Base de dados : MEDLINE
Pesquisa : A18.024.249.500.249.249 [Categoria DeCS]
Referências encontradas : 482 [refinar]
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[PMID]:28450583
[Au] Autor:Zhao X; Bramsiepe J; Van Durme M; Komaki S; Prusicki MA; Maruyama D; Forner J; Medzihradszky A; Wijnker E; Harashima H; Lu Y; Schmidt A; Guthörl D; Logroño RS; Guan Y; Pochon G; Grossniklaus U; Laux T; Higashiyama T; Lohmann JU; Nowack MK; Schnittger A
[Ad] Endereço:Department of Developmental Biology, Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany.
[Ti] Título:RETINOBLASTOMA RELATED1 mediates germline entry in .
[So] Source:Science;356(6336), 2017 04 28.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To produce seeds, flowering plants need to specify somatic cells to undergo meiosis. Here, we reveal a regulatory cascade that controls the entry into meiosis starting with a group of redundantly acting cyclin-dependent kinase (CDK) inhibitors of the KIP-RELATED PROTEIN (KRP) class. KRPs function by restricting CDKA;1-dependent inactivation of the Retinoblastoma homolog RBR1. In and triple mutants, designated meiocytes undergo several mitotic divisions, resulting in the formation of supernumerary meiocytes that give rise to multiple reproductive units per future seed. One function of RBR1 is the direct repression of the stem cell factor ( ), which ectopically accumulates in meiocytes of triple and mutants. Depleting in mutants restored the formation of only a single meiocyte.
[Mh] Termos MeSH primário: Proteínas de Arabidopsis/metabolismo
Arabidopsis/embriologia
Proteínas de Homeodomínio/metabolismo
Óvulo Vegetal/embriologia
[Mh] Termos MeSH secundário: Arabidopsis/genética
Proteínas de Arabidopsis/genética
Proteínas de Transporte/genética
Proteínas de Transporte/metabolismo
Proteínas Inibidoras de Quinase Dependente de Ciclina/genética
Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo
Proteínas de Homeodomínio/genética
Meiose/genética
Meiose/fisiologia
Mutação
Óvulo Vegetal/genética
Óvulo Vegetal/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 0 (Carrier Proteins); 0 (Cyclin-Dependent Kinase Inhibitor Proteins); 0 (Homeodomain Proteins); 0 (KRP4 protein, Arabidopsis); 0 (KRP6 protein, Arabidopsis); 0 (KRP7 protein, Arabidopsis); 0 (RBR1 protein, Arabidopsis); 0 (WUSCHEL protein, Arabidopsis)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171219
[Lr] Data última revisão:
171219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE


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[PMID]:28961769
[Au] Autor:Bogaert KA; Beeckman T; De Clerck O
[Ad] Endereço:Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium.
[Ti] Título:Egg activation-triggered shape change in the Dictyota dichotoma (Phaeophyceae) zygote is actin-myosin and secretion dependent.
[So] Source:Ann Bot;120(4):529-538, 2017 Oct 17.
[Is] ISSN:1095-8290
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Background and Aims: Cellular morphogenesis in land plants and brown algae is typically a slow process involving growth established by an interplay of turgor pressure and cell wall rigidity. However, a recent study showed that zygotes of the brown alga Dictyota dichotoma undergo a rapid shape change from a sphere to an elongated spheroid in about 90 s, establishing the first body axis. Methods: Using a combination of pharmacology, staining techniques, membrane depolarization and microscopy techniques (brightfield, transmission electron microscopy and confocal laser scanning microscopy), egg activation and the shape change of the egg cell of D. dichotoma was studied. Key Results: It was established that elongation of the zygote does not involve growth, i.e. a positive change in size. The elongation is dependent on F-actin and myosin but independent of microtubules. Secretion was also found to be necessary for elongation after addition of brefeldin A. Moreover, a temporal correlation between extracellular matrix secretion and elongation was observed. Ionomycin and high potassium seawater are capable of triggering the onset of elongation, suggesting a role for membrane depolarization and calcium influx in the signalling mechanism. The elongated cells are shorter in the presence of ionomycin, suggesting a role for calcium in elongation. Conclusions: A model is proposed in which the fast elongation of the fertilized egg in Dictyota is accomplished by a force generated by F-actin and myosin, regulated by cytoplasmic calcium concentrations and by secretion during elongation lowering the antagonistic force. The finding of early extracellular matrix secretion, membrane depolarization and ionophore-triggered egg activation suggest significant differences in the mechanism of egg activation signalling between D. dichotoma and the oogamous brown algal model system Fucus .
[Mh] Termos MeSH primário: Actinas/fisiologia
Miosinas/fisiologia
Óvulo Vegetal/fisiologia
Feófitas/fisiologia
Sementes/fisiologia
[Mh] Termos MeSH secundário: Microscopia Confocal
Microscopia Eletrônica de Transmissão
Óvulo Vegetal/anatomia & histologia
Óvulo Vegetal/ultraestrutura
Feófitas/metabolismo
Feófitas/ultraestrutura
Sementes/anatomia & histologia
Sementes/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Actins); EC 3.6.4.1 (Myosins)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170930
[St] Status:MEDLINE
[do] DOI:10.1093/aob/mcx085


