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1.
Plant Cell Physiol ; 65(5): 729-736, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38288629

RESUMO

Genome-editing tools such as the clustered regularly interspaced short palindromic repeats/Cas9 (CRISPR/Cas9) system have become essential tools for increasing the efficiency and accuracy of plant breeding. Using such genome-editing tools on maize, one of the most important cereal crops of the world, will greatly benefit the agriculture and the mankind. Conventional genome-editing methods typically used for maize involve insertion of a Cas9-guide RNA expression cassette and a selectable marker in the genome DNA; however, using such methods, it is essential to eliminate the inserted DNA cassettes to avoid legislative concerns on gene-modified organisms. Another major hurdle for establishing an efficient and broadly applicable DNA-free genome-editing system for maize is presented by recalcitrant genotypes/cultivars, since cell/tissue culture and its subsequent regeneration into plantlets are crucial for producing transgenic and/or genome-edited maize. In this study, to establish a DNA-free genome-editing system for recalcitrant maize genotypes/cultivars, Cas9-gRNA ribonucleoproteins were directly delivered into zygotes isolated from the pollinated flowers of the maize-B73 cultivar. The zygotes successfully developed and were regenerated into genome-edited plantlets by co-culture with phytosulfokine, a peptide phytohormone. The method developed herein made it possible to obtain DNA- and selectable-marker-free genome-edited recalcitrant maize genotypes/cultivars with high efficiency. This method can advance the molecular breeding of maize and other important cereals, regardless of their recalcitrant characteristics.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Genoma de Planta , Zea mays , Zea mays/genética , Edição de Genes/métodos , Plantas Geneticamente Modificadas , Zigoto/metabolismo , Melhoramento Vegetal/métodos , RNA Guia de Sistemas CRISPR-Cas/genética , DNA de Plantas/genética
2.
Exp Dermatol ; 33(4): e15072, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38576105

RESUMO

Autosomal recessive congenital ichthyoses (ARCI) is a genetically heterogeneous condition that can be caused by pathogenic variants in at least 12 genes, including ABCA12. ARCI mainly consists of congenital ichthyosiform erythroderma (CIE), lamellar ichthyosis (LI) and harlequin ichthyosis (HI). The objective was to determine previously unreported pathogenic variants in ABCA12 and to update genotype-phenotype correlations for patients with pathogenic ABCA12 variants. Pathogenic variants in ABCA12 were detected using Sanger sequencing or a combination of Sanger sequencing and whole-exome sequencing. To verify the pathogenicity of a previously unreported large deletion and intron variant, cDNA analysis was performed using total RNA extracted from hair roots. Genetic analyses were performed on the patients with CIE, LI, HI and non-congenital ichthyosis with unusual phenotypes (NIUP), and 11 previously unreported ABCA12 variants were identified. Sequencing of cDNA confirmed the aberrant splicing of the variant ABCA12 in the patients with the previously unreported large deletion and intron variant. Our findings expand the phenotype spectrum of ichthyosis patients with ABCA12 pathogenic variants. The present missense variants in ABCA12 are considered to be heterogenous in pathogenicity, and they lead to varying disease severities in patients with ARCI and non-congenital ichthyosis with unusual phenotypes (NIUP).


Assuntos
Eritrodermia Ictiosiforme Congênita , Ictiose Lamelar , Ictiose , Humanos , Ictiose Lamelar/genética , Ictiose Lamelar/patologia , DNA Complementar , Genes Recessivos , Mutação , Ictiose/genética , Eritrodermia Ictiosiforme Congênita/genética , Estudos de Associação Genética , Transportadores de Cassetes de Ligação de ATP/genética
3.
Nature ; 557(7705): 392-395, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29769675

RESUMO

A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang1-3. The abundance of star-forming galaxies is known to decline4,5 from redshifts of about 6 to 10, but a key question is the extent of star formation at even earlier times, corresponding to the period when the first galaxies might have emerged. Here we report spectroscopic observations of MACS1149-JD1 6 , a gravitationally lensed galaxy observed when the Universe was less than four per cent of its present age. We detect an emission line of doubly ionized oxygen at a redshift of 9.1096 ± 0.0006, with an uncertainty of one standard deviation. This precisely determined redshift indicates that the red rest-frame optical colour arises from a dominant stellar component that formed about 250 million years after the Big Bang, corresponding to a redshift of about 15. Our results indicate that it may be possible to detect such early episodes of star formation in similar galaxies with future telescopes.

