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1.
Plant Physiol Biochem ; 212: 108727, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761548

RESUMO

Phosphatidylserine (PS) is an important lipid signaling required for plant growth regulation and salt stress adaptation. However, how PS positively regulate plant salt tolerance is still largely unknown. In this study, IbPSS1-overexpressed sweetpotato plants that exhibited overproduction of PS was employed to explore the mechanisms underlying the PS stimulation of plant salt tolerance. The results revealed that the IbPSS1-overexpressed sweetpotato accumulated less Na+ in the stem and leaf tissues compared with the wild type plants. Proteomic profile of roots showed that lignin synthesis-related proteins over-accumulated in IbPSS1-overexpressed sweetpotato. Correspondingly, the lignin content was enhanced but the influx of Na + into the stele was significantly blocked in IbPSS1-overexpressed sweetpotato. The results further revealed that ethylene synthesis and signaling related genes were upregulated in IbPSS1-overexpressed sweetpotato. Ethylene imaging experiment revealed the enhancement of ethylene mainly localized in the root stele. Inhibition of ethylene synthesis completely reversed the PS-overproduction induced lignin synthesis and Na+ influx pattern in stele tissues. Taken together, our findings demonstrate a mechanism by which PS regulates ethylene signaling and lignin synthesis in the root stele, thus helping sweetpotato plants to block the loading of Na+ into the xylem and to minimize the accumulation of Na+ in the shoots.


Assuntos
Etilenos , Ipomoea batatas , Lignina , Proteínas de Plantas , Raízes de Plantas , Tolerância ao Sal , Transdução de Sinais , Etilenos/metabolismo , Etilenos/biossíntese , Lignina/metabolismo , Lignina/biossíntese , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Tolerância ao Sal/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Fosfatidilserinas/metabolismo , Sódio/metabolismo
2.
Genes (Basel) ; 15(3)2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38540413

RESUMO

Sweetpotato (Ipomoea batatas L.) is a strategic crop with both economic and energy value. However, improving sweetpotato varieties through traditional breeding approaches can be a time-consuming and labor-intensive process due to the complex genetic nature of sweetpotato as a hexaploid species (2n = 6x = 90). Double haploid (DH) breeding, based on in vivo haploid induction, provides a new approach for rapid breeding of crops. The success of haploid induction can be achieved by manipulating specific genes. Two of the most critical genes, DMP (DUF679 membrane proteins) and MTL (MATRILINEAL), have been shown to induce haploid production in several species. Here, we identified and characterized DMP and MTL genes in sweetpotato using gene family analysis. In this study, we identified 5 IbDMPs and 25 IbpPLAs. IbDMP5 and IbPLAIIs (IbPLAIIκ, IbPLAIIλ, and IbPLAIIµ) were identified as potential haploid induction (HI) genes in sweetpotato. These results provide valuable information for the identification and potential function of HI genes in sweetpotato and provide ideas for the breeding of DH lines.


Assuntos
Ipomoea batatas , Ipomoea batatas/genética , Melhoramento Vegetal
3.
Environ Monit Assess ; 194(8): 559, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35781138

RESUMO

The quantitative evaluation of water conservation in the Luoyang area can provide a basis for decision-making on regional water resources development and utilization, ecological environmental protection, and economic development planning. Based on the SWAT model and alternative engineering method, the water conservation and its service value in Luoyang region from 2009 to 2018 were assessed and the reasons for their spatial and temporal changes were analyzed. The results show that during the period of 2009-2018, the total water connotation and its service value reached the highest in 2014, with 16,927,100 m3 and 103 million yuan, respectively; the total water connotation and its service value reached the lowest in 2011, with 7,073,500 m3 and 43,224,000 yuan, respectively. Forest ecosystems have a strong water retention and storage capacity, and the highest water conservation and service value. Precipitation is the most important factor influencing water conservation and service value. The value of water-supporting services per unit area of ecosystem in Luoyang area is forest, grassland, arable land, and urban in descending order.


