 mm had the highest average specific anammox activity (SAA) of 345.9 mg NH4+-N·gVSS-1·d-1, but AnGS at 1.0-1.5 mm with higher SAA might lead to better nitrogen removal efficiency. The content of slime EPS and SAA achieved positively correlation with R2 of 98.11%, while protein/polysaccharide ratio of slime EPS and sludge volume index achieved negatively correlation with R2 of 99.13%. Cadidatus Broccadia and Denitratisoma were positive correlations and most abundant in AnGS 0.5-1.0 mm of 20% and AnGS 1.0-1.5 mm of 37%, respectively. AnGS at 0.5-1.0 mm exhibited higher energy metabolism which mostly contributed to produce protein. The study provides new insights into the mechanisms of AnGS about 1 mm playing more important role in nitrogen removal performance.


Asunto(s)
Nitrógeno , Aguas del Alcantarillado , Reactores Biológicos , Desnitrificación , Matriz Extracelular de Sustancias Poliméricas , Oxidación-Reducción
15.
Cell Biosci ; 10: 97, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32817785

RESUMEN

Sex differences are prevalent in normal development, physiology and disease pathogeneses. Recent studies have demonstrated that mosaic loss of Y chromosome and aberrant activation of its genes could modify the disease processes in male biased manners. This mini review discusses the nature of the genes on the human Y chromosome and identifies two general categories of genes: those sharing dosage-sensitivity functions with their X homologues and those with testis-specific expression and functions. Mosaic loss of the former disrupts the homeostasis important for the maintenance of health while aberrant activation of the latter promotes pathogenesis in non-gonadal tissues, thereby contributing to genetic predispositions to diseases in men.

16.
Comput Struct Biotechnol J ; 18: 1722-1734, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32670511

RESUMEN

Metagenomic sequencing of complete microbial communities has greatly enhanced our understanding of the taxonomic composition of microbiotas. This has led to breakthrough developments in bioinformatic disciplines such as assembly, gene clustering, metagenomic binning of species genomes and the discovery of an incredible, so far undiscovered, taxonomic diversity. However, functional annotations and estimating metabolic processes from single species - or communities - is still challenging. Earlier approaches relied mostly on inferring the presence of key enzymes for metabolic pathways in the whole metagenome, ignoring the genomic context of such enzymes, resulting in the 'bag-of-genes' approach to estimate functional capacities of microbiotas. Here, we review recent developments in metagenomic bioinformatics, with a special focus on emerging technologies to simulate and estimate metabolic information, that can be derived from metagenomic assembled genomes. Genome-scale metabolic models can be used to model the emergent properties of microbial consortia and whole communities, and the progress in this area is reviewed. While this subfield of metagenomics is still in its infancy, it is becoming evident that there is a dire need for further bioinformatic tools to address the complex combinatorial problems in modelling the metabolism of large communities as a 'bag-of-genomes'.

17.
Front Microbiol ; 11: 399, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32318029

RESUMEN

Toxoplasma gondii (T. gondii) is an obligate intracellular apicomplexan protozoan that can parasitize most warm-blooded animals and cause severe diseases in immunocompromised individuals or fetal abnormalities in pregnant woman. The treatment of toxoplamosis has been limited by effective drugs. Our previous work indicated that the novel gene wx2 of T. gondii may serve as a vaccine antigen candidate. To further investigate the molecular functions of wx2 in highly virulent T. gondii (RH strain), a wx2 gene deletion mutant RH strain (KO-wx2) was established using CRISPR-Cas9. The phynotype of KO-wx2 was analyzed by plaque, invasion, and replication assays in vitro as well as in vivo virulence assays. The results indicated that the targeted deletion of the wx2 gene significantly inhibited in vitro parasite growth and replication in the host cells as well as attenuated parasite virulence in the mouse model. Notably, the percentage of pro-inflammatory factors of interferon gamma (IFN-γ) and interlukin-17A (IL-17A) and anti-inflammatory factor of interlukin-10 (IL-10) in the lymph nodes were upregulated in mice infected with the KO-wx2 strain. Our data suggested that the wx2 gene plays an important role in the process of the parasite's life cycle and virulence in mice. In addition, it also plays an important role in the host's immunity reaction, mainly via Th1 and Th17 cellular immunity, not Th2.

