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51.
Programmed cell death during development of cowpea (Vigna unguiculata (L.) Walp.) seed coat 下载免费PDF全文
NATHÁLIA BASTOS LIMA FERNANDA GOMES TRINDADE MAURA DA CUNHA ANTÔNIA ELENIR AMÂNCIO OLIVEIRA JENNIFER TOPPING KEITH LINDSEY KÁTIA VALEVSKI SALES FERNANDES 《Plant, cell & environment》2015,38(4):718-728
The seed coat develops primarily from maternal tissues and comprises multiple cell layers at maturity, providing a metabolically dynamic interface between the developing embryo and the environment during embryogenesis, dormancy and germination of seeds. Seed coat development involves dramatic cellular changes, and the aim of this research was to investigate the role of programmed cell death (PCD) events during the development of seed coats of cowpea [Vigna unguiculata (L.) Walp.]. We demonstrate that cells of the developing cowpea seed coats undergo a programme of autolytic cell death, detected as cellular morphological changes in nuclei, mitochondria, chloroplasts and vacuoles, DNA fragmentation and oligonucleosome accumulation in the cytoplasm, and loss of membrane viability. We show for the first time that classes 6 and 8 caspase‐like enzymes are active during seed coat development, and that these activities may be compartmentalized by translocation between vacuoles and cytoplasm during PCD events. 相似文献
52.
Assessing population density is crucial for studying the ecology and evolutionary biology of species as well as for conservation purposes. Here we used point count methods to infer population density in a single-island endemic passerine bird, the Réunion Grey White-eye Zosterops borbonicus, that displays striking evidence of differentiation at a small spatial scale. Population density was estimated at 5.17 birds ha?1 (CL 4.85–5.50), a value somewhat higher than previously believed. This estimation provides the first detailed estimation of bird population density in the vulnerable summit ecosystems of Réunion and will possibly allow a better understanding of the evolutionary causes of this plumage colour variation. 相似文献
53.
In a simulation study different designs for a pure line pig population were compared for efficiency of mapping QTL using the variance component method. Phenotypes affected by a Mendelian QTL, a paternally expressed QTL, a maternally expressed QTL or by a QTL without an effect were simulated. In all alternative designs 960 progeny were phenotyped. Given the limited number of animals there is an optimum between the number of families and the family size. Estimation of Mendelian and parentally expressed QTL is more efficient in a design with large family sizes. Too small a number of sires should be avoided to minimize chances of sires to be non-segregating. When a large number of families is used, the number of haplotypes increases which reduces the accuracy of estimating the QTL effect and thereby reduces the power to show a significant QTL and to correctly position the QTL. Dense maps allow for smaller family size due to exploitation of LD-information. Given the different possible modes of inheritance of the QTL using 8 to16 boars, two litters per dam was optimal with respect to determining significance and correct location of the QTL for a data set consisting of 960 progeny. The variance component method combining linkage disequilibrium and linkage analysis seems to be an appropriate choice to analyze data sets which vary in marker density and which contain complex family structures. 相似文献
54.
55.
Martinus AM van Boekel Erik R Vossenaar Frank HJ van den Hoogen Walther J van Venrooij 《Arthritis research & therapy》2001,4(2):87
The diagnosis of rheumatoid arthritis (RA) is primarily based on clinical symptoms, so it is often difficult to diagnose RA in very early stages of the disease. A disease-specific autoantibody that could be used as a serological marker would therefore be very useful. Most autoimmune diseases are characterized by a polyclonal B-cell response targeting multiple autoantigens. These immune responses are often not specific for a single disease. In this review, the most important autoantibody/autoantigen systems associated with RA are described and their utility as a diagnostic and prognostic tool, including their specificity, sensitivity and practical application, is discussed. We conclude that, at present, the antibody response directed to citrullinated antigens has the most valuable diagnostic and prognostic potential for RA. 相似文献
56.
Hendrik-Jan Megens Richard PMA Crooijmans Magali San Cristobal Xiao Hui Ning Li Martien AM Groenen 《遗传、选种与进化》2008,40(1):103-128
Microsatellite diversity in European and Chinese pigs was assessed using a pooled sampling method on 52 European and 46 Chinese pig populations. A Neighbor Joining analysis on genetic distances revealed that European breeds were grouped together and showed little evidence for geographic structure, although a southern European and English group could tentatively be assigned. Populations from international breeds formed breed specific clusters. The Chinese breeds formed a second major group, with the Sino-European synthetic Tia Meslan in-between the two large clusters. Within Chinese breeds, in contrast to the European pigs, a large degree of geographic structure was noted, in line with previous classification schemes for Chinese pigs that were based on morphology and geography. The Northern Chinese breeds were most similar to the European breeds. Although some overlap exists, Chinese breeds showed a higher average degree of heterozygosity and genetic distance compared to European ones. Between breed diversity was even more pronounced and was the highest in the Central Chinese pigs, reflecting the geographically central position in China. Comparing correlations between genetic distance and heterozygosity revealed that China and Europe represent different domestication or breed formation processes. A likely cause is a more diverse wild boar population in Asia, but various other possible contributing factors are discussed. 相似文献
57.
Catimel B; Scott AM; Lee FT; Hanai N; Ritter G; Welt S; Old LJ; Burgess AW; Nice EC 《Glycobiology》1998,8(9):927-938
We describe a novel immobilization technique to investigate interactions
between immobilized gangliosides (GD3, GM1, and GM2) and their respective
antibodies, antibody fragments, or binding partners using an optical
biosensor. Immobilization was performed by direct injection onto a
carboxymethyldextran sensor chip and did not require derivatization of the
sensor surface or the ganglioside. The ganglioside appeared to bind to the
sensor surface by hydrophobic interaction, leaving the carbohydrate epitope
available for antibody or, in the case of GM1, cholera toxin binding. The
carboxyl group of the dextran chains on the sensor surface did not appear
to be involved in the immobilization as evidenced by equivalent levels of
immobilization following conversion of the carboxyl groups into acyl amino
esters, but rather the dextran layer provided a hydrophilic coverage of the
sensor chip which was essential to prevent nonspecific binding. This
technique gave better reactivity and specificity for anti- ganglioside
monoclonal antibodies (anti-GD3: KM871, KM641, R24; and anti-GM2: KM966)
than immobilization by hydrophobic interaction onto a gold sensor surface
or photoactivated cross-linking onto carboxymethydextran. This rapid
immobilization procedure has facilitated detailed kinetic analysis of
ganglioside/antibody interactions, with the surface remaining viable for a
large number of cycles (>125). Kinetic constants were determined from
the biosensor data using linear regression, nonlinear least squares and
equilibrium analysis. The values of kd, ka, and KAobtained by nonlinear
analysis (KAKM871 = 1.05, KM641 = 1.66, R24 = 0.14, and KM966 = 0.65 x
10(7) M- 1) were essentially independent of concentration and showed good
agreement with data obtained by other analytical methods.
相似文献
58.
Marsupials and monotremes sort genome treasures from junk 总被引:1,自引:0,他引:1
A recent landmark paper demonstrates the unique contribution of marsupials and monotremes to comparative genome analysis, filling an evolutionary gap between the eutherian mammals (including humans) and more distant vertebrate species. 相似文献
59.
Arianna Tavanti Lambert AM Hensgens Selene Mogavero László Majoros Sonia Senesi Mario Campa 《BMC microbiology》2010,10(1):203