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[PMID]:28672040
[Au] Autor:Tang P; Zhang Q; Yao X
[Ad] Endereço:Key Laboratory of Plant Germplasm Enhancement and Speciality Agriculture, Wuhan Botanical Garden, the Chinese Academy of Sciences, Wuhan, Hubei, China.
[Ti] Título:Comparative transcript profiling explores differentially expressed genes associated with sexual phenotype in kiwifruit.
[So] Source:PLoS One;12(7):e0180542, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Kiwifruit is a perennial, deciduous and functionally dioecious plant. However, very little is known about the whole-genome molecular mechanisms contributing to distinct sexual phenotypes. To gain a global view of genes differentially expressed between male and female flowers, we analyzed genome-wide gene expression profiles in the flowers of male and female plants using high-throughput RNA sequencing. RESULTS: A total of 53.5 million reads were generated. Based on the alignments of unigenes to kiwifruit genome predicted genes, a total of 39,040 unique genes with a mean length of 970 bp were identified. There were 2,503 UniGenes differentially expressed between female and male flowers, with 1,793 up-regulated and 710 down-regulated in the female flowers. Moreover, the gene expression pattern of 17 out of 19 unigenes differentially expressed between male and female flowers revealed by RNA-Seq was confirmed by real-time quantitative PCR (qRT-PCR). CONCLUSIONS: Here, we obtained a large number of EST sequences from female and male flowers of kiwifruit. This comparative transcriptome analysis provides an invaluable resource for gene expression, genomics, and functional genomic studies in A. chinensis and its related species. This study also represents a first step toward the investigation of genes involved in kiwifruit sex determination.
[Mh] Termos MeSH primário: Actinidia/genética
Perfilação da Expressão Gênica
Genes de Plantas
RNA Mensageiro/genética
[Mh] Termos MeSH secundário: Óvulo Vegetal
Pólen
Análise de Sequência de RNA
Transcriptoma
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Messenger)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170704
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180542