18.
Reprod Biol Endocrinol ; 17(1): 52, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31288842

RESUMEN

BACKGROUND: Recurrent pregnancy loss (RPL) refers to two or more spontaneous abortions that occur consecutively with the same spouse. RPL severely affects human reproduction health, and causes extreme physical and mental suffering to patients and their families. METHODS: We used isobaric tags for relative and absolute quantitation (iTRAQ), which was coupled with liquid chromatography mass spectrometry (LC-MS) proteomic analysis, in order to identify differentially expressed proteins. Moreover, we used western blot to analyze differentially expressed proteins. RESULTS: Of the 2350 non-redundant proteins identified, 38 proteins were significantly altered and were identified as potential biomarkers for RPL. The protein-protein interaction network constructed using GeneMANIA revealed that 35.55% displayed similar co-expression, 30.87% were predicted, and 20.95% had physical interaction characteristics. Based on Gene ontology classification and KEGG pathway enrichment analyses, the majority of these differentially expressed proteins were found to be related to biological regulation, metabolic and cellular processes, protein binding and different enzymes activities, as well as disorder of fat and glucose metabolic pathways. It is noteworthy that three metabolism related biomarkers (HK1, ACLY, and FASN) were further confirmed through western blot analysis. CONCLUSIONS: These results suggest that these differentially expressed proteins may be used as biomarkers for RPL, and related signaling pathways may play crucial roles in male induced RPL.


Asunto(s)
Aborto Habitual/metabolismo , Proteoma/metabolismo , Proteómica/métodos , Espermatozoides/metabolismo , Aborto Habitual/genética , Cromatografía Liquida , Femenino , Perfilación de la Expresión Génica/métodos , Ontología de Genes , Humanos , Masculino , Embarazo , Mapas de Interacción de Proteínas/genética , Proteoma/genética , Transducción de Señal/genética , Espectrometría de Masas en Tándem
19.
Int J Mol Sci ; 20(9)2019 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-31035490

RESUMEN

C-repeat binding factor/dehydration-responsive element (CBF/DRE) transcription factors (TFs) participate in a variety of adaptive mechanisms, and are involved in molecular signaling and abiotic stress tolerance in plants. In pear (Pyrus pyrifolia) and other rosaceous crops, the independent evolution of CBF subfamily members requires investigation to understand the possible divergent functions of these proteins. In this study, phylogenetic analysis divided six PpyCBFs from the Asian pear genome into three clades/subtypes, and collinearity and phylogenetic analyses suggested that PpyCBF3 was the mother CBF. All PpyCBFs were found to be highly expressed in response to low temperature, salt, drought, and abscisic acid (ABA) as well as bud endodormancy, similar to PpyCORs (PpyCOR47, PpyCOR15A, PpyRD29A, and PpyKIN). Transcript levels of clade II PpyCBFs during low temperature and ABA treatments were higher than those of clades I and III. Ectopic expression of PpyCBF2 and PpyCBF3 in Arabidopsis enhanced its tolerance against abiotic stresses, especially to low temperature in the first case and salt and drought stresses in the latter, and resulted in lower reactive oxygen species (ROS) and antioxidant gene activities compared with the wild type. The increased expression of endogenous ABA-dependent and -independent genes during normal conditions in PpyCBF2- and PpyCBF3-overexpressing Arabidopsis lines suggested that PpyCBFs were involved in both ABA-dependent and -independent pathways. All PpyCBFs, especially the mother CBF, had high transactivation activities with 6XCCGAC binding elements. Luciferase and Y1H assays revealed the existence of phylogenetically and promoter-dependent conserved CBF-COR cascades in the pear. The presence of a previously identified CCGA binding site, combined with the results of mutagenesis of the CGACA binding site of the PpyCOR15A promoter, indicated that CGA was a core binding element of PpyCBFs. In conclusion, PpyCBF TFs might operate redundantly via both ABA-dependent and -independent pathways, and are strongly linked to abiotic stress signaling and responses in the Asian pear.


Asunto(s)
Filogenia , Proteínas de Plantas/genética , Pyrus/clasificación , Pyrus/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Sitios de Unión , Frío , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Latencia en las Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Unión Proteica , Pyrus/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Estrés Fisiológico , Transcripción Genética
20.
Plant Pathol J ; 34(5): 412-425, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30369851

RESUMEN

The Hfq protein is a global small RNA chaperone that interacts with regulatory bacterial small RNAs (sRNA) and plays a role in the post-transcriptional regulation of gene expression. The roles of Hfq in the virulence and pathogenicity of several infectious bacteria have been reported. This study was conducted to elucidate the functions of two hfq genes in Burkholderia glumae, a causal agent of rice grain rot. Therefore, mutant strains of the rice-pathogenic B. glumae BGR1, targeting each of the two hfq genes, as well as the double defective mutant were constructed and tested for several phenotypic characteristics. Bacterial swarming motility, toxoflavin production, virulence in rice, siderophore production, sensitivity to H2O2, and lipase production assays were conducted to compare the mutant strains with the wild-type B. glumae BGR1 and complementation strains. The hfq1 gene showed more influence on bacterial motility and toxoflavin production than the hfq2 gene. Both genes were involved in the full virulence of B. glumae in rice plants. Other biochemical characteristics such as siderophore production and sensitivity to H2O2 induced oxidative stress were also found to be regulated by the hfq1 gene. However, lipase activity was shown to be unassociated with both tested genes. To the best of our knowledge, this is the first study to elucidate the functions of two hfq genes in B. glumae. Identification of virulence-related factors in B. glumae will facilitate the development of efficient control measures.

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