5.
Hinyokika Kiyo ; 70(2): 29-37, 2024 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-38447942

RESUMO

Bone is the most common metastatic site in prostate cancer (PCa). Although the extent of disease (EOD) grade is used for evaluating burden of bone metastasis, the accuracy of bone metastasis classification needs improvement. Bone scan index (BSI) was developed as a quantitative tool to enhance the interpretability and clinical relevance of the bone scan. This study aimed to explore the role of BSI using BONENAVI® software in determining the prognosis and treatment efficacy in castration-sensitive PCa (mCSPC) patients with bone metastasis. We retrospectively reviewed 61 mCSPC patients with bone metastasis who had received primary androgen deprivation therapy (PADT) at our institution. All patients received PADT with luteinizing hormone-releasing hormone agonist or surgical castration accompanied by first-generation antiandrogen, bicalutamide. Bone scans were performed with 99[m]Tc-MDP. BSI (%) was divided into two groups (<1.0 and ≧1.0), and BSI response rates(change at 0 months to after 6 months) were determined using thresholds of 45% decline. Castration-resistant prostate cancer (CRPC) -free survival (CRPC-FS) and Overall survival (OS) rates were analyzed using the Kaplan-Meier method. The median follow-up was 41. 9 months. Overall, 16 patients (26. 2%) died. Multivariate analysis on pretreatment factors revealed that hemoglobin (P=0.03) and BSI (P=0.04) were independent prognostic factors for OS. The 5-year OS rates in patients with low BSI and high BSI were 84.6% and 39.2%, respectively (P=0.02). In 40 patients who had a bone scan before and after PADT, OS rates in patients with a good response (≧45%) were significantly higher than those with a poor response (<45%) (P=0.001). Nadir PSA titers within 6 months after the start of treatment (P=0.005), Hb (P=0.003), and BSI change (P=0.014) were independent prognostic factors for OS. In mCSPC patients with bone metastases, BSI at diagnosis was an important predictor of CRPC progression and OS as a pre-treatment factor, and BSI change rate and PSA nadir as post-treatment factors.


Assuntos
Neoplasias Ósseas , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Antagonistas de Androgênios/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estudos Retrospectivos , Prognóstico , Resultado do Tratamento , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico
6.
Breed Sci ; 73(3): 349-353, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37840979

RESUMO

Somaclonal variation was studied by whole-genome sequencing in rice plants (Oryza sativa L., 'Nipponbare') regenerated from the zygotes, mature embryos, and immature embryos of a single mother plant. The mother plant and its seed-propagated progeny were also sequenced. A total of 338 variants of the mother plant sequence were detected in the progeny, and mean values ranged from 9.0 of the seed-propagated plants to 37.4 of regenerants from mature embryos. The natural mutation rate of 1.2 × 10-8 calculated using the variants in the seed-propagated plants was consistent with the values reported previously. The ratio of single nucleotide variants (SNVs) among the variants in the seed-propagated plants was 91.1%, which is higher than 56.1% previously reported, and not significantly different from those in the regenerants. Overall, the ratio of transitions to transversions of SNVs was lower in the regenerants as shown previously. Plants regenerated from mature embryos had significantly more variants than different progeny types. Therefore, using zygotes and immature embryos can reduce somaclonal variation during the genetic manipulation of rice.