Assuntos
Conservação dos Recursos Hídricos , Ecossistema , Conservação dos Recursos Naturais , Monitoramento Ambiental , Água
4.
Genome ; 65(6): 331-339, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35254885

RESUMO

Cultivated sweetpotato [Ipomoea batatas (L.) Lam.] from the family Convolvulaceae is a hexaploid species with 2n = 6x = 90 and has been controversial regarding its nature as an autopolyploid arising within a species or an allopolyploid forming between species. Here, we developed oligonucleotide-based painting probes for two chromosomes of I. nil, a model diploid Ipomoea species. Using these probes, we revealed the pairing behavior of homoeologous chromosomes in I. batatas and its two possible polyploid ancestral species, tetraploid I. tabascana (2n = 4x = 60) and hexaploid I. trifida (2n = 6x = 90). Chromosome painting analysis revealed a high percentage of quadrivalent formation in zygotene-pachytene cells of I. tabascana, which supported that I. tabascana was an autotetraploid likely derived by doubling of structurally similar and homologous genomes rather than a hybrid between I. batatas and I. trifida (2x). A high frequency of hexavalent/bivalent and tetravalent pairing was observed in I. trifida (6x) and I. batatas. However, the percentage of hexavalent pairing in I. trifida (6x) was far higher than that in I. batatas. Thus, the present results tend to support that I. trifida (6x) is an autohexaploid, while I. batatas is more likely to be a segmental allohexaploid.


Assuntos
Ipomoea batatas , Ipomoea , Coloração Cromossômica , Genômica , Ipomoea/genética , Ipomoea batatas/genética , Poliploidia
5.
Front Plant Sci ; 13: 1091620, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714734

RESUMO

Two-component system (TCS), which comprises histidine kinases (HKs), histidine phosphotransfer proteins (HPs), and response regulators (RRs), plays essential roles in regulating plant growth, development, and response to various environmental stimuli. TCS genes have been comprehensively identified in various plants, while studies on the genome-wide identification and analysis of TCS in sweet potato were still not reported. Therefore, in this study, a total of 90 TCS members consisting of 20 HK(L)s, 11 HPs, and 59 RRs were identified in the genome of Ipomoea batatas. Furthermore, their gene structures, conserved domains, and phylogenetic relationships were analyzed in detail. Additionally, the gene expression profiles in various organs were analyzed, and response patterns to adverse environmental stresses were investigated. The results showed that these 90 TCS genes were mapped on 15 chromosomes with a notably uneven distribution, and the expansion of TCS genes in sweet potato was attributed to both segmental and tandem duplications. The majority of the TCS genes showed distinct organ-specific expression profiles, especially in three types of roots (stem roots, fibrous roots, tuberous roots). Moreover, most of the TCS genes were either induced or suppressed upon treatment with abiotic stresses (drought, salinity, cold, heat) and exogenous phytohormone abscisic acid (ABA). In addition, the yeast-two hybrid system was used to reveal the HK-HP-RR protein-protein interactions. IbHP1, IbHP2, IbHP4, and IbHP5 could interact with three HKs (IbHK1a, IbHK1b, and IbHK5), and also interact with majority of the type-B RRs (IbRR20-IbRR28), while no interaction affinity was detected for IbHP3. Our systematic analyses could provide insights into the characterization of the TCS genes, and further the development of functional studies in sweet potato.

6.
Chromosome Res ; 29(3-4): 285-300, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34152515

RESUMO

Chromosome karyotyping analysis is particularly useful in determining species relationships and the origin of polyploid species. Identification of individual chromosomes is the foundation for karyotype development. For Fragaria (strawberry) species, definitive identification of the individual chromosomes is extremely difficult because of their small size and similar shape. Here, we identified all chromosomes for 11 representative Fragaria species with different ploidy using a set of oligonucleotide-based probes developed in Fragaria vesca. Comprehensive molecular cytogenetic karyotypes were established based on the individually identified chromosomes. In addition, we used oligo probes to assign the 5S and 45S rDNA loci to specific chromosomes in 16 Fragaria species. We found that these Fragaria species maintained a remarkably conserved karyotype. No inter-chromosomal structural rearrangements at the cytological level were observed in any of the chromosomes among these species. Despite karyotypic stability and similarity, variations in the signal intensity of oligo probes were observed among the homologous chromosomes in several polyploid species. Moreover, most Fragaria species also showed differences in the distribution patterns of 45S and 5S rDNA. These data provide new insights into the origins of several polyploid Fragaria species.


