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1.
J Obstet Gynaecol Res ; 48(2): 385-392, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34866285

RESUMO

AIM: This study aimed to clarify the feasibility of a mobile cardiotocogram (CTG) device for self-monitoring fetal heart rate (FHR) in low-risk singleton pregnant women. METHODS: This study was conducted at six university hospitals and seven maternity clinics in Japan. Using a mobile cardiotocogram device (iCTG, Melody International Ltd., Kagawa, Japan), participants of more than 34 gestational weeks measured the FHR by themselves at least once a week until hospitalization for delivery. We evaluated the acquisition rate of evaluable FHR recordings and the frequency of abnormal FHR patterns according to the CTG classification system of the Japan Society of Obstetrics and Gynecology (JSOG). The participants also underwent a questionnaire survey after delivery to evaluate their satisfaction level of self-monitoring FHR using the mobile CTG device. RESULTS: A total of 1278 FHR recordings from 101 women were analyzed. Among them, 1276 (99.8%) were readable for more than 10 min continuously, and the median percentage of the total readable period in each recording was 98.9% (range, 51.4-100). According to the JSOG classification system, 1245 (97.6%), 9 (0.7%), 18 (1.4%), and four (0.3%) FHR patterns were classified as levels 1, 2, 3, and 4, respectively. The questionnaire survey revealed high participant satisfaction with FHR self-monitoring using the iCTG. CONCLUSION: The mobile CTG device is a feasible tool for self-monitoring FHR, with a high participant satisfaction level.


Assuntos
Cardiotocografia , Frequência Cardíaca Fetal , Estudos de Viabilidade , Feminino , Monitorização Fetal , Humanos , Japão , Gravidez , Gestantes
2.
Proc Natl Acad Sci U S A ; 110(42): 17137-42, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24082137

RESUMO

Photoperiodic floral induction has had a significant impact on the agricultural and horticultural industries. Changes in day length are perceived in leaves, which synthesize systemic flowering inducers (florigens) and inhibitors (antiflorigens) that determine floral initiation at the shoot apex. Recently, FLOWERING LOCUS T (FT) was found to be a florigen; however, the identity of the corresponding antiflorigen remains to be elucidated. Here, we report the identification of an antiflorigen gene, Anti-florigenic FT/TFL1 family protein (AFT), from a wild chrysanthemum (Chrysanthemum seticuspe) whose expression is mainly induced in leaves under noninductive conditions. Gain- and loss-of-function analyses demonstrated that CsAFT acts systemically to inhibit flowering and plays a predominant role in the obligate photoperiodic response. A transient gene expression assay indicated that CsAFT inhibits flowering by directly antagonizing the flower-inductive activity of CsFTL3, a C. seticuspe ortholog of FT, through interaction with CsFDL1, a basic leucine zipper (bZIP) transcription factor FD homolog of Arabidopsis. Induction of CsAFT was triggered by the coincidence of phytochrome signals with the photosensitive phase set by the dusk signal; flowering occurred only when night length exceeded the photosensitive phase for CsAFT induction. Thus, the gated antiflorigen production system, a phytochrome-mediated response to light, determines obligate photoperiodic flowering response in chrysanthemums, which enables their year-round commercial production by artificial lighting.


Assuntos
Chrysanthemum/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Fotoperíodo , Proteínas de Plantas/biossíntese , Transativadores/biossíntese , Sequência de Aminoácidos , Chrysanthemum/genética , Flores/genética , Loci Gênicos/fisiologia , Dados de Sequência Molecular , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Homologia de Sequência de Aminoácidos , Transativadores/genética
3.
J Exp Bot ; 64(4): 909-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23314814