7.
Int J Mol Sci ; 24(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38003730

RESUMO

Feeder cells and the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) in a culture medium promote mitosis and cell division in cultured cells. These are also added to nutrient medium for the cultivation of highly active in mitosis and dividing zygotes, produced in vitro or isolated from pollinated ovaries. In the study, an in vitro fertilization (IVF) system was used to study the precise effects of feeder cells and 2,4-D on the growth and development of rice (Oryza sativa L.) zygote. The elimination of 2,4-D from the culture medium did not affect the early developmental profiles of the zygotes, but decreased the division rates of multicellular embryos. The omission of feeder cells resulted in defective karyogamy, fusion between male and female nuclei, and the subsequent first division of the cultured zygotes. The culture of zygotes in a conditioned medium corrected developmental disorders. Proteome analyses of the conditioned medium revealed the presence of abundant hydrolases possibly released from the feeder cells. Exogenously applied α-amylase ameliorated karyogamy and promoted zygote development. It is suggested that hydrolytic enzymes, including α-amylase, released from feeder cells may be involved in the progression of zygotic development.


Assuntos
Oryza , Zigoto , Meios de Cultivo Condicionados/farmacologia , Mitose , Fertilização in vitro , Células Cultivadas , alfa-Amilases , Ácido 2,4-Diclorofenoxiacético
8.
Plant J ; 108(4): 1097-1115, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34538012

RESUMO

Reactive oxygen species (ROS) play essential roles in plant development and environmental stress responses. In this study, ROS dynamics, the glutathione redox status, the expression and subcellular localization of glutathione peroxidases (GPXs), and the effects of inhibitors of ROS-mediated metabolism were investigated along with fertilization and early zygotic embryogenesis in rice (Oryza sativa). Zygotes and early embryos exhibited developmental arrest upon inhibition of ROS production. Egg cells accumulated high ROS levels, and, after fertilization, intracellular ROS levels progressively declined in zygotes in which de novo expression of GPX1 and 3 was observed through upregulation of the genes. In addition to inhibition of GPX activity, depletion of glutathione impeded early embryonic development and led to failure of the zygote to appropriately decrease H2 O2 levels. Moreover, through monitoring of the glutathione redox status, the developing zygotes exhibited a progressive glutathione oxidation, which became extremely delayed under inhibited GPX activity. Our results provide insights into the importance of ROS dynamics, GPX antioxidant activity, and glutathione redox metabolism during zygotic/embryonic development.


Assuntos
Antioxidantes/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa/metabolismo , Oryza/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Glutationa Peroxidase/genética , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Oxirredução , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Zigoto
9.
Biochem Biophys Res Commun ; 622: 143-148, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-35863088

RESUMO

Pain is influenced by various factors, such as fear, anxiety, and memory. We previously reported that pain-like behaviors in mice can be induced by environmental cues in which a pain stimulus was previously presented, and that pain was reduced using fentanyl (an opioid). Although opioid analgesics are currently used to treat persistent pain, their inappropriate use causes a significant number of deaths in the United States. Thus, alternative medicines to opioids are needed. Here, we reported that SR 57227A, a serotonin type-3 receptor agonist, significantly reduced pain-like behaviors. The number of c-Fos positive cells increased by environmental cues in PFC was decreased by SR 57227A. Moreover, SR 57227A reduced pain-like behaviors of the formalin test, and restored reductions in paw withdrawal thresholds by acidic saline intramuscular injection and sciatic nerve ligation. Unlike opioids, SR 57227A induced no preference behaviors as measured by the conditioned place preference test. These data suggested that SR 57227A is an effective alternative pain reliever to opioids that targets chronic pain.


Assuntos
Agonistas do Receptor de Serotonina , Serotonina , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos Opioides/farmacologia , Analgésicos Opioides/uso terapêutico , Animais , Camundongos , Dor/tratamento farmacológico , Piperidinas , Ratos , Ratos Sprague-Dawley , Serotonina/farmacologia
10.
Blood ; 135(12): 934-947, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31972002