Assuntos
Coloração Cromossômica , Fragaria , DNA Ribossômico/genética , Fragaria/genética , Cariótipo , Cariotipagem
7.
Plants (Basel) ; 9(7)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650507

RESUMO

In recent years, the purple-fleshed sweet potato has attracted more attention because of its high nutritional value. The cytogenetics of this crop is relatively unexplored, limiting our knowledge on its genetic diversity. Therefore, we conducted cytogenetic analysis of 76 purple-fleshed sweet potato cultivars to analyze the chromosome structure and distribution of 45S and 5S rDNA. We noted that only 62 cultivars had 90 chromosomes, and the others were aneuploid with 88, 89, 91, or 92 chromosomes. The number of 45S rDNA in the 76 cultivars varied from 16 to 21; these sites showed different signal sizes and intensities and were localized at the chromosomal termini or satellite. The number of 5S rDNA was relatively stable; 74 cultivars showed six sites located at the chromosomal sub-terminal or near the centromere. Only the 'Quanzishu 96' and 'Yuzixiang 10' showed seven and five 5S rDNA sites, respectively. Additionally, both parent cultivars of 'Quanzishu 96' showed 18 45S and six 5S rDNA sites. Overall, our results indicate a moderate diversity in the distribution pattern of rDNAs. Our findings provide comprehensive cytogenetic information for the identification of sweet potato chromosomes, which can be useful for developing a high-quality germplasm resource.

8.
Urol Oncol ; 38(9): 738.e1-738.e8, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32622721

RESUMO

OBJECTIVES: The aberrant expression of long noncoding RNAs (lncRNAs) plays roles in cancer development. In this work, we measured the expression of lncRNA terminal differentiation-induced non-coding RNA (TINCR) in urothelial carcinoma of the bladder (UCB), determined its impact on the proliferation of UCB in vitro and in vivo and identified its possible targets. METHODS: The expression levels of genes were measured by Real-Time quantitative Polymerase Chain Reaction (qPCR). Cell proliferation, cell motility, and cell apoptosis were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, wound healing assay, and ELISA, respectively. Tumor growth in vivo was determined by xenograft formation assay in nude mice. The predicted binding site between TINCR and hsa-miR-125b was confirmed by dual luciferase reporter assay. RESULTS: The expression levels of TINCR were higher in cancerous tissues than that in paired noncancerous tissues of UCB. Higher expression levels of TINCR were positively associated with high-grade, invasive, and recurring tumors. Depletion of TINCR retarded proliferation, decreased motility, increased apoptosis in UCB cells, and markedly reduced tumor growth in xenograft nude mice. The predicted binding site between TINCR and hsa-miR-125b was functional. TINCR downregulated hsa-miR-125b in UCB cells. Hsa-miR-125b mimic reversed the proliferation caused by TINCR up-expression in UCB cells. CONCLUSIONS: Up-regulation of TINCR may act as an unfavorable indicator for the diseasing status of UCB. TINCR facilitates bladder cancer proliferation in vitro and in vivo. Hsa-miR-125b is a target for TINCR in UCB.


Assuntos
Carcinoma de Células de Transição/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Animais , Carcinoma de Células de Transição/patologia , Proliferação de Células , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/genética , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia
9.
J Integr Plant Biol ; 62(12): 1942-1966, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32618097

