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1.
Alessandra Moscatelli Giampiero Cai Guo-Qin Liu Antonio Tiezzi Mauro Cresti 《Sexual plant reproduction》1996,9(6):312-317
Microtubules in pollen tubes are evident within the vegetative and generative cell cytoplasm. This observation led to the
formulation of several hypotheses regarding the role of microtubules in cytoplasmic movement and the migration of the vegetative
nucleus/generative cell along the pollen tube. The study of microtubular motor proteins in pollen tubes followed the discovery
and characterization of an immunoreactive homolog of mammalian kinesin in tobacco pollen tubes. Recent identification of dynein-related
polypeptides in pollen tubes of Nicotiana tabacum and pollen of Ginkgo biloba is a significant step in the definition of the role of microtubule function within pollen and pollen tubes.
Received: 31 May 1996 / Revision accepted: 26 July 1996 相似文献
2.
采用丙酮粉抽提,DEAE-SephadexA-50、SephacrylS-300、MonoQ柱层析,从银杏(GinkgobilobaL.)花粉中分高纯化出微管蛋白(tubulin),其两个亚基(α、β)的分子量分别为54kD和52kD.纯化的微管蛋白可与鸡脑微管蛋白抗体发生免疫交叉反应. 相似文献
3.
银杏种仁中抗菌蛋白的纯化及性质 总被引:18,自引:2,他引:16
银杏果仁提取上清液经硫酸铵沉淀、CM—52离子交换柱层析和Sephadex G-50凝胶过滤层析后分离纯化出一种抗菌蛋白。SDS—PAGE分析结果表明,此蛋白分子量为13000,对热稳定;氨基酸组分分析表明,该蛋白含18种不同氨基酸,尤富含丙氨酸(Ala)和精氨酸(His)等,缺乏半胱氨酸(Cys);纯化的蛋白对黄瓜镰刀孢菌(Fusarium oxysporum)、瓜类炭疽菌(Colletotrichum orbiculare)、小麦全蚀病菌(Gaeumannomyces graminis)等真菌有很强的抑制作用,而且对金黄色葡萄球菌(Staphylococcus aureus)、大肠杆菌(Escherichia Coli)等细菌也有一定的抑制作用。 相似文献
4.
We examined the influence of pollen competitive environment on pollen performance in Mirabilis
jalapa. We used the number of pollen grains and the number of pollen tubes per pistil as measures of pollen competition. Pollen
germination, pollen tube penetration into the style, and pollen tube growth rates were used as measures of pollen performance.
All three measures of pollen performance were affected by the competitive environment. Pollen germination was greatest at
intermediate pollen load sizes. The percentage of germinated pollen grains that penetrated the stigma and grew into the style
decreased with pollen load size. Pollen tube growth rate in the style was greater and more variable with larger numbers of
pollen tubes in the style. Controlling for the degree of selection at the stigma indicated that pollen-pollen or pollen-style
interactions were the likely causes of increased growth rates.
Received: 28 October 1996 / Revision accepted: 24 January 1997 相似文献
5.
Anuradha Chaudhuri 《Journal of biosciences》1986,10(3):323-333
Tubulin was purified from the brain of the catfishHeteropneustes fossilis by cycles of temperature-dependent assembly and disassembly. Fish tubulin assembles into microtubules in the absence of high
molecular weight microtubule associated proteins. Its subunits comigrate with goat brain α andβ tubulin subunits and is composed of 4 major α andβ tubulins each as analyzed by isoelectric focusing and two dimensional gel electrophoresis. Peptide mapping showed it to be
very similar to goat brain tubulin. Polymerization of catfish brain tubulin occurs optimally between 18–37°C and the critical
protein concentrations of assembly at 18°C and 37°C are the same, as opposed to mammalian brain tubulins. 相似文献
6.
Effect of pollen competition and stigmatic receptivity on seed set in white clover (Trifolium repens L.) 总被引:1,自引:0,他引:1
The effect of competition between incompatible and compatible pollen grains on the seed production of white clover was studied.
Stigmatic receptivity was also studied. A selection line of white clover that has red leaves was used as a pollen donor and
as a genetic marker to allow determination of the pollen donor responsible for ovule fertilisation. Results show that incompatible
pollen did not inhibit compatible pollen grains from fertilising ovules and producing seeds, although it did slightly impair
seed yield. At temperatures of 20/10°C (day/night) stigmas of white clover remained receptive to additional pollination up
to 32 h after an initial compatible pollination and 40 h after an incompatible pollination. The results imply that factors
other than inadequate pollination and the self-incompatibility system are responsible for failure of white clover to attain
its potential seed yield.