RESUMO

Adult T-cell leukemia/lymphoma (ATL) is a highly aggressive hematological malignancy derived from mature CD4+ T-lymphocytes. Here, we demonstrate the transcriptional regulatory network driven by 2 oncogenic transcription factors, IRF4 and NF-κB, in ATL cells. Gene expression profiling of primary ATL samples demonstrated that the IRF4 gene was more highly expressed in ATL cells than in normal T cells. Chromatin immunoprecipitation sequencing analysis revealed that IRF4-bound regions were more frequently found in super-enhancers than in typical enhancers. NF-κB was found to co-occupy IRF4-bound regulatory elements and formed a coherent feed-forward loop to coordinately regulate genes involved in T-cell functions and development. Importantly, IRF4 and NF-κB regulated several cancer genes associated with super-enhancers in ATL cells, including MYC, CCR4, and BIRC3. Genetic inhibition of BIRC3 induced growth inhibition in ATL cells, implicating its role as a critical effector molecule downstream of the IRF4-NF-κB transcriptional network.


Assuntos
Fatores Reguladores de Interferon/metabolismo , Leucemia-Linfoma de Células T do Adulto/etiologia , Leucemia-Linfoma de Células T do Adulto/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Apoptose/genética , Proteína 3 com Repetições IAP de Baculovírus/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Biologia Computacional , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Modelos Biológicos , RNA Interferente Pequeno/genética , Receptores CCR4/metabolismo
11.
Jpn J Clin Oncol ; 52(12): 1436-1440, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35959610

RESUMO

Rotationplasty is a useful option for limb salvage surgery in pediatric patients with malignant bone and soft tissue tumors. However, bone growth after rotationplasty remains poorly characterized. We present a case of a 3-year-old boy with extraskeletal Ewing sarcoma who underwent multidrug chemotherapy (vincristine, doxorubicin, ifosfamide and etoposide), wide resection and functional reconstruction with rotationplasty. No radiotherapy was administered during the treatment course and the patient has been followed up for 16 years after rotationplasty. Leg length at skeletal maturity was predicted using postoperative radiograph measurements of the affected leg at the age of 4 years. Two conventional prediction methods, the multiplier and straight-line graph methods were used for prediction. The predicted leg length was compared with the actual leg length to assess bone growth after rotationplasty. Immediately after surgery, the lengths of the affected lower leg, femur and tibia were 32.5, 15.0 and 17.6 cm, respectively, and the predicted leg length of the affected leg at skeletal maturity using the multiplier and straight-line graph methods was 44.6 and 44.2 cm, respectively. However, the actual length of the affected leg at skeletal maturity was 49.8 cm, and the gap between actual and predicted lengths was more than 5 cm. In conclusion, the affected leg after rotationplasty showed more than expected bone overgrowth compared with the predictions of the conventional methods.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Masculino , Criança , Humanos , Pré-Escolar , Sarcoma de Ewing/diagnóstico por imagem , Sarcoma de Ewing/cirurgia , Perna (Membro) , Seguimentos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia
12.
J Plant Res ; 135(4): 627-633, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35534650

RESUMO

Setaria viridis, the wild ancestor of foxtail millet (Setaria italica), is an effective model plant for larger C4 crops because S. viridis has several desirable traits, such as short generation time, prolific seed production and a small genome size. These advantages are well suited for investigating molecular mechanisms in angiosperms, especially C4 crop species. Here, we report a procedure for isolating gametes and zygotes from S. viridis flowers. To isolate egg cells, ovaries were harvested from unpollinated mature flowers and cut transversely, which allowed direct access to the embryo sac. Thereafter, an egg cell was released from the cut end of the basal portion of the dissected ovary. To isolate sperm cells, pollen grains released from anthers were immersed in a mannitol solution, resulting in pollen-grain bursting, which released sperm cells. Additionally, S. viridis zygotes were successfully isolated from freshly pollinated flowers. Isolated zygotes cultured in a liquid medium developed into globular-like embryos and cell masses. Thus, isolated S. viridis gametes, zygotes and embryos are attainable for detailed observations and investigations of fertilization and developmental events in angiosperms.