RESUMO

Flowering time of the short-day plant Chrysanthemum morifolium is largely dependent upon daylength, but it is also distinctly influenced by other environmental factors. Flowering is delayed by summer heat. Here, the underlying basis for this phenomenon was investigated. Heat-induced flowering retardation occurred similarly in C. morifolium and C. seticuspe, a wild-type diploid chrysanthemum. In both plants, this flowering retardation occurred mainly because of inhibition of capitulum development. Concurrently, expression of flowering-related genes in the shoot tip was delayed under high temperature conditions. In chrysanthemums, FLOWERING LOCUS T-like 3 (FTL3) has been identified as a floral inducer produced in the leaves after short-day stimuli and transported to the shoot tip. In C. seticuspe, heat-induced flowering retardation was accompanied by a reduction in FTL3 expression in the leaves. Two C. morifolium cultivars with flowering times that are differently affected by growth temperature were also examined. High temperature-induced FTL3 repression was observed in the leaves of both cultivars, although the degree of repression was greater in the heat-sensitive cultivar than in the heat-tolerant cultivar. When a scion of the heat-sensitive cultivar was grafted onto the stock of the heat-tolerant cultivar, flowering in the shoot tip was less sensitive to heat. Conversely, a scion of the heat-tolerant cultivar grafted onto the heat-sensitive cultivar showed increased heat sensitivity. Thus, several lines of evidence suggest that the reduction of FTL3 signalling from the leaves to the shoot tip at high temperatures is involved in flowering retardation in chrysanthemums.


Assuntos
Chrysanthemum/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Temperatura Alta , Chrysanthemum/crescimento & desenvolvimento , Flores/genética , Fotoperíodo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Transporte Proteico , RNA de Plantas/genética , RNA de Plantas/metabolismo , Transdução de Sinais , Especificidade da Espécie , Fatores de Tempo
4.
Hortic Res ; 9: uhac170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324641

RESUMO

White rust caused by Puccinia horiana is one of the most serious diseases of chrysanthemum (Chrysanthemum × morifolium). In this study, we report the DNA markers associated with resistance against P. horiana via a simple approach using the genome of a wild diploid relative, Chrysanthemum seticuspe. First, we identified the important region of the genome in the resistant cultivar "Ariesu" via a genome-wide association study. Simplex single nucleotide polymorphism (SNP) markers mined from ddRAD-Seq were used in a biparental population originating from crosses between resistant "Ariesu" and susceptible "Yellow Queen". The C. seticuspe genome was used as a reference. For the fine mapping of P. horiana resistance locus 2 (Phr2), a comparative whole genome sequencing study was conducted. Although the genome sequences of chrysanthemum cultivars assembled via the short-read approach were fragmented, reliable genome alignments were reconstructed by mapping onto the chromosome level of the C. seticuspe pseudomolecule. Base variants were then identified by comparing the assembled genome sequences of resistant "Ariesu" and susceptible "Yellow Queen". Consequently, SNP markers that were closer to Phr2 compared with ddRAD-Seq markers were obtained. These SNP markers co-segregated with resistance in F1 progenies originating from resistant "Ariesu" and showed robust transferability for detecting Phr2-conferring resistance among chrysanthemum genetic resources. The wild C. seticuspe pseudomolecule, a de facto monoploid genome used for ddRAD-Seq analysis and assembled genome sequence comparison, demonstrated this method's utility as a model for developing DNA markers in hexaploid chrysanthemum cultivars.

5.
Physiol Plant ; 141(4): 383-93, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21241311

RESUMO

A rosette plant of Eustoma grandiflorum requires vernalization (exposure to a period of cold temperature) and long-day conditions to promote flowering, while prolonged cold or cool temperatures in post-vernalization periods delay flowering. This study aimed to investigate the effect of growth conditions on flowering regulation in Eustoma. In Arabidopsis, vernalization suppresses a floral repressor gene, FLOWERING LOCUS C (FLC) and upregulates floral promoter genes, such as SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and FLOWERING LOCUS T (FT). We identified and characterized the Eustoma homologs of these genes. In contrast to Arabidopsis FLC, Eustoma grandiflorum FLC-like (EgFLCL) expression was upregulated by cold temperature and downregulated by subsequent warm temperature exposure. The expression of Eustoma grandiflorum SOC1-like (EgSOC1L) and FT-like (EgFTL) genes was not significantly induced during vernalization, but their transcripts increased during a warm post-vernalization period in the long days. Vernalized plants grown under cool post-vernalization temperatures exhibited higher EgFLCL expression, lower EgSOC1L and EgFTL expression and flowered later than those grown under warm temperatures. Overexpression of EgFLCL cDNA repressed flowering in transgenic Arabidopsis, whereas overexpression of EgSOC1L or EgFTL cDNA promoted flowering. Our results suggest that flowering regulation by vernalization in Eustoma differs from the paradigm developed for Arabidopsis. EgFLCL is regulated by temperature and may be involved in floral repression during cold and cool seasons. Warm- and long-day conditions following vernalization are required to induce two putative floral promoters, EgSOC1L and EgFTL, effectively.