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[PMID]:28665990
[Au] Autor:Yamamoto K; Kawai-Toyooka H; Hamaji T; Tsuchikane Y; Mori T; Takahashi F; Sekimoto H; Ferris PJ; Nozaki H
[Ad] Endereço:Department of Biological Sciences, Graduate School of Science, the University of Tokyo, Bunkyo-ku, Tokyo, Japan.
[Ti] Título:Molecular evolutionary analysis of a gender-limited MID ortholog from the homothallic species Volvox africanus with male and monoecious spheroids.
[So] Source:PLoS One;12(6):e0180313, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Volvox is a very interesting oogamous organism that exhibits various types of sexuality and/or sexual spheroids depending upon species or strains. However, molecular bases of such sexual reproduction characteristics have not been studied in this genus. In the model species V. carteri, an ortholog of the minus mating type-determining or minus dominance gene (MID) of isogamous Chlamydomonas reinhardtii is male-specific and determines the sperm formation. Male and female genders are genetically determined (heterothallism) in V. carteri, whereas in several other species of Volvox both male and female gametes (sperm and eggs) are formed within the same clonal culture (homothallism). To resolve the molecular basis of the evolution of Volvox species with monoecious spheroids, we here describe a MID ortholog in the homothallic species V. africanus that produces both monoecious and male spheroids within a single clonal culture. Comparison of synonymous and nonsynonymous nucleotide substitutions in MID genes between V. africanus and heterothallic volvocacean species suggests that the MID gene of V. africanus evolved under the same degree of functional constraint as those of the heterothallic species. Based on semi quantitative reverse transcription polymerase chain reaction analyses using the asexual, male and monoecious spheroids isolated from a sexually induced V. africanus culture, the MID mRNA level was significantly upregulated in the male spheroids, but suppressed in the monoecious spheroids. These results suggest that the monoecious spheroid-specific down regulation of gene expression of the MID homolog correlates with the formation of both eggs and sperm in the same spheroid in V. africanus.
[Mh] Termos MeSH primário: Evolução Molecular
Genes de Plantas
Pólen
Esferoides Celulares
Volvox/genética
[Mh] Termos MeSH secundário: Southern Blotting
Óvulo Vegetal
Filogenia
Reação em Cadeia da Polimerase
Reprodução
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Especificidade da Espécie
Volvox/classificação
Volvox/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170701
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180313


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[PMID]:28651518
[Au] Autor:Liu L; Wang D; Meng M; Xue J
[Ad] Endereço:College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China.
[Ti] Título:Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance.
[So] Source:BMC Evol Biol;17(1):149, 2017 Jun 26.
[Is] ISSN:1471-2148
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. RESULTS: New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. CONCLUSIONS: Cosmosperma further demonstrates diversification of frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures.
[Mh] Termos MeSH primário: Evolução Biológica
Plantas/genética
[Mh] Termos MeSH secundário: Extremo Oriente
Fósseis
Óvulo Vegetal/anatomia & histologia
Óvulo Vegetal/fisiologia
Folhas de Planta/anatomia & histologia
Folhas de Planta/fisiologia
Fenômenos Fisiológicos Vegetais
Caules de Planta/anatomia & histologia
Plantas/anatomia & histologia
Plantas/classificação
Pólen/anatomia & histologia
Pólen/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE
[do] DOI:10.1186/s12862-017-0992-1


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[PMID]:28430814
[Au] Autor:Zhang X; Liu W; Wang X
[Ad] Endereço:College of Forestry, Northwest A&F University, Yangling, China.
[Ti] Título:How the ovules get enclosed in magnoliaceous carpels.
[So] Source:PLoS One;12(4):e0174955, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Angiosperms distinguish themselves from gymnosperms by their ovules that are enclosed before pollination. However, how the ovules get enclosed in angiosperms remains a mystery, especially for Magnoliaceae. The only key to this mystery is finding a series of carpels transitional from fully closed with enclosed ovules to open with naked ovules. We use routine paraffin section technology, LM, SEM to document the morphology and anatomy of carpel variation in Michelia figo (Magnoliaceae). A series of carpel variations within a single flower of Michelia figo (Magnoliaceae) are documented, in which the ovules are exposed in atypical carpels. These atypical and typical carpels for the first time demonstrate clearly how the naked ovule get enclosed. Each atypical carpel, with naked ovules, clearly comprises two parts, namely, subtending foliar part and branches bearing ovules, suggesting that a typical carpel is actually an end-product of the fusion between the ovuliferous branches and subtending foliar parts. The only difference among these carpels is the extent of fusion between these two parts. This generalization is in full agreement with the molecular genetic studies on angiosperm flowers.
[Mh] Termos MeSH primário: Magnoliopsida/fisiologia
Óvulo Vegetal/fisiologia
[Mh] Termos MeSH secundário: Microscopia Eletrônica de Varredura
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170422
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174955