Assuntos
Setaria (Planta) , Flores , Pólen , Sementes , Setaria (Planta)/genética , Zigoto
13.
Proc Natl Acad Sci U S A ; 116(19): 9652-9657, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31000601

RESUMO

Epigenetic reprogramming is required for proper regulation of gene expression in eukaryotic organisms. In Arabidopsis, active DNA demethylation is crucial for seed viability, pollen function, and successful reproduction. The DEMETER (DME) DNA glycosylase initiates localized DNA demethylation in vegetative and central cells, so-called companion cells that are adjacent to sperm and egg gametes, respectively. In rice, the central cell genome displays local DNA hypomethylation, suggesting that active DNA demethylation also occurs in rice; however, the enzyme responsible for this process is unknown. One candidate is the rice REPRESSOR OF SILENCING1a (ROS1a) gene, which is related to DME and is essential for rice seed viability and pollen function. Here, we report genome-wide analyses of DNA methylation in wild-type and ros1a mutant sperm and vegetative cells. We find that the rice vegetative cell genome is locally hypomethylated compared with sperm by a process that requires ROS1a activity. We show that many ROS1a target sequences in the vegetative cell are hypomethylated in the rice central cell, suggesting that ROS1a also demethylates the central cell genome. Similar to Arabidopsis, we show that sperm non-CG methylation is indirectly promoted by DNA demethylation in the vegetative cell. These results reveal that DNA glycosylase-mediated DNA demethylation processes are conserved in Arabidopsis and rice, plant species that diverged 150 million years ago. Finally, although global non-CG methylation levels of sperm and egg differ, the maternal and paternal embryo genomes show similar non-CG methylation levels, suggesting that rice gamete genomes undergo dynamic DNA methylation reprogramming after cell fusion.


Assuntos
DNA Glicosilases , Metilação de DNA/fisiologia , DNA de Plantas , Oryza , Proteínas de Plantas , Pólen , Arabidopsis/enzimologia , Arabidopsis/genética , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , DNA de Plantas/genética , DNA de Plantas/metabolismo , Oryza/enzimologia , Oryza/genética , Óvulo Vegetal/enzimologia , Óvulo Vegetal/genética , Desenvolvimento Vegetal/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/enzimologia , Pólen/genética
14.
Molecules ; 27(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35164343

RESUMO

Since the efficiency in the transcription of the HIV genome contributes to the success of viral replication and infectivity, we investigated the downregulating effects of the spirobisindole alkaloids globospiramine (1), deoxyvobtusine (2), and vobtusine lactone (3) from the endemic Philippine medicinal plant, Voacanga globosa, during HIV gene transcription. Alkaloids 1-3 were explored for their inhibitory activity on TNF-α-induced viral replication in two latently HIV-infected cell lines, OM10.1 and J-Lat. The induction of HIV replication from OM10.1 and J-Lat cells elicited by TNF-α was blocked by globospiramine (1) within noncytotoxic concentrations. Furthermore, globospiramine (1) was found to target the NF-ĸB activation cascade in a dose-dependent manner when the transcriptional step at which inhibitory activity is exerted was examined in TNF-α-induced 293 human cells using transient reporter (luciferase) gene expression systems (HIV LTR-luc, ĸB-luc, and mutant ĸB-luc). Interrogation through molecular docking against the NF-ĸB p50/p65 heterodimer and target sites of the subunits comprising the IKK complex revealed high binding affinities of globospiramine (1) against the S281 pocket of the p65 subunit (BE = -9.2 kcal/mol) and the IKKα activation loop (BE = -9.1 kcal/mol). These findings suggest globospiramine (1) as a molecular inspiration to discover new alkaloid-based anti-HIV derivatives.


