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1.
A polyclonal antiserum and monoclonal antibodies have been prepared to purified pollen exines of Calocedrus decurrens Florin. The location of the antigen is in the exine, as shown by light-and electron-microscopic immunocytochemistry. The greatest reduction in antibody binding follows treatment of the exine with chemicals known to alter sporopollenin. These results provide evidence that sporopollenin is antigenic. Exines of ten species of gymnosperms and angiosperms also bound the polyclonal antiserum, indicating similarity of sporopollenin structure. 相似文献
2.
JENNIFER M. EDMONDS F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1984,88(3):237-251
J. M. EDMONDS, 1984. Pollen morphology of Solanum L. section Solnnum . The pollen morphology of both dried and fresh, fixed material was examined using SEM. The work confirmed thc spheroidal to sub-prolate shape, the tricolporate nature and the granular surface sculpturing, typical of Solanurn pollen, but failed to demonstrate the occurrence of exine patterns which could bc of practical taxonomic use is differentiating the species belonging to the section Solanurn . Quantification of the exine sculpturing, by means of granule density counts, indicated a possible relationship between this feature and the morpho-genetic diversity of certain species. 相似文献
3.
Masamichi Takahashi 《Journal of plant research》1989,102(2):219-234
Development of the echinate pollen grains inFarfugium (Compositae: Senecioneae) has been studied by a combination of transmission electron microscopy and field emission scanning
electron microscopy with a freeze fractured method. The inner surface of the callose wall surrounding each microspore does
not possess an echinate pattern before primexine deposition begins. The primexine formation coincides with the initiation
of spines. The freeze fractured primexine shows probacula which form transverse rods. The developing exine has an inner spongy
substructure. The endexine is formed by the accumulation of the electron dense lamellae with white lines after the dissolution
of the callose wall. In the present study, it is confirmed that the developmental process of pollen formation revealed in
the field emission scanning electron microscope is consistent with the results obtained using the transmission electron microscope. 相似文献
4.
Subunits of forming pollen exine and Ubisch bodies as seen in freeze substitutedLedebouria socialis Roth (Hyacinthaceae) 总被引:1,自引:0,他引:1
Summary High-pressure freezing/freeze substitution/TEM was employed to investigate anthers of the monocotyledonous angiospermLedebouria socialis Roth (Hyacinthaceae) during early tetrad stage. The initials of the outer sporopollenous pollen wall stratum (=sexine) and of the homologous tapetal products (=Ubisch bodies) are composed of highly regular subunits: clustered globules with a constant diameter of approximately 28 nm. The clusters develop within diffuse accumulations of electron-dense material. This process, interpreted as sporopollenin polymerization, does not necessarily depend on the presence of membrane-bound enzymes. Immunogold labeling with JIM 5 and JIM 7 antibodies revealed that the primexine as well as the dissolving tapetal cell walls, the sites of sexine and Ubisch body formation, respectively, contain un-esterified and methyl-esterified pectins.Abbreviations E-PTA
ethanolic phosphotungstic acid
- PA
periodic acid
- UA/Pb
uranyl acetate/lead 相似文献
5.
6.
Summary. We present the results of ultrastructural and immunocytochemical studies of sugar beet microsporocytes during the developmental
phase that begins with the first meiotic metaphase and ends with the formation of young tetrads. The most prominent feature
noted during this period of microsporogenesis was the presence of numerous cisternae of endoplasmic reticulum which frequently
lie perpendicular to the surface of the plasma membrane and eventually fuse to it. Microscopic observations have been combined
with the detection of several carbohydrate epitopes representing pectins and arabinogalactan proteins in the primexine and
incipient exine. Pectin domains that possess both low and highly methylesterified epitopes, as well as pectin side chains
enriched in (1→4)-β-D-galactose residues, are deposited in this young microspore wall. The epitopes of arabinogalactan protein
that bind to JIM13, JIM8, and LM2 antibodies are localised within the callose wall surrounding posttelophase tetrads. The
possibility of endoplasmic-reticulum involvement in the synthesis, transport, or metabolism of several microspore wall compounds
is discussed.
Correspondence and reprints: Institute of Plant Breeding and Acclimatization, Powstańców Wielkopolskich 10, 85-090 Bydgoszcz,
Poland. 相似文献
7.
Pollen sporopollenin: degradation and structural elucidation 总被引:1,自引:0,他引:1
E. Domínguez José A. Mercado Miguel A. Quesada A. Heredia 《Sexual plant reproduction》1999,12(3):171-178
We report the isolation of purified sporopollenin from pollen grains of different species and its complete solubilization.