Received: 31 August 1999 / Revision accepted: 28 February 2000 相似文献
7.
A new procedure to asses pollen viability 总被引:4,自引:0,他引:4
We tested pollen viability of eight species using four vital dyes, a new peroxidase test together with three other established
methods (MTT, Baker’s and X-Gal), to determine their potential to differentiate fresh pollen from pollen heated for 2 h and
24 h at 80°C (killed pollen) and compared the results with in vitro germination. We found that two of three dyes previously
employed to determine viability also stained killed pollen, while the new peroxidase test and MTT did not. We suggest that
the latter two are the best methods to test pollen viability, since they do not normally stain either killed or aborted pollen.
Received: 7 May 1999 / Revision accepted: 25 October 1999 相似文献
8.
Proteins from pollen of parent forms and amphiploids Aegilops
variabilis ×Secale cereale and Ae. kotschyi×S. cereale, obtained by in vitro propagation or colchicine treatment of F1 hybrids, were subjected to a study by two-dimensional (2-D) electrophoresis. Qualitative and quantitative diversities of
protein patterns were revealed for the amphiploid pollen. The majority of peptides found in the parent forms were also present
in the patterns of the amphiploid pollen; however, some of the parent-form-peptides were not expressed and proteins characteristic
only of the amphiploids appeared. In the 2-D combined protein pattern obtained for the parent forms, amphiploids Ae. variabilis × S. cereale produced pollen with a poorer spectrum of proteins. In amphiploid 408B, obtained from treated the F1 generation with colchicine, the 2-D pattern revealed the presence of less than 50% of the proteins recorded for the parent
forms. Pollen grain morphology was studied under a scanning microscope. The structure and shape of exines differed from those
of the parents. In the parent forms the pollen grains had only one pore, while in amphiploid pollen, one, two or three pores
were observed. Possible explanations for the differences in the 2-D patterns of amphiploids and their parent forms (impoverishment
of the protein spectrum and appearance of new peptides) are (1) somaclonal variation and mutagenic activity of colchicine,
(2) suppression of structural genes, (3) activity of regulators and (4) translocations. Pollen grains with two or even three
pores could appear as a result of the independent activity of the genes from three amphiploidal genomes.
Received: 6 March 2001 / Accepted: 26 June 2001 相似文献
9.
The four-celled mature pollen of Ginkgo biloba L. just shed from the microsporangia,
was round in shape and contained a very large germination area with monosulcate sulcus walled with
two semicircular and nearly perpendicular parts of exine, and the pollen was coated with a compact
irregular striations and spinules in parts other than the germination area. The pollen became boatshaped and was bilaterally symmetrical when it was in air or under cold storage, but rapidly rounded
off in cultural solution. Studies on early morphogenesis of the male gametophyte in vitro and in vivo
revealed that the tube nucleus turned a certain degree of angle, and was followed by lateral germination, while the non-active pollen maintained its round shape. The results suggest that the internal
feature of the pollen tube could be a determinant factor contributing to the expression of the characteristic events of lateral germination of the male gametophyte in G. biloba. Furthermore, this biologically consistent character, together with the characteristic pollen morphology, is quite different from
those of other groups in gymnosperms such as Cycas and Pinus. This might be a critical characterrelevant to the systematic position of G. biloba. 相似文献
10.
Cytological details of endosperm development after pollination with irradiated pollen were studied in Actinidia deliciosa (kiwifruit) cultivar Hayward. Pollinations were carried out involving five different sources of pollen (Matua, Tomuri, Burt,
Berryman, and fruiting male) irradiated with gamma rays at doses of 700 and 900 Gy. Non-irradiated crosses were used as controls.
Irradiated pollen induced development of approximately 25–30% of the ovules. Two types of ovules were observed: (1) with both
embryo and endosperm and (2) with endosperm only. No mitotic abnormalities were found in control or irradiated endosperms.
Mitotic divisions were regular and nuclei spherical and evenly spaced. However, the cells of irradiated endosperm usually
contained low amounts of storage products. Ploidy level of the endosperms was evaluated by nuclear size (volume) with the
use of image analyzis. Mean nuclear size in control and irradiated endosperms was 1598.3 and 750.9 μm3, respectively. It is concluded that endosperm produced after pollination with irradiated pollen is autonomous and represents
the 2n level.