Assuntos
Alcaloides/farmacologia , Infecções por HIV/metabolismo , HIV-1/fisiologia , Quinase I-kappa B/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Voacanga/química , Alcaloides/química , Linhagem Celular , Relação Dose-Resposta a Droga , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Células HL-60 , Humanos , Quinase I-kappa B/química , Alcaloides Indólicos/farmacologia , Modelos Biológicos , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B/química , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Compostos de Espiro/farmacologia , Fator de Transcrição RelA/química , Fator de Necrose Tumoral alfa/farmacologia , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
15.
Rinsho Ketsueki ; 63(11): 1508-1512, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-36476789

RESUMO

A 78-year-old man with prostate squamous cell carcinoma recurrence in his pelvis was admitted to our hospital. Rectal obstruction led to creation of an artificial anus on the transverse colon. Then, docetaxel and radiation therapies were started. A week later, severe hematuria and melena occurred. Activated partial thromboplastin time (APTT) and prothrombin time (PT) were extremely prolonged. Cross-mixing test for APTT and PT revealed an inhibitor pattern, which was diagnosed as acquired factor V inhibitor. Fresh frozen plasma and vitamin K infusions were ineffective, but platelet transfusion successfully stopped the bleeding. Platelet factor V derived from megakaryocytes may affect local hemostasis. The patient received prednisolone (PSL), and the inhibitor disappeared on day 70 and was in remission. PSL could be stopped on day 100. Later, we demonstrated APTT and PT shortening of factor V deficient plasma by the supernatant of activated platelets with collagen.


Assuntos
Carcinoma de Células Escamosas , Próstata , Humanos , Masculino , Idoso , Transfusão de Plaquetas , Fator V
16.
New Phytol ; 232(6): 2369-2383, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34545570

RESUMO

Hybridization plays a decisive role in the evolution and diversification of angiosperms. However, the mechanisms of wide hybridization remain open because pre- and post-fertilization barriers limit the production and development of inter-subfamily/intergeneric zygotes, respectively. We examined hybridization between wheat and rice using an in vitro fertilization (IVF) system to bypass these barriers. Several gamete combinations of allopolyploid wheat-rice hybrid zygotes were successfully produced, and the developmental profiles of hybrid zygotes were analyzed. Hybrid zygotes derived from one rice egg cell and one wheat sperm cell ceased at the multicellular embryo-like structure stage. This developmental barrier was overcome by adding one wheat egg cell to the wheat-rice hybrid zygote. In the reciprocal combination, one wheat egg and one rice sperm cell, the resulting hybrid zygotes failed to divide. However, doubling the dosage of rice sperm cell allowed the hybrid zygotes to develop into plantlets. Rice chromosomes appeared to be progressively eliminated during the early developmental stage of these hybrid embryos, and c. 20% of regenerated plants showed abnormal morphology. These results suggest that hybrid breakdown can be overcome through optimization of gamete combinations, and the present hybrid will provide a new horizon for utilization of inter-subfamily genetic resources.


Assuntos
Oryza , Zigoto , Fertilização in vitro , Oryza/genética , Sementes/genética , Triticum/genética
17.
Plant Cell Rep ; 40(3): 575-582, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33439322

RESUMO

KEY MESSAGE: We found that mutations in a Ca2+-permeable mechanosensitive channel MCA1, an ethylene-regulated microtubule-associated protein WDL5, and a versatile co-receptor BAK1 affect root growth response to mechanical stress. Plant root tips exposed to mechanical impedance show a temporal reduction in the elongation growth. The process involves a transient Ca2+ increase in the cytoplasm followed by ethylene signaling. To dissect the molecular mechanisms underlying this response, we examined the root growth of a series of Arabidopsis mutants with potentially altered response to mechanical stress after transfer from vertical to horizontal plates that were covered by dialysis membrane as an impedance. Among the plant hormone-response mutants tested, the ethylene-insensitive mutant ein3 was confirmed to show no growth reduction after the transfer. The root growth reduction was attenuated in a mutant of MCA1 encoding a Ca2+-permeable mechanosensitive channel and that of WDL5 encoding an ethylene-regulated microtubule-associated protein. We also found that the growth reduction was enhanced in a mutant of BAK1 encoding a co-receptor that pairs with numerous leucine-rich repeat receptor kinases to modulate growth and immunity. These results suggest the root growth reduction in response to mechanical stress involves ethylene-mediated microtubule reorganization and also transmembrane receptor-mediated signal transduction.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Arabidopsis/genética , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Gravitropismo/fisiologia , Proteínas de Membrana/genética , Meristema/crescimento & desenvolvimento , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/metabolismo , Mutação , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Estresse Fisiológico
18.
J Card Surg ; 36(12): 4776-4778, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34585432