RESUMO

High salinity is one of the major limiting factors that reduces crop productivity and quality. Herein, we report that small SALT TOLERANCE ENHANCER1 (STE1) protein without any known conserved domains is required for tomato salt tolerance. Overexpression (OE) of SlSTE1 enhanced the tolerance to multiple chloride salts (NaCl, KCl, and LiCl) and oxidative stress, along with elevated antioxidant enzyme activities, increased abscisic acid (ABA) and chlorophyll contents, and reduced malondialdehyde (MDA) and reactive oxygen species (ROS) accumulations compared to that of wild-type (WT) plants. Moreover, decreased K+ efflux and increased H+ efflux were detected in the OE plants, which induced a higher K+ /Na+ ratio. In contrast, SlSTE1-RNAi plants displayed decreased tolerance to salt stress. RNA-seq data revealed 1 330 differentially expressed genes in the OE plants versus WT plants under salt stress, and the transcription of numerous and diverse genes encoding transcription factors, stress-related proteins, secondary metabolisms, kinases, and hormone synthesis/signaling-related proteins (notably ABA and 1-aminocyclopropane-1-carboxylate) was greatly elevated. Furthermore, SlSTE1-OE plants showed increased sensitivity to ABA, and the results suggest that SlSTE1 promotes ABA-dependent salt stress-responsive pathways by interacting with SlPYLs and SlSnRK2s. Collectively, our findings reveal that the small SlSTE1 protein confers salt tolerance via ABA signaling and ROS scavenging and improves ion homeostasis in tomato.


Assuntos
Ácido Abscísico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Solanum lycopersicum/metabolismo , Secas , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
10.
Front Plant Sci ; 11: 687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528515

RESUMO

Sweetpotato (Ipomoea batatas (L.) Lam.) is an important industrial and food crop. Both chilling and heat stress inhibits sweetpotato growth and development and then affects yield. However, the physiological and molecular mechanisms of sweetpotato response to chilling and heat stress is unclear. In this study, we investigated the effect of extreme temperature on sweetpotato physiological response, with a focus on oxidative stress and the potential microRNA (miRNA)-mediated molecular mechanism. Our results showed that both chilling and heat stress resulted in accumulation of reactive oxygen species (ROS), including H2O2 and O2 -, and caused oxidative stress in sweetpotato. This further affected the activities of oxidative stress-related enzymes and products, including SOD, POD, and MDA. Both chilling and heat stress inhibited POD activities but induced the enzyme activities of SOD and MDA. This suggests that sweetpotato cells initiated its own defense mechanism to handle extreme temperature-caused oxidative damage. Oxidative damage and repair are one mechanism that sweetpotato plants respond to extreme temperatures. Another potential mechanism is miRNA-mediated gene response. Chilling and heat stress altered the expression of stress-responsive miRNAs in sweetpotato seedlings. These miRNAs regulate sweetpotato response to extreme stress through targeting individual protein-coding genes.

11.
J Agric Food Chem ; 68(29): 7591-7600, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32585101

RESUMO

Black rot, caused by Ceratocystis fimbriata, is a destructive disease of sweet potatoes (Ipomoea batatas). In this study, a novel chitinase (IbChiA) was screened from sweet potatoes, which showed a remarkably higher expression level in resistant varieties than in susceptible ones after inoculation with C. fimbriata. Sequence analysis indicated that IbChiA belongs to family 19 class II extracellular chitinase with a MW of 26.3 kDa and pI of 5.96. Recombinant IbChiA, produced by Pichia pastoris, displayed antifungal activity and stability. IbChiA could restrain the mycelium extension of C. fimbriata. FDA/PI double staining combined with transmission electron microscopy observation revealed the remarkable fungicidal effect of IbChiA on the conidia of C. fimbriata. The disease symptoms on the surface of slices and tuberous roots of sweet potatoes were significantly reduced after treatment with IbChiA. These results indicated that IbChiA could be used as a potential biofungicide to replace chemical fungicides.


Assuntos
Quitinases/imunologia , Ipomoea batatas/enzimologia , Ipomoea batatas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/imunologia , Sequência de Aminoácidos , Ceratocystis/crescimento & desenvolvimento , Ceratocystis/fisiologia , Quitinases/química , Quitinases/genética , Ipomoea batatas/química , Doenças das Plantas/imunologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Alinhamento de Sequência
12.
Theor Appl Genet ; 133(7): 2271-2290, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32306094