Assuntos
Proteínas de Arabidopsis/química , Temperatura Baixa , Flores/genética , Regulação da Expressão Gênica de Plantas , Gentianaceae/genética , Proteínas de Plantas/genética , Homologia de Sequência de Aminoácidos , Arabidopsis/genética , DNA Complementar/genética , Flores/fisiologia , Genoma de Planta/genética , Gentianaceae/crescimento & desenvolvimento , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Filogenia , Folhas de Planta/fisiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
6.
Sci Technol Adv Mater ; 11(2): 025002, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27877330

RESUMO

Anodic porous alumina with duplex layers exhibits a voltage-induced switching effect and is a promising candidate for resistive random access memory. The nanostructural analysis of porous alumina is important for understanding the switching effect. We investigated the difference between the two layers of an anodic porous alumina film using transmission electron microscopy and electron energy-loss spectroscopy. Diffraction patterns showed that both layers are amorphous, and the electron energy-loss spectroscopy indicated that the inner layer contains less oxygen than the outer layer. We speculate that the conduction paths are mostly located in the oxygen-depleted area.

7.
Plant Sci ; 283: 247-255, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31128695

RESUMO

Chrysanthemums require continuous short-days (SD) for anthesis. FTL3 (FLOWERING LOCUS T-like 3), a floral promoter expressed in chrysanthemum leaf, forms a complex with its interacting partner FDL1 to induce floral meristem identity gene AFL1. We explored the FTL3 induction mechanism during SD repeats in Chrysanthemum seticuspe. CsFTL3 expression was not immediately induced by a shift from long-day (LD) to SD, but gradually increased until the capitulum development stage under repeated SDs. Overexpression of CsFTL3 transgene increased endogenous leaf CsFTL3 induction under SD but not LD. Overexpression of CsFDL1 promoted anthesis and increased CsAFL1 and CsFTL3 expression under SD. Loss-of-function of CsFDL1 by RNAi resulted in delayed anthesis and downregulation of leaf CsAFL1 and CsFTL3, indicating the necessity of CsFDL1 for CsFTL3 induction. Overexpression of an antagonistic protein of CsFTL3 or CsFDL1 inhibited leaf CsFTL3 induction. CsFTL3 expression was positively regulated during SDs by a feedback mechanism involving the CsFTL3-CsFDL1 complex. Furthermore, flowering was accomplished by feedback with high levels of CsFTL3 induction under repeated SDs.


Assuntos
Chrysanthemum/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Proteínas de Plantas/fisiologia , Chrysanthemum/metabolismo , Chrysanthemum/fisiologia , Retroalimentação Fisiológica , Flores/metabolismo , Flores/fisiologia , Técnicas de Silenciamento de Genes , Fotoperíodo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Regiões Promotoras Genéticas/fisiologia , Transcriptoma
8.
Sci Rep ; 9(1): 13947, 2019 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558738

RESUMO

The use of DNA markers has revolutionized selection in crop breeding by linkage mapping and QTL analysis, but major problems still remain for polyploid species where marker-assisted selection lags behind the situation in diploids because of its high genome complexity. To overcome the complex genetic mode in the polyploids, we investigated the development of a strategy of genome-wide association study (GWAS) using single-dose SNPs, which simplify the segregation patterns associated polyploids, with respect to the development of DNA markers. In addition, we employed biparental populations for the GWAS, wherein the SNP allele frequency could be predicted. The research investigated whether the method could be used to effectively develop DNA markers for petal color in autohexaploid chrysanthemum (Chrysanthemum morifolium; 2n = 6x = 54). The causal gene for this trait is already-known CmCCD4a encoding a dioxygenase which cleaves carotenoids in petals. We selected 9,219 single-dose SNPs, out of total 52,489 SNPs identified by dd-RAD-Seq, showing simplex (1 × 0) and double-simplex (1 × 1) inheritance pattern according to alternative allele frequency with respect to the SNP loci in the F1 population. GWAS, using these single-dose SNPs, discovered highly reproducible SNP markers tightly linked to the causal genes. This is the first report of a straightforward GWAS-based marker developing system for use in autohexaploid species.


