Microsporogenesis
Mostrando 13-24 de 28 artigos, teses e dissertações.
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13. O genero Dahlstedtia Malme : embriologia, sistema reprodutivo e biossistematica
Flowers, fruits and seed abortion was studied in two Brazilian species: Dahlstedtia pinnata e D. pentaphy/la (Leguminosae, Papilionoideae). Such a study was developed through investigations of: 1. floral development, microsporogenesis, ovule and early seed development following open, self- and cross-pollination, in order to compare the results to other papil
Publicado em: 2001
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14. Chromosome number and microsporogenesis in Paspalum maritimum (caespitosa group; gramineae)
Apesar da importância econômica do gênero Paspalum, pouca ou nenhuma informação citológica é encontrada para a maioria das espécies. Esta é a primeira descrição sobre número de cromossomos e comportamento meiótico para P. maritimum. Os três acessos coletados no Estado do Amapá mostraram-se tetraplóides (2n=4x=40) com os cromossomos associando
Brazilian Archives of Biology and Technology. Publicado em: 2000
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15. Identificação da enzima oxido nitrico sintase em vegetais
The enzyme nitric oxide synthase (NOS) is responsible for the synthesis of nitric oxide (NO), from the oxidation of L-arginine to L-citrulline. This enzyme has been found largely distributed in nature. In the animal kingdom, the NOS isoforms constitutively expressed are frequently Ca2+ -dependent and involved in physiological processes while Ca2+ -independen
Publicado em: 1999
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16. Caracterização citogenetica de algumas especies e hibridos interespecificos de Passiflora
ln passion ffuit breeding programs interspecific hybridization has been the best altemative in searching for diseases resistance in the Passiflora edulis f flavicarpa, the most cultivated commercial species. Studies were carried out on chromosomic characterization and meiotic behavior. The present work aimed to contribute with basic cytogenetic informations
Publicado em: 1998
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17. Cell Ablation Reveals That Expression from the Phaseolin Promoter Is Confined to Embryogenesis and Microsporogenesis.
Most previous studies of the [beta]-phaseolin (phas) gene, which encodes the major storage protein in bean (Phaseolus vulgaris L.), have shown its expression to be rigorously confined to the developing seed, both in bean and transgenic tobacco (Nicotiana tabacum L. cv Xanthi) plants. To confirm unequivocally the lack of phas expression in vegetative tissues,
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18. Analysis of Nondisjunction Induced by the R-X1 Deficiency during Microsporogenesis in Zea Mays L
The r-X1 deficiency in maize induces nondisjunction at the second mitotic division during embryo sac formation. However, it was not known if this deficiency also induces nondisjunction during the microspore divisions. Microsporogenesis in plants lacking or containing this deficiency was compared using two approaches. First, chromosome numbers were determined
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19. SPL8, an SBP-Box Gene That Affects Pollen Sac Development in Arabidopsis
SQUAMOSA PROMOTER BINDING PROTEIN–box genes (SBP-box genes) encode plant-specific proteins that share a highly conserved DNA binding domain, the SBP domain. Although likely to represent transcription factors, little is known about their role in development. In Arabidopsis, SBP-box genes constitute a structurally heterogeneous family of 16 members known as
American Society of Plant Biologists.
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20. Cytochemical Analysis of Pollen Development in Wild-Type Arabidopsis and a Male-Sterile Mutant.
Microsporogenesis has been examined in wild-type Arabidopsis thaliana and the nuclear male-sterile mutant BM3 by cytochemical staining. The mutant lacks adenine phosphoribosyltransferase, an enzyme of the purine salvage pathway that converts adenine to AMP. Pollen development in the mutant began to diverge from wild type just after meiosis, as the tetrads of
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21. Specific expression in reproductive tissues and fate of a mitochondrial sterility-associated protein in cytoplasmic male-sterile bean.
In common bean, cytoplasmic male sterility has been associated with a unique sequence found in the mitochondrial genome, designated pvs (for Phaseolus vulgaris sterility sequence). Within the pvs sequence, two open reading frames are encoded, ORF98 and ORF239. We have raised rabbit polyclonal antibodies against Pvs-ORF239 to evaluate the role of this putativ
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22. The EXCESS MICROSPOROCYTES1 gene encodes a putative leucine-rich repeat receptor protein kinase that controls somatic and reproductive cell fates in the Arabidopsis anther
Cell differentiation is essential for the development of multicellular organisms. In flowering plants, the haploid male gametophytes (pollen grains) are generated in the anther from reproductive cells called microsporocytes. Several types of somatic cells ensure successful pollen development, and thus reproduction. However, it is not clear what genes regulat
Cold Spring Harbor Laboratory Press.
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23. The SPOROCYTELESS gene of Arabidopsis is required for initiation of sporogenesis and encodes a novel nuclear protein
The formation of haploid spores marks the initiation of the gametophytic phase of the life cycle of all vascular plants ranging from ferns to angiosperms. In angiosperms, this process is initiated by the differentiation of a subset of floral cells into sporocytes, which then undergo meiotic divisions to form microspores and megaspores. Currently, there is li
Cold Spring Harbor Laboratory Press.
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24. Ovule Abortion in Arabidopsis Triggered by Stress1
Environmental stresses frequently decrease plant fertility. In Arabidopsis, the effect of salt stress on reproduction was examined using plants grown in hydroponic medium. Salt stress inhibited microsporogenesis and stamen filament elongation. Because plants grown in hydroponic media can be rapidly and transiently stressed, the minimum inductive treatment to
American Society of Plant Biologists.