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[PMID]:28267957
[Au] Autor:Zhou LZ; Juranic M; Dresselhaus T
[Ad] Endereço:Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
[Ti] Título:Germline Development and Fertilization Mechanisms in Maize.
[So] Source:Mol Plant;10(3):389-401, 2017 Mar 06.
[Is] ISSN:1752-9867
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Maize is the most important agricultural crop used for food, feed, and biofuel as well as a raw material for industrial products such as packaging material. To increase yield and to overcome hybridization barriers, studies of maize gamete development, the pollen tube journey, and fertilization mechanisms were initiated more than a century ago. In this review, we summarize and discuss our current understanding of the regulatory components for germline development including sporogenesis and gametogenesis, the progamic phase of pollen germination and pollen tube growth and guidance, as well as fertilization mechanisms consisting of pollen tube arrival and reception, sperm cell release, fusion with the female gametes, and egg cell activation. Mechanisms of asexual seed development are not considered here. While only a few molecular players involved in these processes have been described to date and the underlying mechanisms are far from being understood, maize now represents a spearhead of reproductive research for all grass species. Recent development of essentially improved transformation and gene-editing systems may boost research in this area in the near future.
[Mh] Termos MeSH primário: Zea mays/crescimento & desenvolvimento
Zea mays/metabolismo
[Mh] Termos MeSH secundário: Fertilização/genética
Fertilização/fisiologia
Óvulo Vegetal/genética
Óvulo Vegetal/crescimento & desenvolvimento
Óvulo Vegetal/metabolismo
Proteínas de Plantas/genética
Proteínas de Plantas/metabolismo
Tubo Polínico/genética
Tubo Polínico/crescimento & desenvolvimento
Tubo Polínico/metabolismo
Zea mays/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Plant Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170308
[St] Status:MEDLINE


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[PMID]:28228439
[Au] Autor:Gilles LM; Khaled A; Laffaire JB; Chaignon S; Gendrot G; Laplaige J; Bergès H; Beydon G; Bayle V; Barret P; Comadran J; Martinant JP; Rogowsky PM; Widiez T
[Ad] Endereço:Laboratoire Reproduction et Développement des Plantes, Univ Lyon ENS de Lyon UCB Lyon 1 CNRS, INRA, Lyon, France.
[Ti] Título:Loss of pollen-specific phospholipase NOT LIKE DAD triggers gynogenesis in maize.
[So] Source:EMBO J;36(6):707-717, 2017 Mar 15.
[Is] ISSN:1460-2075
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Gynogenesis is an asexual mode of reproduction common to animals and plants, in which stimuli from the sperm cell trigger the development of the unfertilized egg cell into a haploid embryo. Fine mapping restricted a major maize QTL (quantitative trait locus) responsible for the aptitude of inducer lines to trigger gynogenesis to a zone containing a single gene ( ) coding for a patatin-like phospholipase A. In all surveyed inducer lines, carries a 4-bp insertion leading to a predicted truncated protein. This frameshift mutation is responsible for haploid induction because complementation with wild-type abolishes the haploid induction capacity. Activity of the promoter is restricted to mature pollen and pollen tube. The translational NLD::citrine fusion protein likely localizes to the sperm cell plasma membrane. In roots, the truncated protein is no longer localized to the plasma membrane, contrary to the wild-type NLD protein. In conclusion, an intact pollen-specific phospholipase is required for successful sexual reproduction and its targeted disruption may allow establishing powerful haploid breeding tools in numerous crops.
[Mh] Termos MeSH primário: Óvulo Vegetal/crescimento & desenvolvimento
Fosfolipases/metabolismo
Proteínas de Plantas/metabolismo
Pólen/enzimologia
Reprodução
Zea mays/fisiologia
[Mh] Termos MeSH secundário: Regulação da Expressão Gênica de Plantas
Fosfolipases/deficiência
Zea mays/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Plant Proteins); EC 3.1.- (Phospholipases)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170224
[St] Status:MEDLINE
[do] DOI:10.15252/embj.201796603