Assuntos
Chrysanthemum/genética , Flores/genética , Polimorfismo de Nucleotídeo Único , Poliploidia , Carotenoides/metabolismo , Flores/metabolismo , Genoma de Planta , Estudo de Associação Genômica Ampla/métodos , Pigmentação/genética
9.
DNA Res ; 26(3): 195-203, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689773

RESUMO

Cultivated chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the most economically important ornamental crops grown worldwide. It has a complex hexaploid genome (2n = 6x = 54) and large genome size. The diploid Chrysanthemum seticuspe is often used as a model of cultivated chrysanthemum, since the two species are closely related. To expand our knowledge of the cultivated chrysanthemum, we here performed de novo whole-genome assembly in C. seticuspe using the Illumina sequencing platform. XMRS10, a C. seticuspe accession developed by five generations of self-crossing from a self-compatible strain, AEV2, was used for genome sequencing. The 2.72 Gb of assembled sequences (CSE_r1.0), consisting of 354,212 scaffolds, covered 89.0% of the 3.06 Gb C. seticuspe genome estimated by k-mer analysis. The N50 length of scaffolds was 44,741 bp. For protein-encoding genes, 71,057 annotated genes were deduced (CSE_r1.1_cds). Next, based on the assembled genome sequences, we performed linkage map construction, gene discovery and comparative analyses for C. seticuspe and cultivated chrysanthemum. The generated C. seticuspe linkage map revealed skewed regions in segregation on the AEV2 genome. In gene discovery analysis, candidate flowering-related genes were newly found in CSE_r1.1_cds. Moreover, single nucleotide polymorphism identification and annotation on the C. × morifolium genome showed that the C. seticuspe genome was applicable to genetic analysis in cultivated chrysanthemums. The genome sequences assembled herein are expected to contribute to future chrysanthemum studies. In addition, our approach demonstrated the usefulness of short-read genome assembly and the importance of choosing an appropriate next genome sequencing technology based on the purpose of the post-genome analysis.


Assuntos
Chrysanthemum/genética , Ligação Genética , Genoma de Planta , Polimorfismo Genético , Sequenciamento Completo do Genoma , Mapeamento Cromossômico , Anotação de Sequência Molecular , Filogenia
10.
Plant Sci ; 287: 110174, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481216

RESUMO

Asteraceae is the largest family of angiosperms, comprising approximately 24,000 species. Molecular genetic studies of Asteraceae are essential for understanding plant diversity. Chrysanthemum morifolium is the most industrially important ornamental species in Asteraceae. Most cultivars of C. morifolium are autohexaploid and self-incompatible. These properties are major obstacles to the genetic analysis and modern breeding of C. morifolium. Furthermore, high genome heterogeneity complicates molecular biological analyses. In this study, we developed a model strain in the genus Chrysanthemum. C. seticuspe is a diploid species with a similar flowering property and morphology to C. morifolium and can be subjected to Agrobacterium-mediated transformation. We isolated a natural self-compatible mutant of C. seticuspe and established a pure line through repeated selfing and selection. The resultant strain, named Gojo-0, was favorable for genetic analyses, including isolation of natural and induced mutants, and facilitated molecular biological analysis, including whole genome sequencing, owing to the simplicity and homogeneity of its genome. Interspecific hybridization with Chrysanthemum species was possible, enabling molecular genetic analysis of natural interspecific variations. The accumulation of research results and resources using Gojo-0 as a platform is expected to promote molecular genetic studies on the genus Chrysanthemum and the genetic improvement of chrysanthemum cultivars.