RESUMO

The legendary cucumber inbred line WI2757 possesses a rare combination of resistances against nine pathogens, which is an important germplasm for cucumber breeding. However, WI2757 flowers late and does not perform well under field conditions. The genetic basis for horticulturally important traits other than disease resistances in WI2757 is largely unknown. In this study, we conducted QTL mapping using F2 and recombinant inbred line (RIL) populations from the WI2757 × True Lemon cross that were segregating for multiple traits. Phenotypic data were collected in replicated field trials across multiple years for seven traits including fruit carpel number (CN) and sex expression. A high-density SNP-based genetic map was developed with genotyping by sequencing of the RIL population, which revealed a region on chromosome 1 with strong recombination suppression. The reduced recombination in this region was due to a ~ 10-Mbp paracentric inversion in WI2757 that was confirmed with additional segregation and cytological (FISH) analyses. Thirty-six QTL were detected for flowering time, fruit length (FL), fruit diameter (FD), fruit shape (LD), fruit number (FN), CN, and powdery mildew resistance. Five moderate- or major-effect QTL for FL, FD, LD, and FN inside the inversion are likely the pleiotropic effects of the andromonoecy (m), or the cn locus. The major-effect flowering time QTL ft1.1 was also mapped inside the inversion, which seems to be different from the previously assigned delayed flowering in WI2757. Implications of these findings on the use of WI2757 in cucumber breeding are discussed.


Assuntos
Cucumis sativus/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Mapeamento Cromossômico , Cruzamentos Genéticos , Flores , Genes de Plantas , Ligação Genética , Genótipo , Hibridização in Situ Fluorescente , Desequilíbrio de Ligação , Repetições de Microssatélites , Fenótipo , Doenças das Plantas/microbiologia
13.
Hortic Res ; 7: 32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194968

RESUMO

Cucumber, Cucumis sativus is an important vegetable crop, and gynoecy has played a critical role in yield increase of hybrid cucumber production. Cucumber has a unique genetic system for gynoecious sex expression, which is determined by the copy number variation (CNV)-based, dominant, and dosage-dependent femaleness (F) locus. However, this gynoecy expression system seems unstable since monecious plants could often be found in F-dependent gynoecious cucumber inbreds. We hypothesized that gynoecy instability (gynoecy loss) may be due to unequal crossing over (UCO) during meiosis among repeat units of the CNV. In this study, using high throughput genome resequencing, fiber-FISH and genomic qPCR analyses, we first confirmed and refined the structure of the F locus, which was a CNV of a 30.2-kb tandem repeat. Gynoecious plants contained three genes: CsACS1, CsACS1G, and CsMYB, of which CsACS1G is a duplication of CsACS1 but with a recombinant distal promoter that may contribute to gynoecy sex expression. In two large populations from self-pollinated gynoecious inbred lines, 'gynoecy loss' mutants were identified with similar mutation rates (~0.12%). We show that these monecious mutants have lost CsACS1G. In addition, we identified gynoecious lines in natural populations that carry two copies of CSACS1G. We proposed a model to explain gynoecy instability in F-dependent cucumbers, which is caused by UCO among CSACS1/G units during meiosis. The findings present a convincing case that the phenotypic variation of an economically important trait is associated with the dynamic changes of copy numbers at the F locus. This work also has important implications in cucumber breeding.

14.
BMC Plant Biol ; 19(1): 184, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060496

RESUMO

BACKGROUND: Since their discovery, vacuolar processing enzymes (VPEs) have consistently been investigated as programmed cell death (PCD) initiators and participants in plant development and responses to biotic or abiotic stresses, in part due to similarities with the apoptosis regulator caspase-1. However, recent studies show additional functions of VPE in tomatoes, specifically in sucrose accumulation and fruit ripening. RESULTS: Herein, we evaluated the functions of VPE from sweetpotato, initially in expression pattern analyses of IbVPE1 during development and senescence. Subsequently, we identified physiological functions by overexpressing IbVPE1 in Arabidopsis thaliana, and showed reduced leaf sizes and numbers and early flowering, and elucidated the underlying molecular mechanisms. CONCLUSIONS: The present data demonstrate functions of the VPE gene family in development and senescence and in regulation of flowering times, leaf sizes and numbers, and senescence phenotypes in Arabidopsis thaliana.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Clorofila/metabolismo , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Escuridão , Especificidade de Órgãos/genética , Fenótipo , Complexo de Proteína do Fotossistema II/metabolismo , Filogenia , Folhas de Planta/anatomia & histologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Fatores de Transcrição/metabolismo
15.
PeerJ ; 7: e6563, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881765