RESUMO

Anomalous aortic origin of a coronary artery from the opposite sinus is a rare congenital condition that can cause sudden death in young people. When it is associated with acute aortic dissection, acute myocardial infarction can occur due to enlargement of the sinus of Valsalva. We report the case of a 71-year-old man with anomalous origin of the right coronary artery from the left sinus of Valsalva, who developed right ventricular infarction due to the compression of the right coronary artery between the aorta and pulmonary artery trunk.


Assuntos
Dissecção Aórtica , Anomalias dos Vasos Coronários , Infarto do Miocárdio , Seio Aórtico , Adolescente , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aorta , Angiografia Coronária , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/cirurgia , Humanos , Masculino , Seio Aórtico/diagnóstico por imagem , Seio Aórtico/cirurgia
19.
Plant J ; 100(2): 374-383, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31257654

RESUMO

In Arabidopsis, spermine is produced in most tissues and has been implicated in stress response, while its structural isomer thermospermine is only in xylem precursor cells. Studies on acaulis5 (acl5), a mutant defective in the biosynthesis of thermospermine, have revealed that thermospermine plays a repressive role in xylem development through enhancement of mRNA translation of the SAC51 family. In contrast, the pao5 mutant defective in the degradation of thermospermine has high levels of thermospermine and shows increased salt tolerance, suggesting a role of thermospermine in salt stress response. Here we compared acl5 with a mutant of spermine synthase, spms, in terms of abiotic stress tolerance and found that acl5 was much more sensitive to sodium than the wild-type and spms. A double-mutant of acl5 and sac51-d, which suppresses the excessive xylem phenotype of acl5, recovered normal sensitivity, while a quadruple T-DNA insertion mutant of the SAC51 family, which has an increased thermospermine level but shows excessive xylem development, showed increased salt sensitivity, unlike pao5. Together with the result that the salt tolerance of both wild-type and acl5 seedlings was improved by long-term treatment with thermospermine, we suggest a correlation of the salt tolerance with reduced xylem development rather than with the thermospermine level. We further found that the mutants containing high thermospermine levels showed increased tolerance to drought and heat stress, suggesting another role of thermospermine that may be common with that of spermine and secondary to that in restricting excess xylem development associated with salt hypersensitivity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Espermina/análogos & derivados , Xilema/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Espermina/metabolismo
20.
Mol Reprod Dev ; 87(3): 374-379, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31736192

RESUMO

Polyploidization has played a major role in the long-term diversification and evolutionary success of angiosperms. Triploid formation among diploid plants, which is generally considered to be achieved by fertilization of an unreduced gamete with a reduced one, has been accepted as a means of polyploid production. In addition, it has been supposed that polyspermy also contributes to the triploid formation in maize, wheat, and some orchids; however, such a mechanism has been considered uncommon because reproducing the polyspermic situation and unambiguously investigating developmental profiles of polyspermic zygotes are difficult. To overcome these problems, rice polyspermic zygotes have been successfully produced by electrofusion of an egg cell with two sperm cells, and their developmental profiles have been monitored. The triploid zygotes progress through karyogamy and divide into two-celled embryos via a typical bipolar mitotic division; the two-celled embryos further develop into triploid plants, indicating that polyspermic plant zygotes, unlike those of animals, can develop normally. Furthermore, progenies consisting of triparental genetic materials have been successfully obtained in Arabidopsis through the pollination of two different kinds of male parents with a female parent. These different pieces of evidence for development and emergence of polyspermic zygotes in vitro and in planta suggest that polyspermy is a key event in polyploidization and species diversification.


Assuntos
Diploide , Oryza/citologia , Oryza/genética , Interações Espermatozoide-Óvulo/fisiologia , Triploidia , Animais , Feminino , Masculino , Oócitos/metabolismo , Sementes/metabolismo , Espermatozoides/metabolismo , Zigoto/metabolismo
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