Exine from Pinus pinaster, Betula alba, Ambrosia elatior and Capsicum annuum was extracted by treatment with hydrogen fluoride in pyridine. These exines were purified from their aromatic moieties and
from fatty acids linked by ester bonds using acidolysis and saponification treatments. The biopolymer obtained retains almost
completely the shape of the original pollen grain. Fourier-transform infrared spectroscopy analysis of the isolated sporopollenin
showed the absence of polysaccharide and phenolic material and the presence of carboxylic acid groups joined to unsaturations
and ether linkages. Sporopollenin samples were successfully degraded by exhaustive 24-h ozonolysis at room temperature. Gentle
ozonolysis (3 h at 0°C) did not completely degrade the biopolymer. The compounds obtained after exhaustive ozonolysis were
analysed by gas chromatography-mass spectrometry. Dicarboxylic acids with a low number of carbon atoms were identified as
major components of sporopollenin from P. pinaster, A. elatior and C. annuum, representing 28.8%, 63.2% and 88.5%, respectively, of the total compounds obtained. Fatty acids and n-alkanes also were identified in P. pinaster, A. elatior and B. alba sporopollenin. From the data obtained, an hypothesis about the chemical nature and structural arrangement of the sporopollenin
is proposed.
Received: 8 November 1998 / Revision accepted: 14 April 1999 相似文献
8.
The present paper describes the pollen morphology of 27 species, 4 varieties and 1
form of Asarum from China. The pollen grains were all examined under light microscope and
scanning electron microscope. The apertures of pollen grains of Asarum are variable and so
distinct as to allow the identification of individual subgenera and species. The exine
ornamentation is compound and may be divided into two types: reticulate or cerebelloid under verrucae. The pollen grains of Subgen. Asarum and Subgen. Heterotropa are
distinguishable, which supports the taxonomical subdivision based on the gross
morphology. The differences in the pollen morphology between A. caulescens Maxim. and
A. sieboldii Miq. in China and in Japan are discussed and some comparisons in the pollenmorphology between several species similar in the gross morphology are also made. 相似文献
9.
Xi Yi-zhen 《植物学报(英文版)》1988,30(6)
Metasequoia is endemic to China. Present study deals with ultrastructure of pollen exine of M. glyptostroboides Hu et Cheng, and in comparision with other genera of the family. Pollen grains of Metasequoia are spheroidal or subsphoroidal and 27.8(24.3–32.3) μm in diameter. There is a papilla in the distal face. The papilla is wide at the base, 3.5–5.2 μm high, with pointed and circular end and the base crooked toward one side. Exine is about L5 μm thick, layers distinct, Nexine is as thick as sexine. Surface weakly granulate. According to observation by SEM, exine is covered with fine granules and rather coarse tuberculae. The former can be easily separated from the latter. The loose and uneven tuberculae are provided with minute spinules on the surface and generally fall off after acetolysis. The fine and dense granulae, however, remain intact after acetolysis. The study by TEM shows that ektexine is made of granules densely arranged and connected with each other. In addition, sparse Ubisch bodies are unevenly distributed on granular layer with geminate surface. The thick endexine, is composed of 10–15 lamellae. It is worthy to note that all lamellae possess tripartite structure. But lamellae of endexine in other genera of Taxodiaceae have no tripartite structure except the lamella near ektexine. Number of lamella and thickness of endexine in Metasequoia differ from those of other genera in Taxodiaceae; for example endexine with 8–10 lamellae in Taxodium, 8–9 lamellae in Sequoia, 6–7 lamellae in Glyptostrobus, 6–8 lamellae in Cunninghamia, about 16 lamellae in Cryptomeria etc. 相似文献
10.
Eucommia ulmoides Oliver is endemic to China. The pollen morphology and exine
ultrastructure were examined under LM, SEM and TEM. Pollen grains are prolate, polar
axis 30.5-54.8 μm long, with the average 32.7 μm, equatorial axis 27.8-31.3 μm long, with
the average 29.2 μm, tricolporoidate, but sometimes the outline of ora could be observed and
elliptic in shape. Colpi are narrow, uequal in length, often two long and one short or two
short and one long, sometimes rather irregularly arranged, with indistinct and thin colpus
membrance. Exine psilate under LM, granulate under SEM, and shortly baculate under
TEM. Tectum is thin with dense and small granules, columellae layer consists of short bacules, and foot layer very thick.
Some taxonomists (Cronquist, 1968) consider that Eucommiaceae is related to Hamamelidales, but others (Takhtajan, 1969) to Urticales. The Urticales is of the porate type of pollen
grains, while Eucommiaceae of tricolporoidate type, and thus the former is more advanced
than the latter. Pollen grains of some members of Hamamelidales, tricolporoidate, are similar to those of Eucommiaceae. We therefore consider that Eucommiaceae is related to Hama-melidales. 相似文献