Assuntos
Chrysanthemum/genética , Chrysanthemum/ultraestrutura , DNA de Plantas/genética , Diploide , Flores/ultraestrutura , Hibridização Genética , Microscopia Eletrônica de Varredura , Modelos Biológicos , Mutação , Filogenia , Melhoramento Vegetal/métodos , Polinização , Autofertilização
11.
J Plant Physiol ; 177: 60-66, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25666540

RESUMO

Flowering time control is important for fruit production in Fragaria × ananassa. The flowering inhibition pathway has been extensively elucidated in the woodland strawberry, Fragaria vesca, whereas the factors involved in its promotion remain unclear. In this study, we investigated the environmental responses of F. × ananassa FT and TFL1-like genes, which are considered key floral promoters and repressors in many plants, respectively. A putative floral promoter, FaFT3, was up-regulated in the shoot tip under short-day and/or low growth temperature, in accordance with the result that these treatments promoted flowering. FaFT3 mRNA accumulated before induction of a floral meristem identity gene, FaAP1. FaFT2, a counterpart of FvFT2, expressed in the flower bud of F. vesca, was not induced in the shoot tip differentiating sepal or stamen, suggesting that this gene works at a later stage than stamen formation. In F. vesca, FvFT1 transmits the long-day signal perceived in the leaves to the shoot tip, and induces the potent floral inhibitor FvTFL1. FaFT1 was expressed in the leaves under long-day conditions in F. × ananassa. Expression of FaTFL1 was higher in the shoot tip under long-day than short-day conditions. Independent of day-length, FaTFL1 expression was higher under high temperature than low temperature conditions. These results suggest that FaFT3 induction by short-day or low temperature stimuli is a key step for flowering initiation. As in F. vesca, F. × ananassa floral inhibition pathways depend on FaTFL1 regulation by day-length via FaFT1, and by temperature.


Assuntos
Flores/crescimento & desenvolvimento , Fragaria/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Sequência de Aminoácidos , Flores/metabolismo , Fragaria/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
12.
Biosci Biotechnol Biochem ; 70(7): 1790-3, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16861818

RESUMO

Previously we reported the purification of soluble gamma-glutamyltransferases (GGTs) from radish cotyledon. Subcellular fractionation of radish cells revealed that soluble GGT is a vacuolar enzyme. Acivicin, a GGT inhibitor, mediated the in vivo catabolism inhibition of the glutathione S-conjugate generated from endogenous glutathione and exogenously supplied monochlorobimane. Thus soluble GGT is possibly involved in the catabolism of glutathione S-conjugates.


Assuntos
Raphanus/enzimologia , gama-Glutamiltransferase/fisiologia , Glutationa/metabolismo , Isoxazóis/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Pirazóis/metabolismo , Vacúolos/enzimologia , gama-Glutamiltransferase/antagonistas & inibidores
13.
Biosci Biotechnol Biochem ; 70(2): 369-76, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16495652

RESUMO

Soluble and cell wall bound gamma-glutamyltransferases (GGTs) were purified from radish (Raphanus sativus L.) cotyledons. Soluble GGTs (GGT I and II) had the same M(r) of 63,000, and were composed of a heavy subunit (M(r), 42,000) and a light one (M(r), 21,000). The properties of GGT I and II were similar. Bound GGTs (GGT A and B) were purified to homogeneity from the pellet after the extraction of soluble GGTs. GGT A and B were monomeric proteins with an M(r) of 61,000. The properties of GGT A and B were similar. Thus, bound GGTs were distinguished from soluble GGTs. The optimal pHs of soluble and bound GGTs were about 7.5. Both soluble and bound GGTs utilized glutathione, gamma-L-glutamyl-p-nitroanilide, oxidized glutathione and the conjugate of glutathione with monobromobimane as substrates, and were inhibited by acivicin, but soluble GGTs were also distinguished from bound GGTs with regard to these properties.


Assuntos
Raphanus/enzimologia , gama-Glutamiltransferase/isolamento & purificação , gama-Glutamiltransferase/metabolismo , Cromatografia Líquida , Cotilédone/metabolismo , Cinética , Peso Molecular , Raphanus/metabolismo , Solubilidade , Especificidade por Substrato
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