Received: 14 October 1998 / Revision accepted: 10 March 1999 相似文献
11.
银杏外种皮的双黄酮成分 总被引:9,自引:0,他引:9
从银杏外种皮的乙酸乙酯提取中分离得到6个化合物,其中5个经物理常数及光谱分析鉴定为金松双黄酮、银杏素、奶杏素、1-5’-甲氧基白果素及白果素。这些化合物均首次从银杏外种皮分离。 相似文献
12.
13.
MAP kinase signaling during pollen development 总被引:1,自引:0,他引:1
E. Heberle-Bors Viktor Voronin Alisher Touraev Pilar Sanchez Testillano Maria Carmen Risueño Cathal Wilson 《Sexual plant reproduction》2001,14(1-2):15-19
The stereotypical events of pollen grain maturation and its coordinated development with other flower tissues requires the
interplay of different signalling pathways in order to ensure efficient fertilisation and, eventually, seed set. In recent
years evidence has accumulated that members of the mitogen-activated protein kinase (MAP kinase) family are expressed in pollen
and may function as regulators of both pollen development and germination. In this review we describe what is known about
MAP kinases in pollen and discuss their possible function(s) in pollen biology.
Received: 14 December 2000 / Accepted: 6 June 2001 相似文献
14.
银杏叶中聚戊烯醇含量及其季节性变化 总被引:4,自引:0,他引:4
银杏 (GinkgobilobaL .)叶中聚戊烯醇 (polyprenols)含量较高[1] ,聚戊烯醇在人体中是多萜醇的中间体[2 ] ,对细胞膜糖蛋白生物合成具有重要作用[3 ] ,用于多发性硬化症 (痛风 ,红斑狼疮等 )等免疫功能疾病、糖尿病、慢性肝炎及肿瘤病人化疗的辅助治疗 相似文献
15.
G. Giddings 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(6):971-974
The dispersal of pollen from a Lolium perenne source has previously been described using various Gaussian plume models which take distance and wind direction into account.
One of these models is used here to calculate, using integration, possible pollen deposition onto small conspecific populations
a kilometer from the source. The percentage of immigrant pollen is compared for six different sets of parameter values previously
estimated from pollen-dispersal experiments. The source size is then scaled up to simulate what might happen if transgenic
ryegrass was grown on a large scale. In this case it is seen that small conspecific populations might, in some conditions,
be swamped by immigrant pollen, even if they are not directly downwind of the source. The implications of this are discussed
in terms of assessing and managing the risks of releasing wind-pollinated transgenic crops.
Received: 10 July 1999 / Accepted: 27 August 1999 相似文献
16.
Differential localization of the LIM domain protein PLIM-1 in microspores and mature pollen grains from sunflower 总被引:3,自引:0,他引:3
Rachel Baltz Anne-Catherine Schmit Marianne Kohnen François Hentges André Steinmetz 《Sexual plant reproduction》1999,12(1):60-65
PLIM-1 is a LIM domain protein specifically expressed in pollen grains. Using two PLIM-1-specific monoclonal antibodies we
studied its expression and intracellular location at various developmental stages of sunflower (Helianthus annuus L.) pollen. Our studies show that the protein appears at the microspore stage in a limited number of cytoplasmic bodies,
becomes undetectable in bicellular pollen, and reappears in tricellular pollen grains in cortical patches particularly concentrated
in the F-actin-enriched germination cones of the vegetative cell. The developmental stage-dependent, different location of
the protein suggests a dual function during pollen development. While this function in microspore development remains obscure,
the high concentration of PLIM-1 in the germination cones of mature pollen suggests that it participates in the germination
process as well as in pollen tube growth.
Received: 11 August 1998 / Revision accepted: 15 December 1998 相似文献
17.
ZM13 is a pollen-specific maize gene which is expressed in the late stages of pollen development. We wished to utilize the ZM13 promoter to examine the expression of a synthetic green fluorescent protein (SGFP) in germinating pollen. The usefulness
of the SGFP expression product is that its appearance and distribution can be monitored non-destructively in vivo. A plasmid
containing the SGFP coding region under the control of the ZM13 promoter was constructed and then transiently transformed into pollen of Tradescantia paludosa and Nicotiana tabacum by the use of microprojectile bombardment. The expression of the green fluorescent protein was analyzed by fluorescence microscopy
using a fluorescein filter. Expression began about 3 h post-bombardment, and all parts of the pollen grain and tube fluoresced.
High levels of fluorescence were observed for several days following treatment.
Received: 15 February 1998 / Revision accepted: 22 April 1998 相似文献
18.
Catharanthus roseus cell suspension cultures converted exogenously added curcumin to a series of curcumin glucosides that possessed drastically enhanced water solubility. A cDNA clone encoding a glucosyltransferase responsible for glucosylation of curcumin to form curcumin 4'-O-glucoside was previously isolated, and in the present study a novel sugar-sugar glycosyltransferase, UDP-glucose:curcumin glucoside glucosyltransferase (UCGGT), was purified approximately 900-fold to apparent homogeneity from cultured cells of C. roseus. The purified enzyme (0.2% activity yield) catalyzed 1,6-glucosylation of curcumin 4'-O-glucoside to yield curcumin 4'-O-gentiobioside. The molecular weight and isoelectric point were estimated to be about 50 kDa and 5.2, respectively. The enzyme showed a pH optimum between 7.5 and 7.8. Both flavonoid 3-O- and 7-O-glucosides were also preferred acceptor substrates of the enzyme, whereas little activity was shown toward simple phenolic glucosides such as arbutin and glucovanillin, cyanogenic glucoside (prunasin) or flavonoid galactoside. These results suggest that UCGGT may also function in the biosynthesis of flavonoid glycosides in planta. 相似文献
19.
Silva Palacios I Tormo Molina R Nuñoz Rodríguez AF 《International journal of biometeorology》2000,44(3):128-133
The daily pollen concentration in the atmosphere of Badajoz (SW Spain) was analysed over a 6-year period (1993–1998) using
a volumetric aerobiological trap. The results for the main pollination period are compared with the number of hours of wind
each day in the four quadrants: 1 (NE), 2 (SE), 3 (SW) and 4 (NW). The pollen source distribution allowed 16 pollen types
to be analysed as a function of their distribution in the four quadrants with respect to the location of the trap. Four of
them correspond to species growing in an irrigated farmland environment (Amaranthaceae-Chenopodiaceae, Plantago, Scirpus, and Typha), five to riparian and woodland species (Salix, Fraxinus, Alnus, Populus, and Eucalyptus), four to urban ornamentals (Ulmus, Arecaceae, Cupressaceae, and Casuarina), and three which include the most frequent pollen grains of widely distributed species (Poaceae, Quercus, and Olea). The results show that the distribution of the sources and the wind direction play a very major role in determining the
pollen concentration in the atmosphere when these sources are located in certain quadrants, and that the widely distributed
pollen sources show no relationship with wind direction. In some years the values of the correlations were not maintained,
which leads one to presume that, in order to draw significant conclusions and establish clear patterns of the influence of
wind direction, a continuous and more prolonged study will be required.
Received: 6 May 1999 / Revised: 30 March 2000 / Accepted: 31 March 2000 相似文献
20.
Occurrence of mono- or disaccharides and polysaccharide reserves in mature pollen grains 总被引:1,自引:0,他引:1
Pollen from 13 species of gymnosperms and angiosperms was studied for soluble and insoluble carbohydrates at dispersal. Starch
reserves stored during pollen development give rise to carbohydrates at maturity. Combinations of different types of carbohydrates
in mature pollen may depend on the extent of starch hydrolysis. An inverse relationship was found between the extent of starch
hydrolysis and sucrose content. If the starch was scarcely de-polymerized, the cytoplasm had very low levels of soluble sugars
and none of the periodic acid-Schiff (PAS)-positive material as found in pollen not subject to high dehydration (Cucurbita pepo L., Zea mays L.). After total or partial starch hydrolysis, insoluble PAS-positive oligo/polysaccharides were found in the cytoplasm associated
with much soluble sugar, and the pollen grains were dehydrated at dispersal as in Typha latifolia L., Chamaerops humilis L., Trachycarpus excelsa Wendl., and other specimens. Intermediate levels of starch and soluble sugars, together with cytoplasmic PAS-positive material,
characterized species with dehydrated pollen such as Pinus halepensis Miller. Carbohydrates may be related to pollen longevity, which largely depends on the abundance of sucrose, which is known
to protect membrane integrity. The relationship between PAS-positive material and pollen viability is unclear at present.
Received: 30 July 1996 / Revision accepted: 18 December 1996 相似文献