RESUMO

BACKGROUND: Ipomoea is the largest genus in the family Convolvulaceae. The species in this genus have been widely used in many fields, such as agriculture, nutrition, and medicine. With the development of next-generation sequencing, more than 50 chloroplast genomes of Ipomoea species have been sequenced. However, the repeats and divergence regions in Ipomoea have not been well investigated. In the present study, we sequenced and assembled eight chloroplast genomes from sweet potato's close wild relatives. By combining these with 32 published chloroplast genomes, we conducted a detailed comparative analysis of a broad range of Ipomoea species. METHODS: Eight chloroplast genomes were assembled using short DNA sequences generated by next-generation sequencing technology. By combining these chloroplast genomes with 32 other published Ipomoea chloroplast genomes downloaded from GenBank and the Oxford Research Archive, we conducted a comparative analysis of the repeat sequences and divergence regions across the Ipomoea genus. In addition, separate analyses of the Batatas group and Quamoclit group were also performed. RESULTS: The eight newly sequenced chloroplast genomes ranged from 161,225 to 161,721 bp in length and displayed the typical circular quadripartite structure, consisting of a pair of inverted repeat (IR) regions (30,798-30,910 bp each) separated by a large single copy (LSC) region (87,575-88,004 bp) and a small single copy (SSC) region (12,018-12,051 bp). The average guanine-cytosine (GC) content was approximately 40.5% in the IR region, 36.1% in the LSC region, 32.2% in the SSC regions, and 37.5% in complete sequence for all the generated plastomes. The eight chloroplast genome sequences from this study included 80 protein-coding genes, four rRNAs (rrn23, rrn16, rrn5, and rrn4.5), and 37 tRNAs. The boundaries of single copy regions and IR regions were highly conserved in the eight chloroplast genomes. In Ipomoea, 57-89 pairs of repetitive sequences and 39-64 simple sequence repeats were found. By conducting a sliding window analysis, we found six relatively high variable regions (ndhA intron, ndhH-ndhF, ndhF-rpl32, rpl32-trnL, rps16-trnQ, and ndhF) in the Ipomoea genus, eight (trnG, rpl32-trnL, ndhA intron, ndhF-rpl32, ndhH-ndhF, ccsA-ndhD, trnG-trnR, and pasA-ycf3) in the Batatas group, and eight (ndhA intron, petN-psbM, rpl32-trnL, trnG-trnR, trnK-rps16, ndhC-trnV, rps16-trnQ, and trnG) in the Quamoclit group. Our maximum-likelihood tree based on whole chloroplast genomes confirmed the phylogenetic topology reported in previous studies. CONCLUSIONS: The chloroplast genome sequence and structure were highly conserved in the eight newly-sequenced Ipomoea species. Our comparative analysis included a broad range of Ipomoea chloroplast genomes, providing valuable information for Ipomoea species identification and enhancing the understanding of Ipomoea genetic resources.

16.
Genome ; 62(4): 243-252, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30785785

RESUMO

Sweet potato is one of the most important crops worldwide; however, basic research in this crop is limited. In this study, we aimed to construct a detailed karyotype of six species of Ipomoea (hexaploid Ipomoea batatas and five related species, namely, one tetraploid, I. tabascana and four diploids, I. splendor-sylvae, I. trifida, I. tenuissima, and I. × leucantha) and understand the relationship among these species. Two satellite repeats (viz., Itf_1 and Itf_2) were identified from the diploid I. trifida genome sequence using RepeatExplorer on Galaxy. Together with the ribosomal DNA (rDNA), although without distinguishable chromosomes, a detailed karyotype was constructed for the six species. Our results showed a similar karyotype between I. tenuissima and I. × leucantha, indicating their close relationship. The signal distribution pattern of Itf_1, 45S rDNA combination, detected only in I. trifida, I. tabascana, and I. batatas, implied their close relationships. The chromosomes carrying 5S rDNA could be conserved among the six species as they always carried the Itf_2 signals, which generated a similar signal distribution pattern. The results enabled a detailed comparative cytogenetic analysis, providing valuable information to understand the relationship among these species and help assemble the genome sequence of the six species of Ipomoea.