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[PMID]:28198089
[Au] Autor:Champagne A; Boutry M
[Ad] Endereço:Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
[Ti] Título:A comprehensive proteome map of glandular trichomes of hop (Humulus lupulus L.) female cones: Identification of biosynthetic pathways of the major terpenoid-related compounds and possible transport proteins.
[So] Source:Proteomics;17(8), 2017 Apr.
[Is] ISSN:1615-9861
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Female flowers of hop (Humulus lupulus) are an essential source of terpenoid-related compounds, which are mainly used as flavoring in the beer brewing process. The compounds involved are bitter acids, terpenophenolics, as well as mono- and sesquiterpenoids. In this work, we analyzed the proteome of purified glandular trichomes (lupulin glands) from female flowers, which produce and accumulate these compounds. An extensive 2D-LC-MS/MS analysis identified 1015 proteins. Of these, most correspond to housekeeping and primary metabolism-related proteins, albeit predominantly including amino acid and lipid metabolism, which feeds the specialized (secondary) metabolism. Indeed, 75 proteins belong to the specialized metabolism. No less than 40 enzymes are involved in the synthesis of terpenoid-derived compounds and 21 are predicted transporters, some of which might be involved in the transport of specialized metabolites. We discuss the possible routes involved in the intra- and intercellular translocation of terpenoids and their precursors. This comprehensive proteomic map of the glandular trichomes of hop female flowers represents a valuable resource to improve our knowledge on the function of glandular trichomes.
[Mh] Termos MeSH primário: Humulus/metabolismo
Proteínas de Plantas/metabolismo
Proteoma/análise
Terpenos/metabolismo
Tricomas/metabolismo
[Mh] Termos MeSH secundário: Vias Biossintéticas
Proteínas de Transporte/metabolismo
Óvulo Vegetal/metabolismo
Prenilação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carrier Proteins); 0 (Plant Proteins); 0 (Proteome); 0 (Terpenes)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170621
[Lr] Data última revisão:
170621
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170216
[St] Status:MEDLINE
[do] DOI:10.1002/pmic.201600411


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[PMID]:28137704
[Au] Autor:Losada JM; Herrero M
[Ad] Endereço:Arnold Arboretum of Harvard University, 1300 Centre St, Boston, MA 02131, USA.
[Ti] Título:Pollen tube access to the ovule is mediated by glycoprotein secretion on the obturator of apple (Malus × domestica, Borkh).
[So] Source:Ann Bot;119(6):989-1000, 2017 Apr 01.
[Is] ISSN:1095-8290
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Background and Aims: Within the ovary, the obturator bridges the pathway of the pollen tube from the style to the ovule. Despite its widespread presence among flowering plants, its function has only been studied in a handful of species, and the molecules involved in pollen tube-obturator cross-talk have not been explored hitherto. This work evaluates the involvement of glucans and glycoproteins on pollen tube growth in the obturator of apple flowers ( Malus × domestica) . Methods: Pollen tube kinetics were sequentially examined in the pistil and related to changes occurring on the obturator using histochemistry and inmunocytochemistry. To discriminate between changes in the obturator induced by pollen tubes from those developmentally regulated, both pollinated and unpollinated pistils were examined. Key Results: Pollen tube growth rates were slow in the stigma, faster in the style and slow again in the ovary. The arrival of pollen tubes at the obturator was concomitant with the secretion of proteins, saccharides and glycoprotein epitopes belonging to extensins and arabinogalactan proteins (AGPs). While some of these secretions - extensins and AGPs labelled by JIM13 - were developmentally regulated, others - AGPs labelled by JIM8 - were elicited by the presence of pollen tubes. Following pollen tube passage, all these glycoproteins were depleted. Conclusions: The results show a timely secretion of glycoproteins on the obturator surface concomitant with pollen tube arrival at this structure. The fact that their secretion is depleted following pollen tube passage strongly suggests their role in regulating pollen tube access to the ovule. Remarkably, both the regulation of the secretion of the different glycoproteins, as well as their association with the performance of pollen tubes exhibit similarities with those observed in the stigma, in line with their common developmental origin.
[Mh] Termos MeSH primário: Glucanos/metabolismo
Glicoproteínas/metabolismo
Malus/fisiologia
Óvulo Vegetal/fisiologia
Proteínas de Plantas/metabolismo
Tubo Polínico/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glucans); 0 (Glycoproteins); 0 (Plant Proteins)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170201
[St] Status:MEDLINE
[do] DOI:10.1093/aob/mcw276



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BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde