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181.
With regard to adaptation of green ash (Fraxinus pennsylvanica
Marshall) to ecological conditions in Croatia, pollen germination and pollen tube length after 2, 4 and 6 hours were examined in vitro at 10, 15, 20 and 25°C during two years 2001 and 2002. Narrow leaved ash (F. angustifolia
Vahl) pollen served as a control in 2002. The year, time and temperature, and the interaction between time and temperature were
significant for both germination percentage and pollen tube length. Interactions year × temperature and year × time were significant
for pollen tube length only. The highest germination percentage (17.86% in 2001 and 19.40% in 2002) of green ash pollen was
at 15°C after 6 hours. The pollen tube length was greatest at 20°C (393.46 μm) in 2001 and 25°C (899.50 μm) in 2002 after
6 hours. Narrow leaved ash pollen had the highest germination percentage (19.22%) at 20°C after 6 hours and was significantly
reduced at 25°C. The pollen tube length was greatest at 25°C (518.90 μm) after 6 hours. It can be concluded that green ash
pollen has satisfactory germination in ecological conditions in Croatia and that the optimum temperature for pollen germination
is higher than 20°C. 相似文献
182.
Performance of marker-based relatedness estimators in natural populations of outbred vertebrates
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Csilléry K Johnson T Beraldi D Clutton-Brock T Coltman D Hansson B Spong G Pemberton JM 《Genetics》2006,173(4):2091-2101
Knowledge of relatedness between pairs of individuals plays an important role in many research areas including evolutionary biology, quantitative genetics, and conservation. Pairwise relatedness estimation methods based on genetic data from highly variable molecular markers are now used extensively as a substitute for pedigrees. Although the sampling variance of the estimators has been intensively studied for the most common simple genetic relationships, such as unrelated, half- and full-sib, or parent-offspring, little attention has been paid to the average performance of the estimators, by which we mean the performance across all pairs of individuals in a sample. Here we apply two measures to quantify the average performance: first, misclassification rates between pairs of genetic relationships and, second, the proportion of variance explained in the pairwise relatedness estimates by the true population relatedness composition (i.e., the frequencies of different relationships in the population). Using simulated data derived from exceptionally good quality marker and pedigree data from five long-term projects of natural populations, we demonstrate that the average performance depends mainly on the population relatedness composition and may be improved by the marker data quality only within the limits of the population relatedness composition. Our five examples of vertebrate breeding systems suggest that due to the remarkably low variance in relatedness across the population, marker-based estimates may often have low power to address research questions of interest. 相似文献
183.
Wang QF Prabhakar S Wang Q Moses AM Chanan S Brown M Eisen MB Cheng JF Rubin EM Boffelli D 《Genome biology》2006,7(8):R68-9
Background
Sequence changes in regulatory regions have often been invoked to explain phenotypic divergence among species, but molecular examples of this have been difficult to obtain. 相似文献184.
A microsatellite-based consensus linkage map for species of Eucalyptus and a novel set of 230 microsatellite markers for the genus 总被引:1,自引:0,他引:1
Rosana PV Brondani Emlyn R Williams Claudio Brondani Dario Grattapaglia 《BMC plant biology》2006,6(1):20-16
Background
Eucalypts are the most widely planted hardwood trees in the world occupying globally more than 18 million hectares as an important source of carbon neutral renewable energy and raw material for pulp, paper and solid wood. Quantitative Trait Loci (QTLs) in Eucalyptus have been localized on pedigree-specific RAPD or AFLP maps seriously limiting the value of such QTL mapping efforts for molecular breeding. The availability of a genus-wide genetic map with transferable microsatellite markers has become a must for the effective advancement of genomic undertakings. This report describes the development of a novel set of 230 EMBRA microsatellites, the construction of the first comprehensive microsatellite-based consensus linkage map for Eucalyptus and the consolidation of existing linkage information for other microsatellites and candidate genes mapped in other species of the genus. 相似文献185.
186.