Assuntos
DNA de Plantas , Ipomoea/genética , Cariótipo , Sequências Repetitivas de Ácido Nucleico , Cromossomos de Plantas , DNA Ribossômico , Ipomoea batatas/genética , Ploidias , Análise de Sequência de DNA
17.
Genomics ; 111(5): 1006-1017, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29792923

RESUMO

Sweetpotato (Ipomoea batatas L.) is a globally important economic food crop. It belongs to Convolvulaceae family and origins in the tropics; however, sweetpotato is sensitive to cold stress during storage. In this study, we performed transcriptome sequencing to investigate the sweetpotato response to chilling stress during storage. A total of 110,110 unigenes were generated via high-throughput sequencing. Differentially expressed genes (DEGs) analysis showed that 18,681 genes were up-regulated and 21,983 genes were down-regulated in low temperature condition. Many DEGs were related to the cell membrane system, antioxidant enzymes, carbohydrate metabolism, and hormone metabolism, which are potentially associated with sweetpotato resistance to low temperature. The existence of DEGs suggests a molecular basis for the biochemical and physiological consequences of sweetpotato in low temperature storage conditions. Our analysis will provide a new target for enhancement of sweetpotato cold stress tolerance in postharvest storage through genetic manipulation.


Assuntos
Resposta ao Choque Frio , Genes de Plantas , Ipomoea batatas/genética , Regulação da Expressão Gênica de Plantas , Transcriptoma
18.
BMC Plant Biol ; 18(1): 240, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333010

RESUMO

BACKGROUND: Arachis contains 80 species that carry many beneficial genes that can be utilized in the genetic improvement of peanut (Arachis hypogaea L. 2n = 4x = 40, genome AABB). Chromosome engineering is a powerful technique by which these genes can be transferred and utilized in cultivated peanut. However, their small chromosomes and insufficient cytological markers have made chromosome identification and studies relating to genome evolution quite difficult. The development of efficient cytological markers or probes is very necessary for both chromosome engineering and genome discrimination in cultivated peanut. RESULTS: A simple and efficient oligonucleotide multiplex probe to distinguish genomes, chromosomes, and chromosomal aberrations of peanut was developed based on eight single-stranded oligonucleotides (SSONs) derived from repetitive sequences. High-resolution karyotypes of 16 Arachis species, two interspecific F1 hybrids, and one radiation-induced M1 plant were then developed by fluorescence in situ hybridization (FISH) using oligonucleotide multiplex, 45S and 5S rDNAs, and genomic in situ hybridization (GISH) using total genomic DNA of A. duranensis (2n = 2x = 20, AA) and A. ipaënsis (2n = 2x = 20, BB) as probes. Genomes, chromosomes, and aberrations were clearly identifiable in the established karyotypes. All eight cultivars had similar karyotypes, whereas the eight wild species exhibited various chromosomal variations. In addition, a chromosome-specific SSON library was developed based on the single-copy sequence of chromosome 6A of A. duranensis. In combination with repetitive SSONs and rDNA FISH, the single-copy SSON library was applied to identify the corresponding A3 chromosome in the A. duranensis karyotype. CONCLUSIONS: The development of repetitive and single-copy SSON probes for FISH and GISH provides useful tools for the differentiation of chromosomes and identification of structural chromosomal rearrangement. It facilitates the development of high-resolution karyotypes and detection of chromosomal variations in Arachis species. To our knowledge, the methodology presented in this study demonstrates for the first time the correlation between a sequenced chromosome region and a cytologically identified chromosome in peanut.


Assuntos
Arachis/genética , Cromossomos de Plantas/genética , Rearranjo Gênico , Genoma de Planta/genética , Coloração Cromossômica , DNA Ribossômico , Hibridização in Situ Fluorescente , Cariotipagem , Sondas Moleculares , Oligonucleotídeos , Sequências Repetitivas de Ácido Nucleico/genética
19.
Dalton Trans ; 47(38): 13608-13615, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30207359

RESUMO

Coupled adsorption and photocatalytic oxidation brings high expectations regarding the fast and efficient removal of gaseous pollutants in air. However, to fabricate an adsorbent-photocatalyst composite, coating of a photocatalyst on adsorbent support inevitably results in loss of adsorption and light blocking on interior surfaces. In this work, we attempt to develop an adsorbent-photocatalyst monolith composite, which not only perfectly retains original high adsorption capacity, but also allows complete penetration of UV light through the whole monolith. We employ a SiO2 aerogel monolith with a diameter of 2.5 cm and thickness of 0.7 cm as adsorbent and support. After atomic layer deposition (ALD) followed by calcination, 0.32-1.25 wt% TiO2 is dispersed on the skeleton of the SiO2 aerogel. In spite of such a low level of loading, the monolith composites exhibit fast and efficient removal of gaseous acetaldehyde and NO. Therein, the best performance is achieved at a loading of 0.6 wt% TiO2. By dark adsorption, the acetaldehyde pollutant with initial concentration of 200 ppm can be adsorbed by 54% within 10 min. Moreover, the light transmittance at 387 nm can be retained as high as 6% after penetrating through the whole monolith, confirming that all loaded TiO2 nanoparticles can participate in the photocatalytic oxidation of acetaldehyde. Under UV irradiation with intensity close to natural sunlight, the preadsorbed acetaldehyde can be completely mineralized into CO2 by photocatalytic oxidation in another 60 min, benefiting from the ultradispersion of TiO2 nanoparticles inside the SiO2 aerogel. The study provides a novel three-dimensional model of an adsorbent-photocatalyst composite for the fast and efficient removal of gaseous pollutants.

20.
BMC Psychiatry ; 18(1): 226, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005610

RESUMO

BACKGROUND: Widespread cortical gray matter alternations in people with schizophrenia are correlated with both psychotic symptoms and cognitive/behavioral abnormalities, including the impairments of exploratory eye movement (EEM). Particularly, the loss of gray matter density is specifically related to deficits of the responsive search score (RSS) of EEM in schizophrenia. It is unknown, however, whether the schizophrenia-related RSS deficits are associated with certain psychotic symptoms, such as hallucinations. METHODS: In 33 participants with schizophrenia, the measurement of EEM, assessment of the hallucination severity using Positive and Negative Syndrome Scale (PANSS) and a voxel-based morphometric analysis of cortical gray matter volume (GMV) were conducted to investigate the relationships between the RSS of EEM, symptom severity, and GMV. In 29 matched healthy controls, the measurement of EEM and a voxel-based morphometric analysis of cortical GMV were also conducted to investigate the relationship between the RSS of EEM and GMV. RESULTS: In participants with schizophrenia, the hallucination severity was significantly negatively correlated with both the RSS and the GMV of a large number of brain regions in the frontal, temporal, parietal, orbitofrontal, calcarine, cingulate, and insular cortices, and rolandic operculum, hippocampus, parahippocampal gyrus, and thalamus. Also in participants with schizophrenia, the RSS was significantly positively correlated with the GMV in the left supplementary motor area (SMA), left superior frontal cortex (SFG), bilateral precentral gyri, bilateral postcentral gyri, and bilateral middle frontal cortices. More importantly, the GMV of the SMA, SFG, and precentral gyrus in the left hemisphere was not only significantly negatively correlated with the hallucination severity but also significantly positively correlated with the RSS. No significant correlation could be revealed between the RSS and the GMV of any brain regions in healthy controls. CONCLUSIONS: There was a significantly negative association between the hallucination severity and the RSS of EEM, suggesting that the RSS may be a potential biomarker for predicting the hallucination severity of schizophrenia. Also, the GMV of the left SMA, SFG, and precentral gyrus may be the common substrates underlying both hallucination induction and the RSS in people with schizophrenia.


Assuntos
Encéfalo/diagnóstico por imagem , Movimentos Oculares , Substância Cinzenta , Alucinações , Esquizofrenia , Adulto , Estudos de Casos e Controles , Correlação de Dados , Medições dos Movimentos Oculares , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Alucinações/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Índice de Gravidade de Doença
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