Pavic D 《Journal of biosocial science》2012,44(3):357-364
This investigation aims to contribute to the existing literature on demographic and ecological factors affecting the sex ratio at birth, by analysing the births in Croatia from 1998 to 2008. Data from birth certificates for all Croatian births for the investigated period (n=420,256) were used to establish the link between parental ages, birth order, region of birth, parental occupation and parental education level, and sex of the child. The χ2 test and t-test were used to assess the significance of each of the factors, along with multiple logistic regression to control for possible confounding effects. The results suggest that a joint higher age of both parents significantly lowers the sex ratio at birth. There is also a regional variation in sex ratio at birth, the lowest value being in Central Croatia and the highest in the City of Zagreb. Changes in the reproductive physiology of older parents are most probably responsible for the lower sex ratio, although the limited sample size warns against widespread generalizations. The causes of the regional variation in sex ratio at birth are most likely the different regional levels of obesity and physical inactivity. 相似文献
187.
188.
Brodehl A Hedde PN Dieding M Fatima A Walhorn V Gayda S Šarić T Klauke B Gummert J Anselmetti D Heilemann M Nienhaus GU Milting H 《The Journal of biological chemistry》2012,287(19):16047-16057
Mutations in the DES gene coding for the intermediate filament protein desmin may cause skeletal and cardiac myopathies, which are frequently characterized by cytoplasmic aggregates of desmin and associated proteins at the cellular level. By atomic force microscopy, we demonstrated filament formation defects of desmin mutants, associated with arrhythmogenic right ventricular cardiomyopathy. To understand the pathogenesis of this disease, it is essential to analyze desmin filament structures under conditions in which both healthy and mutant desmin are expressed at equimolar levels mimicking an in vivo situation. Here, we applied dual color photoactivation localization microscopy using photoactivatable fluorescent proteins genetically fused to desmin and characterized the heterozygous status in living cells lacking endogenous desmin. In addition, we applied fluorescence resonance energy transfer to unravel short distance structural patterns of desmin mutants in filaments. For the first time, we present consistent high resolution data on the structural effects of five heterozygous desmin mutations on filament formation in vitro and in living cells. Our results may contribute to the molecular understanding of the pathological filament formation defects of heterozygous DES mutations in cardiomyopathies. 相似文献
189.
Schiavinato A Becker AK Zanetti M Corallo D Milanetto M Bizzotto D Bressan G Guljelmovic M Paulsson M Wagener R Braghetta P Bonaldo P 《The Journal of biological chemistry》2012,287(14):11498-11515
EMILIN-3 is a glycoprotein of the extracellular matrix belonging to a family that contains a characteristic N-terminal cysteine-rich EMI domain. Currently, EMILIN-3 is the least characterized member of the elastin microfibril interface-located protein (EMILIN)/Multimerin family. Using RNA, immunohistochemical, and protein chemistry approaches, we carried out a detailed characterization of the expression and biochemical properties of EMILIN-3 in mouse. During embryonic and postnatal development, EMILIN-3 showed a peculiar and dynamic pattern of gene expression and protein distribution. EMILIN-3 mRNA was first detected at E8.5-E9.5 in the tail bud and in the primitive gut, and at later stages it became abundant in the developing gonads and osteogenic mesenchyme. Interestingly and in contrast to other EMILIN/Multimerin genes, EMILIN-3 was not found in the cardiovascular system. Despite the absence of the globular C1q domain, immunoprecipitation and Western blot analyses demonstrated that EMILIN-3 forms disulfide-bonded homotrimers and higher order oligomers. Circular dichroism spectroscopy indicated that the most C-terminal part of EMILIN-3 has a substantial α-helical content and forms coiled coil structures involved in EMILIN-3 homo-oligomerization. Transfection experiments with recombinant constructs showed that the EMI domain contributes to the higher order self-assembly but was dispensable for homotrimer formation. EMILIN-3 was found to bind heparin with high affinity, a property mediated by the EMI domain, thus revealing a new function for this domain that may contribute to the interaction of EMILIN-3 with other extracellular matrix and/or cell surface molecules. Finally, in vitro experiments showed that EMILIN-3 is able to function as an extracellular regulator of the activity of TGF-β ligands. 相似文献